#Bundibugyo Virus Disease #Outbreak, #DRC, #Uganda - Situation #Report 16, Data as of 30 August 2026 (WHO, summary): 6,100 cases & 2,950 deaths in DRC

 

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Event description

Democratic Republic of the Congo

    The Bundibugyo virus disease (BVD) outbreak in the Democratic Republic of  the Congo continues to evolve, characterized by sustained transmission, high mortality and continued geographic expansion. 

    The epidemiological picture is increasingly heterogeneous, with  persistent transmission in established hotspots in Ituri, intensifying transmission  in parts of Nord-Kivu and Haut-Uélé, and the continued emergence of cases in  previously unaffected health zones. 

    Since External Situation Report #15, a further 516 confirmed cases and 270 confirmed deaths have been reported, bringing the cumulative total to 6100 confirmed cases, including 2950 deaths (CFR 48.4%), as of 30 August 2026. 

    The number of affected health zones has increased from 57 to 60 across  six provinces, with Biena and Manguredjipa in Nord-Kivu and Ganga in  Bas-Uélé newly affected since the previous update. 

    Ituri remains the epicentre, accounting for 82.2% of cumulative confirmed  cases, although continued expansion in Nord-Kivu and Bas-Uélé underscores the  increasingly dispersed geographic pattern of the outbreak.

    During the most recent 21 days (10 – 30 August 2026), 1719 confirmed cases were reported nationally. Compared with 1958 cases during the preceding 21-day period (20 July – 9 August 2026), this represents a decrease of 239 cases (−12.2%). This decline should be interpreted cautiously given  potential reporting delays and retrospective data reconciliation and does not, on its own, establish that transmission is declining. 

    The national trend continues to mask substantial geographic heterogeneity.  

    Reported cases declined by 21.6% in Ituri, from 1601 to 1255, but  increased by 33.2% in Nord-Kivu, from 256 to 341, and by 12.4% in Haut- Uelé, from 97 to 109. Consequently, Ituri’s contribution to newly reported cases  fell from 81.8% to 73.0%, while Nord-Kivu’s contribution increased from 13.1% to 19.8% and HautUélé’s from 5.0% to 6.3%. 

    A further 10 cases were reported in Tshopo and four in the newly affected  Bas-Uélé during the latest period. 

    The latest provincial cumulative totals confirm that Ituri remains the  principal focus, but transmission is becoming progressively less concentrated in  the original epicentre.

    During the same period, 939 confirmed deaths were reported nationally,  compared with 1044 deaths during the preceding 21 days, representing a  decrease of 105 deaths (−10.1%). This decline was again driven predominantly  by Ituri, where reported deaths decreased from 809 to 654 (−19.2%). 

    In contrast, deaths increased from 197 to 228 (+15.7%) in Nord-Kivu and  from 37 to 50 (+35.1%) in Haut-Uélé. Consequently, Ituri’s contribution to newly  reported deaths declined from 77.5% to 69.6%, while Nord-Kivu’s increased from  18.9% to 24.3% and Haut-Uélé’s from 3.5% to 5.3%. Tshopo reported four  deaths and Bas-Uélé three during the latest period. Taken together, the decline in  both reported cases and deaths suggests a reduction in the nationally reported  disease burden. However, reporting delays and retrospective data reconciliation  limit interpretation, while simultaneous increases in cases and deaths in Nord-Kivu and Haut-Uélé demonstrate that transmission remains substantial and is  continuing to redistribute geographically.

Figure 1. Daily trend in confirmed Bundibugyo virus disease cases, with seven-day moving average, by date of report, Democratic Republic of the Congo, as of 30 August 2026

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    At health-zone level, the national decline masks substantial  heterogeneity across established and emerging transmission foci. Of the 60  health zones affected since the start of the outbreak, comparison of the two  consecutive 21-day periods shows that reported cases increased in 20 health  zones and decreased in 22. 

    

    A further 10 previously affected health zones reported no confirmed  cases during the latest 21 days (Adja, Kambala, Logo and Mahagi in Ituri; Goma  and Lubero in Nord-Kivu; Rungu in Haut-Uélé; Lubunga and Wanie-Rukula in  Tshopo; and Miti-Murhesa in Sud-Kivu), while incidence was unchanged in one health zone (Bafwasende, Tshopo). 

    Seven health zones were newly affected during the latest 21-day period. 

    In Ituri, the reduction was driven particularly by Mongbwalu, where  reported cases declined from 183 to 44 (−139; −76.0%), and Nizi, from 277 to  182 (−95; −34.3%). 

    Cases also declined in Lita, from 84 to 61 (−23; −27.4%), and Rwampara,  from 242 to 191 (−51; −21.1%). 

    Bunia, however, remained the largest active focus and increased from  363 to 383 (+20; +5.5%). Other Ituri health zones also recorded increases,  notably Mangala, from 53 to 126 (+73; +137.7%), Nia-Nia, from 61 to 80 (+19;  +31.1%), and Bambu, from 31 to 66 (+35; +112.9%). 

    Outside Ituri, transmission  continued to intensify in Nord-Kivu,  particularly in Katwa, where cases increased from 112 to 165 (+53;  +47.3%), and Beni, from 30 to 66 (+36; +120.0%). In Haut-Uélé, Isiro increased  from 18 to 51 (+33; +183.3%) and Wamba from 8 to 48 (+40; +500.0%). 

    These patterns show that the overall decline in Ituri is being driven by  substantial reductions in several established hotspots rather than a uniform  decrease across the province; Bunia remains highly active, while other foci within  Ituri and in Nord-Kivu and Haut-Uélé continue to expand. 

    Reported deaths show a similar geographic redistribution but with  important differences from the case trends. In Ituri, deaths declined substantially  in several established hotspots, including Mongbwalu, Nizi, Lita and Rwampara,  consistent with the reduction in reported cases in these areas. However, mortality  remained substantial in Bunia, while increases in cases in Mangala, Nia-Nia and  Bambu indicate continued transmission within the province despite the overall  decline.

    In Nord-Kivu, increasing mortality accompanied the continued growth  of the Katwa and Beni foci, while in Haut-Uélé the increase in deaths was  concentrated particularly in Isiro and Wamba. 

    Overall, the health-zone  pattern reinforces the provincial analysis:  transmission is declining in several formerly dominant Ituri hotspots but is not  declining uniformly. 

    Interpretation of health-zone mortality trends in Ituri should however  remain cautious, particularly because cumulative death counts have undergone  continuing reconciliation and redistribution across health zones, with 329 confirmed deaths in Ituri awaiting allocation to health zone as of 30 August  2026. 

    Mortality remains high, with 270 confirmed deaths reported during the  last seven days, including 171 (63.3%) in the community and 99 (36.7%) in BVD  treatment facilities. 

    The persistently high proportion of community deaths (defined  as both  deaths at home and at non-BVD health facilities) highlights continued challenges  with early detection, referral and timely access to treatment, while mortality in  BVD treatment facilities may reflect late presentation, quality of care and patient  vulnerabilities, including age, malnutrition and comorbidities; further analysis to  understand the risk factors is underway.

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Uganda and France

    Both Uganda and France have not reported new cases for more than 42  days. The outbreak in these countries is considered over by WHO’s norm of 42  days without any cases. 

Risk Assessment

    According to WHO’s latest Rapid Risk Assessment as of 20 August 2026, the risk of further spread remains very high within the Democratic  Republic of the Congo and high for neighbouring countries sharing land  borders with the country. 

    The assessment reflects sustained transmission, continued geographic  expansion, high mortality, population mobility, insecurity and persistent response  challenges. The risk is considered low elsewhere in Africa and globally. 

    The second IHR Emergency Committee, convened on 18 August 2026, also  reviewed the evolving situation and emphasized that the outbreak remains far  from controlled, and continues to constitute a Public Health Emergency of International Concern.

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Situation interpretation

    The overall decline in reported cases and deaths is encouraging but  does not yet indicate that the outbreak is under control. Transmission is becoming  increasingly heterogeneous, with reductions in several established  hotspots in Ituri occurring alongside expanding transmission in Nord-Kivu and  Haut-Uélé and continued emergence of new affected health zones. 

    Persistently high mortality, particularly community deaths, together with  gaps in contact follow-up, referral and treatment capacity, infection  prevention and control, and community acceptance, continue to create opportunities for transmission. 

    The response should therefore become more anticipatory and  geographically targeted, rapidly shifting surveillance, contact tracing, clinical care,  IPC, community engagement, workforce and logistical capacity towards emerging and intensifying hotspots, while sustaining interventions in areas where transmission is declining to prevent resurgence.

Source: 

Link: https://iris.who.int/bitstreams/22a50ebd-a676-4a82-a40e-7feae57dc1fe/download

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Characteristics and Monitoring of the 2026 #Outbreak of #Ebola Disease Caused by #Bundibugyo Virus — #DRC, August 2026 (MMWR, edited)

 

Summary

    ° What is already known about this topic?

        § In May 2026, an outbreak of Ebola disease caused by Bundibugyo virus was identified in the Democratic Republic of the Congo.

    ° What is added by this report?

        § This ongoing outbreak is now the second largest Ebola outbreak in history. The targets for five critical public health response indicators (case detection alerts, contact tracing, laboratory testing, isolation of infected persons, and safe and dignified burials) have not yet been met, and the outbreak continues to expand rapidly.

    ° What are the implications for public health practice?

        § Substantial improvements in established outbreak control measures are crucial to rapidly detect and diagnose cases and isolate and provide treatment for infected persons, prevent funeral-associated transmission to prevent additional spread, and control this rapidly expanding outbreak.

    The Democratic Republic of the Congo (DRC) Ministry of Public Health declared an Ebola outbreak on May 15, 2026. Two days later, CDC activated its Emergency Operations Center as part of the U.S. government response to this rapidly growing outbreak. This report describes the epidemiologic characteristics and monitoring of the ongoing outbreak in DRC.

Investigation and Outcomes

Background

    The 2026 Ebola DRC outbreak caused by Bundibugyo virus is now the second largest Ebola outbreak ever recorded. As of August 21, 2026, DRC reported 5,458 confirmed cases and 2,606 (48%) confirmed deaths. 

    Compared with previous Ebola outbreaks, the increase in cases in DRC is unprecedented, with approximately 5,000 cases in 100 days (Ebola Outbreak: Current Situation | CDC). 

    Cases have been reported from six of the 26 DRC provinces (Bas-Uélé, Haut-Uélé, Ituri, North Kivu, South Kivu, and Tshop), affecting 57 of 151 health zones in the affected provinces. 

    Ituri province remains the outbreak epicenter, accounting for 84% of reported cases. 

    Strategies known to control Ebola outbreaks include community-based surveillance, case detection alert notifications,* rapid and in-depth case investigations, identification and monitoring of contacts, infection control measures (e.g., prompt isolation of persons with suspected or confirmed Bundibugyo virus disease [BVD]), rapid diagnostic testing, mortality surveillance, and safe and dignified burials (SDBs).†

Data Source

    Operational indicators for five domains have been generated based on experience with previous Ebola outbreaks, including DRC’s 2018 outbreak. Targets reflect the levels necessary to end the outbreak. 

    The DRC Ministry of Public Health prepares publicly available daily situation reports, and CDC abstracts data from these reports to evaluate the established indicators each day. Indicator data are monitored over time to assess the outbreak trajectory. This activity was reviewed by CDC, deemed not research, and conducted consistent with applicable federal law and CDC policy.§

Operational Indicator Analysis

    Nearly all operational indicators remain below identified targets (...). 

    Operational indicator values were calculated for the 21-day period of July 31–August 21. 

    The average percentage of alerts investigated within 24 hours (last reported August 5, 2026) was 83% (target = >90%). 

    An average of 10.6 contacts were identified per confirmed case (target = ≥20), suggesting underreporting and underascertainment of case contacts. 

    The percentage of confirmed new cases previously identified as known contacts (last reported July 12, 2026) was 15%–20% (target = >90%); this suggests that most cases are occurring outside known transmission chains. 

    In addition, more than one half (59%) of confirmed Ebola deaths are occurring outside an Ebola treatment unit (ETU) (target = 0%), suggesting insufficient ETU capacity, fear of ETUs, and ongoing spread through unidentified transmission chains. 

    Laboratory testing was performed for 72% of validated alerts (target = >90%), indicating that a substantial number of suspected cases remain untested. 

    Test positivity was 24%, with a target of 0%. 

    Although the national ETU bed occupancy was 64%, meeting the target of <80%, occupancy varied substantially by health zone, with some facilities unable to isolate all infected persons and reporting occupancies as high as 140%. 

    Fewer than one half (49%) of affected health zones had at least one SDB team (target = 100%). 

    Current data were not available for several response indicators, such as percentage of persons with confirmed BVD receiving prompt isolation (target = >90%) and percentage of deaths with SDBs (target = 100%), underscoring ongoing data gaps in this complex public health response.

Preliminary Conclusions and Actions

    As of August 21, 2026, most operational indicator measures remained below established response targets, and data for others were unavailable, indicating gaps in surveillance, contact tracing, laboratory testing, health care–seeking, isolation, and SDB capacity that limit control of the ongoing outbreak. 

    These missing data and operational gaps, together with continued geographic expansion of the outbreak, a high percentage of deaths occurring outside ETUs, and a low percentage of cases among persons previously identified as contacts, indicate uncontrolled expansion of the outbreak. 

    Public health response activities are complicated by a protracted complex humanitarian emergency in the eastern part of DRC, including armed conflict, limited health infrastructure, population displacement and mobility, and constraints on access to affected communities.

    Containment and control of the 2026 Ebola disease outbreak requires integration and coordination of at least five response areas: 

    1) expansion of community-based surveillance systems ensuring rapid investigation of alerts; 

    2) improvements in contact tracing completeness and timeliness; 

    3) expansion of treatment and isolation capacity in affected health zones; 

    4) increased laboratory testing capacity, enabling prompt case identification; and 

    5) ensuring SDBs in affected health zones.

    

    In addition, collecting robust, high-quality data regarding these operational actions is essential at the health zone level; CDC’s continued support to the DRC Ministry of Public Health and partners with improving data collection is critical. 

    Collecting data at the level of the health zone facilitates timely local outbreak response decisions. 

    Rapidly enhancing international humanitarian coordination and mobilizing global technical, operational, and other needed support are critical for accelerating the response and controlling the outbreak.

CDC 2026 Ebola Response International Epidemiology and Laboratory Task Force

Christine Atherstone, Amy Boore, Vance Brown, Jonathan Bryant-Genevier, Nirma Bustamante, Maestro Evans, James Fuller, Timothee Kinkela, John D. Klena, Thomas C. McHale, Elissa Meites, Emmanuel A. Mensah, Mpingulu Minlangu, Pierre Muhoza, Mike Park, Jaymin Patel, Satish K. Pillai, Anne Purfield, Logan Ray, Jessica N. Ricaldi, Katrin S. Sadigh, Dean Sayre, Trevor Shoemaker, Rachel Snyder, Christina Spiropoulou, Leisel Talley, Alison Todres, Sebastien Tshipamba, Amy Whitesell, Hailey Whitmire, Kristina Wielgosz, Emily Zielinski-Gutierrez, CDC; Democratic Republic of the Congo, Ministry of Public Health.

Corresponding author: Sascha Ellington, frk5@cdc.gov.

Source: 

Link: http://dx.doi.org/10.15585/mmwr.mm7535e1

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2nd meeting of #IHR EC on #epidemic of #Ebola #Bundibugyo virus disease in #DRC – Meeting report (WHO, August 29 '26)

28 August 2026 | Statement | Geneva 

    The Director-General (DG) of the World Health Organization (WHO) is hereby transmitting the report of the second meeting of the International Health Regulations (2005) (IHR) Emergency Committee (Committee) regarding the epidemic of Ebola disease caused by Bundibugyo virus (BVD) in the Democratic Republic of the Congo (DRC), held on Tuesday, 18 August 2026, from 12:00 to 17:00 CEST.

    The DG welcomes the Statement by the Committee, presented at the beginning of its report, and expresses his most sincere gratitude to the Chair, Members, and Advisors of the Committee.

    Concurring with the advice expressed by the Committee during the meeting, the DG determined that the BVD epidemic in the DRC continues to meet the criteria of a public health emergency of international concern (PHEIC), but not those of a pandemic emergency. Accordingly, on 24 August 2026, the DG, considering the advice offered by the Committee, issued temporary recommendations to States Parties, available here.  

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Statement by Committee

    The Committee commends the Government of Uganda for the rapid control of BVD transmission, with no new cases detected since 16 July 2026, and recognizes the major efforts being undertaken by the DRC, affected communities, WHO and national and international partners. Nevertheless, the Committee considers the continuing rapid growth and geographic expansion of the epidemic in the DRC to be of grave concern, requiring urgent, intensified and sustained action.

    As of 18 August 2026, approximately 5,000 BVD cases have been reported in the DRC. Available modelling suggests that substantial under-ascertainment may be occurring, with the true number of infections potentially three- to four-fold higher. Without a rapid change in the trajectory of transmission, the epidemic risks reaching a scale with profound national and regional consequences, with the potential for case numbers and deaths to exceed those seen in the 2013-2016 Ebola disease epidemic in West Africa. The Committee therefore emphasizes the need for urgent, decisive and coordinated action to control BVD transmission in the DRC.

    The BVD epidemic is occurring in the context of an already severe and complex humanitarian emergency. Areas with some of the highest BVD transmission burdens substantially overlap with areas affected by armed conflict, insecurity, population displacement and constrained humanitarian access.

    These conditions endanger affected populations and responders, impede community engagement, surveillance, contact tracing, safe and timely access to care, infection prevention and control (IPC), and other essential response operations.

    At the same time, disruption of essential health services risks increasing preventable deaths from malaria, diarrhoeal diseases, maternal causes and other conditions. Uncontrolled transmission also carries potentially serious consequences for neighbouring countries and for the social and economic stability of the Great Lakes region.

    The Committee emphasizes that communities must be at the center of the response. Erosion of trust in authorities and responders, insufficient community ownership, insecurity and operational and coordination weaknesses are major impediments to effective control. These challenges cannot be addressed through public health interventions alone. The response must be built with affected communities and supported by trusted local leaders and organizations, with transparent communication, meaningful participation and mechanisms through which community concerns rapidly influence response operations.

    The Committee notes that current epidemiological, clinical and genomic evidence does not indicate a fundamental change in the known biology, modes of transmission or clinical characteristics of Bundibugyo virus (BDBV). The priority, therefore, is to deliver science-based public health response interventions of proven effectiveness at sufficient speed, quality, coverage and scale.

    The Committee is deeply concerned that implementation of core essential public health response interventions has not yet consistently achieved the coverage and performance required to interrupt BVD transmission. 

    An immediate and drastic operational intensification and scale-up of response operations is required, potentially with an operational reset. 

    Particular priority needs to be given to: 

        - ensuring community engagement and community-based surveillance; 

        - rapid case detection, 

        - investigation and isolation; 

        - comprehensive contact identification and follow-up; 

        - IPC in BVD isolation and treatment centers, other health-care facilities and communities; 

        - safe and dignified management of deaths; 

        - timely laboratory diagnosis; and 

        - accessible, high-quality clinical care. 

    All these areas require intensification of efforts, and all should be viewed as essential components of an effective response. While none of these areas can afford to be neglected or deprioritized, the Committee identifies below specific areas requiring urgent action and particular focus.

    Effective vaccines and therapeutics against BVD, should they become available and be demonstrated to be safe and effective through rigorous clinical trials, could make an important contribution to reducing transmission, morbidity and mortality; however, they should complement rather than be a substitute for rigorous implementation of core public health measures.

    The response must be planned not only for the immediate term but for the sustained engagement that will be required over the coming months, or even years. This requires predictable financing, adequate human resources, secure access to communities, resilient supply chains, continuity of essential health services, and sustained national, regional and international political commitment.

    The Committee therefore calls for an immediate, unified and fully resourced intensification of the response, under the leadership of the Government of the DRC and with sustained regional and international support. The temporary recommendations issued by the DG should be translated into one integrated, time-bound and costed national action plan for the DRC, serving as the common framework for aligning the efforts and resources of the Government and national and international partners.

    The plan should establish clear responsibilities, measurable milestones and indicators; identify operational and geographic gaps; quantify the human, logistical and financial resources required; and include a companion gap analysis to guide urgent resource mobilization. Implementation should be reviewed frequently against agreed indicators and the evolving epidemiological situation, with rapid corrective action where milestones are not being achieved.

    Given the intersection between ongoing transmission, armed conflict, insecurity and restricted humanitarian access, the Committee emphasizes that high-level political engagement is urgently required to secure safe, sustained and unhindered access for epidemic-control operations that is being called for. 

    National, regional and international leaders should use all appropriate diplomatic and humanitarian channels to create the conditions necessary for effective implementation of comprehensive response measures. Where required, this should include arrangements for temporary cessations of hostilities or other humanitarian access measures that enable affected communities to receive essential health services and allow response teams to operate safely and effectively.

    The imperative is clear: interrupt BVD transmission rapidly, protect affected communities and health workers, maintain essential health services, prevent further geographic and cross-border spread, and mobilize the political, operational and financial support necessary to bring the epidemic under control.

    The Committee calls for particular focus on the following urgent priority interventions:

        § Drastic scale-up of trust-building and community engagement through trusted communication channels and local actors, including local leaders, religious leaders, traditional healers and survivors, to support community participation in fostering the acceptance of public health measures, including early detection, case referral, contact tracing, safe and dignified burial practices, and adoption of protective behaviours.

        § Drastic scale-up of IPC measures to prevent transmission in BVD isolation and treatment centers, other healthcare settings, and, in some circumstances, at home in the community. With regard to the latter, although it is not realistic to expect community members to be able to maintain the same level of application of IPC measures as in healthcare settings, it must be recognized that, for myriad reasons, many sick persons cannot or will not seek care in health care facilities. Until clinical care capacity can be augmented, along with the requisite enhanced security and community trust to motivate and permit sick persons to seek care, steps to limit transmission in the home, such as distribution of personal protective equipment, materials and disinfectants, may reduce transmission risk and morbidity, and may also represent a conduit for greater community engagement.

        § Drastic scale-up of BVD isolation and treatment centers staffed by a specifically trained workforce, with appropriate provision of personal protective equipment and materials.

        § In-depth analysis or research to identify and characterize BVD transmission dynamics associated with specific settings, including related modes of BVD transmission (e.g. caretaking in the home, hospital, or at traditional healers, re-use of needles). A better understanding of the epidemiology of the epidemic is essential for the implementation of effective interventions.

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The Annex to this Report records the views of one Member of the Committee in relation to the “Statement by the Committee”.

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Proceedings of the meeting

    All 12 Members of, and five Advisors to, the Committee participated in the meeting convened by teleconference, via Zoom, on Tuesday, 18 August 2026, from 12:00 to 17:00 CEST.

    The DG joined in person and welcomed the participants, including Government Officials designated to present their views to the Committee on behalf of the three invited States Parties – the DRC, France and Uganda. The opening remarks by the DG are available here.

    The Representative of the Office of Legal Counsel briefed the Members and Advisors on their roles and responsibilities and identified the mandate of the Committee under the relevant provisions of the IHR. 

    The Ethics Officer from the Department of Compliance, Risk Management, and Ethics proceeded with the rollcall and provided the Members and Advisors with an overview of the WHO Declaration of Interests process. 

    The Members and Advisors were made aware of their individual responsibility to disclose to WHO, in a timely manner, any interests of a personal, professional, financial, intellectual or commercial nature that may give rise to a perceived or actual conflict of interest. 

    They were additionally reminded of their duty to maintain the confidentiality of the meeting discussions and the work of the Committee. Each Member and Advisor was surveyed, with no conflicts of interest identified.

    The meeting was handed over to the Chair who introduced the objectives of the meeting, which were to provide views to the DG on whether the event continues to constitute a PHEIC, including a pandemic emergency, and to provide views on the proposed temporary recommendations.

Session open to representatives of States Parties invited to present their views

    Representatives of the DRC and Uganda updated the Committee on the BVD epidemiological situation in their countries, their current response efforts, needs and challenges. Ahead of the meeting, France submitted a written statement to the Committee regarding an imported BVD confirmed case from the DRC.

    The WHO Secretariat presented a comparative assessment of the indicators associated with each of the three criteria defining a PHEIC between 17 May 2026, when the PHEIC was determined, and 12 August 2026, as well as the indicators associated with each of the criteria defining a pandemic emergency, as per Article 1 - Definitions of the IHR. The WHO Secretariat also presented an overview of health operations and the scale up strategy in response to the BVD epidemic.

With respect to the indicators associated with the PHEIC criteria, the following assessment was presented.

1. Extraordinary

1.1. Growth rate (effective reproductive number (Rt))

    On 17 May 2026, the growth rate could not be calculated, though it was understood to be very high, given the orders-of-magnitude increase in the number of confirmed cases since then. Case-based estimates now suggest a doubling time of 52 days and an Rt of 1.24; however, low case ascertainment means these figures are likely to understate true transmission. Deaths are considered a more reliable indicator of epidemic growth, given higher relative ascertainment of fatal outcomes. Based on mortality data, the estimated doubling time is 21 days, with an Rt of 1.55. Triangulation across multiple methods and data sources further estimates that the true size of the epidemic is 3 to 4 times larger than what is reflected by surveillance data. Growth rate was assessed as ‘very high’ at the time the PHEIC was determined and continues to be assessed as ‘very high’ as of 12 August 2026, with confidence improving from ‘low’ to ‘moderate.’

1.2. Within country geographical spread (number of health zones with BVD in the DRC)

    On 17 May 2026, BDBV was known to be present in three health zones in the DRC. As of 12 August 2026, its presence had expanded to 55 health zones, 49 of which had active transmission. The geographic mapping of confirmed BVD cases likely understates the real extent of the spread, as some affected areas remain outside government control or are subject to insecurity limiting surveillance and response operations. Forecasting identifies 15 health zones at highest risk of further expansion in the coming week, four of which border Uganda, South Sudan, and Rwanda. The indicator increased from ‘moderate’ on 17 May 2026 to ‘high’ on 12 August 2026, with the level of confidence remaining ‘moderate’.

1.3. Challenges to contact tracing (proportion of BVD cases from listed contacts)

    Challenges with contact tracing persist unchanged. While the follow-up of listed contacts stands at approximately 80%, the average of 13 listed contacts per BVD case is far lower than that observed in previous viral hemorrhagic fever outbreaks. This results in only approximately 20% of BVD cases being identified through the follow up of listed contacts, and 40% of the BVD cases eventually linked to a chain of transmission. Challenges to contact tracing were assessed as ‘very high’ on 17 May 2026 and they remained ‘very high’ as of 12 August 2026. The level of confidence of those assessments moved from ‘low’ (17 May 2026) to ‘moderate’ (12 August 2026).

1.4. Severity (case fatality ratio (CFR))

    Early in the epidemic (around mid-May 2026), the crude CFR appeared as low as 20%, as the numerator did not include several deaths among persons under investigation for suspected BVD. As surveillance improved, as of 12 August 2026, the crude CFR stands at approximately 46%, notwithstanding persisting limitations in data quality. As expected, the CFR varies by age, with no meaningful difference observed by sex. The assessment of the severity as ‘high’ remained unchanged between 17 May and 12 August 2026, with the level of confidence moving from ‘low’ to ‘moderate.’

1.5. Disruption to health services (various)

    Before the BVD epidemic was detected, health services in the areas with current BVD transmission were already under strain from a deteriorating humanitarian situation, compounded by funding withdrawals, attacks on healthcare facilities, and supply chain disruptions. According to the most recent assessment conducted after the BVD epidemic was detected, the use of health care services has fallen by more than 40% in some of the areas with BVD transmission. Despite that, the observed incidence of malaria, cholera, and trauma cases remain high. In Ituri Province, maternal deaths have doubled since May 2026, currently averaging more than six per week. As of 17 May 2026, the disruption to health services was assessed as ‘moderate’ and, due to its worsening, it was assessed as ‘high’ as of 12 August 2026. Due to the scarcity of data, the level of confidence in those assessments remained ‘low’ and unchanged between 17 May 2026 and 12 August 2026.

2. International spread

2.1. Number of States Parties with BVD cases (imported cases, including resulting in limited local transmission)

    Historically, imported cases of Ebola virus infection have been reported during past outbreaks. However, only in a very limited number of instances have imported cases resulted in onwards transmission - limited to a very small number of cases – in States Parties outside Africa. In the context of the ongoing BVD epidemic in the DRC, modelled estimates indicate the risk of BVD spread to States Parties outside Africa remains very low. With respect to the risk of BVD spread from the DRC to other States Parties in Africa, modelled estimates indicate that this is significant for States Parties sharing land borders with provinces of the DRC with BVD transmission. Beside the possibility of reintroduction of BVD into Uganda, the risk is highest for South Sudan, reflecting its connectivity with the DRC. It is noted that the Central African Republic was not included at the time the modelled estimates were calculated.

    As of 17 May 2026, two States Parties (the DRC and Uganda) had detected BVD cases, with BVD cases in Uganda resulting from importations from the DRC and limited onwards local transmission. At that time the indicator was assessed as ‘low’. As of 12 August 2026, active BVD cases were reported only in the DRC, following control of BVD transmission in Uganda. The single imported BVD case detected in France did not result in onward transmission. The assessment of this indicator therefore remains ‘low’. Between 17 May and 12 August 2026, the level of confidence moved from ‘moderate’ to ‘high.’

2.2. Gaps in preparedness in States Parties sharing land borders with the DRC (and Uganda) (composite percentage)

    States Parties considered in this assessment are those sharing land borders with the DRC, as well as with Uganda, given the detection of imported BVD cases in Uganda early in the epidemic, and include Angola, Burundi, Central African Republic, Kenya, Republic of Congo, Rwanda, South Sudan, Tanzania and Zambia. In the context of quarterly readiness self-assessment, coordinated by the WHO Regional Office for Africa, a specific BVD-readiness assessment was conducted in the third quarter of 2026. The average readiness score of that assessment, encompassing 11 readiness domains and expressed in percentage, is as follows: Central African Republic - 38%; Republic of Congo - 50%; Tanzania - 53%; Angola - 64%; South Sudan - 65%; Zambia - 70%; Rwanda - 94%. There are no data available for Burundi and Kenya. The assessment of this indicator as ‘high’ remained unchanged between 17 May and 12 August 2026, with the level of confidence remaining ‘moderate’.

3. International cooperation

3.1. In-country response capacity exceeded (expert judgement based on operational outputs and epidemiological data)

    Since the BVD epidemic was detected in the DRC, the national response capacity has been scaled up. As of 12 August 2026, there were 21 laboratories with BDBV testing capacity, and approximately 1000 beds for the treatment of BVD cases. Although these figures may represent the fastest scale-up on record and reflect a very large-scale operational response, the late detection of the epidemic and the resulting unprecedented growth in BVD cases have outpaced the combined response capacity of the Government and partners. For example, the estimated number of beds needed for the treatment of BVD cases is 3000. Furthermore, there is a need to maintain essential health and humanitarian services amid severe access constraints, large-scale displacement and logistical disruptions, including the closure of the airports in Goma and Bukavu. The closure of these airports has hindered the delivery of essential supplies and led to recurrent stock-outs, further increasing the risk of morbidity and mortality. While this indicator was assessed as ‘high’ on 17 May 2026, in light of mounting humanitarian pressures, dwindling resources and the pace of epidemic growth, it was assessed as ‘very high’ on 12 August 2026, with the level of confidence remaining ‘high’.

3.2. Need for coordination of international response (expert judgement based on response operations data)

    Since the BVD epidemic was detected in May 2026, a continental preparedness and response plan was developed to support the implementation of national plans and coordinate the work of more than 30 named partners, with all partner response activities coordinated under a Continental Incident Management Support Team. Under that framework, a joint financial tracking mechanism has been established. As of 12 August 2026, there were 94 partners reporting engagement in the BVD response, across multiple technical pillars, with operations concentrated in Ituri, North Kivu and South Kivu Provinces in the DRC, leaving critical gaps in partner support elsewhere in the country. The WHO Secretariat has deployed 274 staff, including through partner networks, against a target of 455. The overall need for coordination of the international response was assessed as ‘high’ on 17 May 2026, and remained such as of 12 August 2026, with the level of confidence remaining unchanged as ‘high’.

3.3. Access to BVD-specific countermeasures

    As was the case when the BVD epidemic was detected in May 2026, as of 12 August 2026, no BVD-specific countermeasure is licensed. This indicator therefore remains not applicable.

    Members of, and Advisors to, the Committee then engaged in questions and answers with States Parties’ Representatives and the WHO Secretariat.

Deliberative session

    Following the session open to invited States Parties, the Committee reconvened in a closed session to examine the questions in relation to whether the event constitutes a PHEIC, including a pandemic emergency, and to consider the temporary recommendations drafted by the WHO Secretariat in accordance with IHR provisions.

    The Chair reminded the Committee Members of their mandate and recalled the definitions of PHEIC and pandemic emergency, as per Article 1 - Definitions of the IHR.

    Except for one Member, the Committee expressed the view that the BVD epidemic in the DRC continues to constitute a PHEIC but does not meet the criteria of a pandemic emergency, and that the DG be advised accordingly.

    The Committee subsequently considered the temporary recommendations to States Parties proposed by the WHO Secretariat.

    The Committee, ahead of its meeting, had received proposed temporary recommendations drafted by the WHO Secretariat in accordance with the provisions of the IHR, and subsequently offered its insightful advice.

    Specifically, the Committee called for the formulation of temporary recommendations stressing the urgency of immediately intensifying core interventions, including a drastic operational scale-up of human resources, as well as for planning efforts to sustain the response to the BVD epidemic over a prolonged period.

Conclusions

    The Executive Director of the WHO Health Emergency Preparedness and Response Programme, on behalf of the DG, expressed his gratitude to the Committee’s Officers, its Members and Advisors and closed the meeting.

===

Annex

    In accordance with paragraph 4.12, under Reports on Meetings of Committees in the WHO Regulations for Expert Advisory Panels and Committees, the Committee hereby records the divergent views expressed by one Member with respect to the “Statement by the Committee”.

    While the Statement reflects the deep concern expressed by the other Members of the Committee in the course of formulating their advice to the Director-General on whether the event constitutes a public health emergency of international concern, one Member indicated that the Statement extends beyond the terms of reference of the Committee, as set forth in Articles 12, 17, 48 and 49 of the IHR.

    The specific reasons provided by the Member relate to the following aspects addressed in the Statement: “operational management of the response, national response planning, resource allocation and mobilization, political or diplomatic engagement, or humanitarian and security arrangements.”

Source: 

Link: https://www.who.int/news/item/28-08-2026-second-meeting-of-the-ihr-emergency-committee-on-the-epidemic-of-ebola-bundibugyo-virus-disease-in-the-democratic-republic-of-the-congo---meeting-report

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#Ebola disease caused by #Bundibugyo virus - #DRC (WHO, August 28 '26): 5,794 cases and 2,786 deaths

 

Situation at a glance

    Since the last Disease Outbreak News was published on 14 August 2026, the outbreak has spread from 54 to 60 health zones. 

    The number of affected provinces stands at six out of 26 provinces of the country: Bas-Uélé, Haut-Uélé, Ituri, North Kivu, South Kivu, and Tshopo. 

    Six additional health zones reported cases since the last update - Ganga and Viadana health zones in Bas-Uélé province, Biena, Manguredjipa, and Mutwanga in North Kivu, and Tshopo health zone in Tshopo province. 

    As of 26 August 2026, a total of 5794 confirmed cases, including 2786 deaths, have been reported, corresponding to a crude case fatality ratio (CFR) of 48.1%. 

    These figures demonstrate a substantial increase in the scale and geographic extent of the outbreak over the past three months. 

    The crude case fatality ratio of 48% underscores the severity of the disease and ongoing challenges related to timely case detection, access to and quality of clinical care, and effective interruption of viral transmission. 

    Delays in recognizing cases increase the likelihood of onward transmission within households, communities and healthcare facilities. 

    The outbreak remains a public health emergency of international concern, following the advice of Emergency Committee meeting convened on 18 August.

Description of the situation

    Since the previous Disease Outbreak News was published on 14 August 2026, additional confirmed cases and deaths of BVD have been reported only in the Democratic Republic of the Congo.  

    Cumulatively as of 26 August 2026, 5815 confirmed cases have been reported: 5794 in the Democratic Republic of the Congo (including two cases diagnosed in the Democratic Republic of the Congo and subsequently treated in Germany), 20 in Uganda and one in France. 

    A total of 2788 deaths have been reported, including two in Uganda. 

    As of 26 August, at least 1314 patients have recovered, including 1293 in the Democratic Republic of the Congo, 18 in Uganda, two in Germany and one in France.  

    As of 27 August, the 42-day enhanced monitoring period, as per international guidance, has been completed in both France and Uganda.  

    The continuing intensity of transmission in the Democratic Republic of the Congo means that the risk of further exportation across international borders remains. 

    Entry and exit health screening and surveillance measures are in place at airports, ports and official land border crossings; however, movement through informal border crossing routes may occur, presenting an ongoing risk of virus exportation, importation and onward transmission. 

    Therefore, cross‑border collaboration, and sustained surveillance and preparedness are essential to prevent further regional spread and ensure an effective public health response. 

    On 27 August, vaccination of health care workers using the Ervebo vaccine was initiated in the Democratic Republic of the Congo in some areas, including in Kisangani, Tshopo province. 

    Although Ervebo is a safe vaccine, and effective against Ebola virus disease, it is not known whether it provides protection against the Bundibugyo virus in humans. 

    Thus, starting a clinical trial of the vaccine, alongside this wider use, is key to provide important new evidence and inform future use of the vaccine. 

    The second IHR Emergency Committee meeting regarding the epidemic of Ebola Bundibugyo virus disease in the Democratic Republic of the Congo took place on 18 August. 

    Following the advice of the Committee, the Director-General agreed that the ongoing outbreak remains a Public Health Emergency of International Concern, and issued updated temporary recommendations to countries. 

(...)

Democratic Republic of the Congo  

    Since 14 August 2026 when the last Disease Outbreak News was published, an additional 1129 confirmed cases, including 602 confirmed deaths, have been reported in the Democratic Republic of the Congo. 

    Although part of this increase likely reflects expanded surveillance, enhanced laboratory testing, improved diagnostic capacity, and periodic data backlog reconciliation, the sustained rise in number of cases and deaths are the result of continued transmission and substantial outbreak expansion. 

    As of 26 August 2026, a total of 5794 confirmed cases, including 2786 deaths (CFR 48.1%), have been reported in the Democratic Republic of the Congo. 

    To date, 1293 patients have recovered. 

    Cases have been reported from 60 health zones (HZ) across six provinces. Ituri has 28 health zones affected out of 36, followed by North Kivu (15/34), Haut-Uélé (6/13), Tshopo (7/23), South Kivu (1/34) and Bas Uélé (3/11). 

    The most recently affected province, Bas-Uélé, started reporting cases since 12 August. 

    The most recently affected health zones are Biena and Manguredjipa in North Kivu province. 

    As of 26 August, of the 60 affected health zones, 81 new confirmed cases were reported in the last 24 hours from 19 health zones in Ituri, North Kivu, Haut-Uélé, and Tshopo provinces. Ituri remains the epicentre of the outbreak, with 4802 confirmed cases reported since the start of the outbreak, including 52 new confirmed cases reported in the last 24 hours, as of 26 August. 

    Nord-Kivu is the second most affected province, with a cumulative number of 775 confirmed cases, including 22 reported in the last 24 hours, as of 26 August. The highest CFR (68%) in this outbreak has been reported from North Kivu province; the reasons for this high CFR are under investigation. 

    The number of individuals requiring contact monitoring has also increased substantially as the outbreak has expanded. As of 26 August, the proportion of contacts followed up in the last 24 hours is at 82.3% (22 091 seen out of 26 850 to follow up). The large number of contacts reflects the scale of potential exposure within affected communities. 

    The outbreak is unfolding in a conflict-affected humanitarian context marked by insecurity, armed violence, and large-scale displacement. 

    More than 26 million people face acute food insecurity, and an estimated one million internally displaced people live in Ituri Province alone. Insecurity and displacement disrupt access to health care and essential services, restrict access for response teams, and impede surveillance, case investigation and contact follow-up. 

    Overcrowding, limited water, sanitation and hygiene services, and restricted access to healthcare in mining communities, informal settlements and sites for internally displaced people further hinder early detection, infection prevention, and appropriate care. These conditions also make it harder to implement response measures consistently and to reach affected populations.  

Figure 2: Number of confirmed Bundibugyo virus disease cases in the Democratic Republic of the Congo, by date of notification, as of 26 August 2026

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Figure 3: Number of deaths among confirmed Bundibugyo virus disease cases in the Democratic Republic of the Congo by date of notification, as of 26 August 2026

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    Between 18 May and 28 August 2026, enhanced public health intelligence conducted by WHO identified 76 Ebola-related signals across 23 countries and territories, supporting rapid verification, risk assessment and information sharing with national authorities through IHR National Focal Points. Most signals, 92% (70/76), including suspected cases among travellers and health-care workers and reports circulating in public sources, were subsequently ruled out through investigation and laboratory testing. The remaining six were confirmed as Ebola events. 

Epidemiology

    Bundibugyo virus disease (BVD) is a severe Ebola disease caused by the Bundibugyo virus, one of the Orthoebolavirus species. It is a zoonotic disease, with fruit bats suspected to be the natural reservoir. 

    

    Human infection is thought to occur through close contact with the blood or secretions of infected wildlife, such as bats or non-human primates, and it subsequently spreads from person-to-person through direct contact with the blood, secretions, organs, or other bodily fluids of infected individuals or contaminated surfaces and materials. Transmission is particularly amplified in health-care settings when IPC measures are inadequate and during unsafe burial practices involving direct contact with deceased individuals. 

    The incubation period for BVD ranges from two to 21 days, and infected individuals are not infectious until symptom onset. Early symptoms such as fever, fatigue, muscle pain, headache, and sore throat are non-specific, which complicates clinical diagnosis and can delay detection. These symptoms then progress to gastrointestinal symptoms, organ dysfunction, and, in some cases, haemorrhagic manifestations. 

    CFRs in the past two BVD outbreaks, reported in Uganda and in the Democratic Republic of the Congo in 2007 and 2012, were 30% and 50%, respectively. 

    Differentiating BVD from other endemic febrile illnesses such as malaria is challenging without laboratory confirmation using PCR or antigen- or antibody-based assays. Outbreak control relies on rapid case identification, isolation and care, contact tracing, safe burials and strong community engagement, as no approved vaccines or specific treatments currently exist for BVD. 

    Since first detected in May 2026, this BVD outbreak has rapidly evolved into a large and geographically expanding epidemic in the Democratic Republic of the Congo, with sustained transmission, high mortality and an increasing risk of further international spread. The current outbreak is the second documented Bundibugyo virus disease outbreak in the country, after the 2012 outbreak, and the largest Ebola disease outbreak ever recorded in the Democratic Republic of the Congo irrespective of Ebola virus species. The population at greatest risk of exposure is concentrated in communities living in and moving through areas with active transmission.  

(...)

WHO risk assessment

    On 14 August 2026, WHO reassessed the risk of the outbreak of BVD to incorporate newly available information. The risk for countries sharing land borders with the Democratic Republic of the Congo was separated from the risk for other countries in the African Region. 

    The risk in the Democratic Republic of the Congo was assessed as very high due to ongoing transmission and the continued expansion of the outbreak into new health zones, increasing the potential for further national and regional spread. The main considerations supporting this assessment include the substantial increase in the number of cases and considerable geographic extension of the outbreak since the previous risk assessment, and potential further increase in CFR as additional deaths are investigated and outcomes are established. In addition, reported transmission among healthcare workers, ongoing conflict and insecurity, laboratory capacity constraints, and absence of licensed vaccine or specific antiviral treatment were also considered as factors maintaining the very high risk. 

    The risk for countries sharing land borders with the Democratic Republic of the Congo was again assessed as high due to sustained population mobility linked to cross-border trade and mining activities, variation in capacities and experience of BVD response, and variable levels of readiness. Uganda, the Central African Republic and South Sudan are of particular concern for importation given their proximity, high population mobility and connectivity with areas of the Democratic Republic of the Congo currently experiencing intense transmission. For the Central African Republic and South Sudan, these risks are further compounded by high humanitarian needs, population displacement, insecurity and underlying limitations in health-system capacity. 

    The risk for the rest of the African region and at the global level was again assessed as low. 

(...)

Source: 

Link: https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON616

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Predicting the #Risk of Avian #Influenza #Zoonosis using Viral #Genome Sequencing Data

 

Abstract

Avian Influenza viruses (AIVs) infect a broad host range despite having a natural reservoir in wild aquatic birds. Whilst most strains stay within their host species, some break the species barrier through genetic adaptations. We are most concerned about zoonotic cases, where a human becomes infected. Despite these events being rare, they are associated with high mortality and introduce the risk of onward human-to-human transmission of AIV. As a novel pathogen within the human population, this could have pandemic potential. Using genetic composition features for 8 AIV proteins drawn from viral sequence data, we employ machine-learning algorithms to classify AIV cases as zoonotic or not. These genetic features encode host 'signatures' which can indicate zoonosis and include frequency measures such as dipeptide composition and amino acid physiochemical properties. We consistently find XGBoost to outperform all other algorithms. We optimise parameters for ten classification models: one for each of the 8 proteins and two combined models. Following this, we show that a multi-model approach gives the best performing prediction for AIV zoonosis. We have identified all 8 proteins as having a role in predicting zoonotic transmission. Of particular importance is the PB2 and HA proteins, with specific amino acid physiochemical properties such as charge, secondary structure and hydrophobicity amongst the most indicative features in our combined models. Our alignment-free computational study can identify AIV cases still within avian hosts which are genetically closest to zoonotic AIV cases, thereby identifying the cases most likely to cross the species barrier. In a resource limited environment, our model could be used to quickly identify high priority cases for further investigation.

Competing Interest Statement

The authors have declared no competing interest.

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.08.21.746166v1

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#Mpox, Multi-Country #Outbreak - Rapid #risk #assessment V7 (#WHO, August 25 '26)

{Summary}

    ° Date and version of current assessment: 18 August 2026, v7

    ° Overal Global Risk statement: 

        § This global rapid risk assessment (RRA) assessesthe current public health  risk associated with the 2024 upsurge of mpox in Africa, in the context of the  continuing global occurrence of mpox in all regions since 2022, with a focus on  updates since the previous RRA in February 2026. 

        § The overall public health risk  posed by mpox remains unchanged from the last RRA. 

Global overview

    As of 30 June 2026, the monkeypox virus (MPXV) continues to spread  globally, causing both localized and extended mpox outbreaks driven by multiple  MPXV clades (Ia, Ib, IIa, and IIb) in diverse settings. The recombination of MPXV clades has also been documented, with the two previously reported cases  of a recombinant clade Ib/IIb MPXV strain detected in the United Kingdom of Great Britain and Northern Ireland in late 2025 and India in January 2026,  and one additional case reported in Qatar since the last RRA.

    Globally, from 1 January 2022 to 30 June 2026, 145 countries and  territories across all WHO regions reported 188 847 confirmed cases of mpox,  with 521 deaths [case fatality ratio (CFR) – 0.3%] and including two  additional countries: Comoros and Guinea-Bissau. 

    Since the last RRA, an additional 10 908 confirmed cases, 44 deaths,  and an average of 420 new confirmed mpox cases per week have been reported  across all affected countries. 

    As with the previous version, this RRA assesses the risk for three population groups; 

        i) global risk for individuals with multiple sexual partners, 

        ii) risk for children in mpox historically endemic areas where risk of zoonotic  transmission continues, and 

        iii) global risk for all other individuals. Updates in understanding of mpox  epidemiology within these groups are described herein.

Individuals with multiple sexual partners – global risk

    Since the start of the global mpox outbreak in 2022, sexual activity in  linked sexual networks has been the primary driver of sustained transmission and  geographic spread, particularly in newly affected areas. The major and  predominant contribution of sexual transmission, whether linked to  heterosexual or same-sex contact, to the introduction, spread and  establishment of mpox in communities has been recognized across all affected  settings. 

    Outside the WHO African Region, over 87% of reported cases have been among men who have sex with men (MSM), with transmission driven by  spread among individuals with multiple sexual partners in a short time span  and/or frequent partner change. 

    Outbreaks are commonly linked to a sex-on-premises location or event.  In Africa, transmission has often been reported to involve sex workers and their  clients, long-distance drivers and other sexual networks where people have  multiple partners and/or frequent partner change. In Africa, most transmission  appears to be heterosexual.

    In networks characterized by multiple partners and/or frequent partner  change over short periods (days to a few weeks), the secondary attack rate for  sexual contact may be high (estimated at 73% in some settings), facilitating epidemic spread. This pattern was observed during the initial spread of  clade IIb MPXV among MSM communities and more recently clade Ib and IIb  MPXV outbreaks in Africa and elsewhere, with amplification in key populations  such as female sex workers and their clients as well as others with multiple  partners, often in different locations. The recently identified recombinant clade  Ib/IIb strain of MPXV has also been identified in this group with similar risk factors  related to sexual contact. This risk group therefore includes people with multiple or frequently changing sex partners, including those with higher-risk  sexual behaviours.

    Sexual contact transmission likely occurs during various stages of  infection, including pre-symptomatic or less apparent stages, the duration of  which can vary between individuals. People with few or mild genital lesions might not recognise the infection. Studies have shown that the virus can be  present in genital and anal mucosae, as well as in seminal and vaginal fluids  of symptomatic infected individuals. Emerging data suggests that viral  shedding from the genitals may occur up to four days before symptom onset,  potentially contributing to undetected sexual contact transmission. This could  explain the persistence of the virus in communities and the challenges  encountered in interrupting human-tohuman transmission, while the contribution  of asymptomatic viral carriage to transmission remains unclear.

    In most healthy adults of this group, mpox is often self-limiting.  However, severe disease, including disabling complications, secondary infections,  long-term sequelae and death, continues to occur most particularly but not exclusively in people living with advanced HIV disease or uncontrolled HIV  infection, as well as other immunocompromising conditions. While overall case  fatality has remained below 1% in most settings, up to 15-fold or higher fatality has been observed among individuals with immunosuppression, as well as in vulnerable infants, and particularly neonates  in some settings. Notably, recent data from the African setting support  observations elsewhere that people living with HIV who have suppressed viral loads and preserved CD4 counts experience mortality equivalent to HIV-negative individuals, indicating that the HIV-associated  mortality risk is largely modifiable and deaths are preventable through sustained  viral suppression and immune reconstitution. Although most people living with HIV globally are on antiretroviral therapy, significant and growing gaps in  diagnosis and treatment persist in several lowand middle-income settings, with  26.3 million people estimated to be living with HIV in Africa in 2025, of which over 20% either do not know their status, are not on antiretroviral therapy or are  not successfully virally suppressed, a situation exacerbated by recent funding cuts  to HIV control programmes in many countries. In many contexts, over half of mpox cases are reported among people living with HIV, adding  more complexity to the convergence of risks faced by this group (risk of infection,  risk of severe disease, and risk of poorer health service access).

    Most countries globally have activated outbreak responses, including  surveillance, case investigation, contact tracing, case management, and infection  prevention and control. However, control efforts have been impeded when sexual contact transmission or other risk factors are not adequately recognized, or  when risk communication and community engagement do not effectively reach  key populations and other individuals within sexual networks. Furthermore, countries are increasingly tasking HIV/STI control programmes –  themselves heavily constrained by recent funding cuts – with participating in or  leading the response, as well as activating immunization policies and programme  capacity.

    While targeted mpox vaccination has been implemented for groups at  higher risk of mpox exposure in many countries in high and low-income settings,  including administration of more than two million doses in Africa, coverage  remains uneven or partial and most individuals in this group remain susceptible to  MPXV infection, particularly in countries outside Europe and North America. In  addition, younger cohorts are continually entering sexually active age groups.

    The duration and level of protection conferred by prior infection and/or vaccination remains uncertain. 

    Overall, transmission in these groups at higher risk is ongoing and likely  to continue to spread geographically, which can be expected to lead to  severe outcomes among immunocompromised individuals, thus focusing  risk of spread among individuals with multiple partners in interconnected sexual  networks who may not be aware of risk, and the risk of complications and death  among vulnerable individuals. 

    The overall public health risk for individuals with  multiple sexual partners is, therefore, assessed as moderate.

Children in historically endemic areas – local risk

    In historically endemic areas in West and Central African countries,  where viruses continue to circulate in animal hosts and zoonotic spillover  continues to occur, particularly in the Democratic Republic of the Congo, the  highest number of mpox cases and incidence of deaths has been documented  among young children (<5 years). Surveillance and diagnostic capacities in these  settings remain suboptimal and have continued to decline in 2026, making the interpretation of available data challenging.

    Among individuals younger than 50 years in the Democratic Republic of the Congo, age-specific mpox incidence appears broadly comparable across age  groups, largely reflecting the underlying age distribution of the population.  However, case fatality among suspected mpox cases in children under five years of age (CFR 3.0%) is higher  than that observed among individuals aged  five to 15 years (CFR 1.9%), and almost twice that observed among  individuals aged 15 years and older (1.7%). Of note, the case fatality ratio in  historically endemic areas of the Democratic Republic of the Congo remains much  higher across all age groups than elsewhere (about 7 to 20-fold higher). This may  arise from specific vulnerabilitiesincluding delayed or limited access to appropriate  health care, compounded by concomitant health risks, such as  malaria, varicella, measles, malnutrition, and complications of mpox such as  dehydration and secondary infections. This higher fatality is particularly observed  in infants and young children, who are largely immunologically naïve. At present,  mortality data from this setting are largely drawn from syndromic surveillance  and multiple studies are underway to better describe the risks  associated with mpox in these settings.

    While targeted vaccination has supported outbreak response, in the  absence of established vaccination programmes against mpox and limited access  to early and appropriate healthcare, children and pregnant women in the affected  settings are likely to continue experiencing elevated health risks from  mpox and MPXV infection.

    The risk of geographic spread associated with non-sexual contact transmission is predominantly local. Available data indicate secondary attack  rates of less than 20% following non-sexual household contact, suggesting that  while children are vulnerable to more severe disease, and outbreaks in schools  have been documented , children generally appear to have a limited role in  driving viral spread. In addition, children have not often been reported as a source  of introduction of mpox in new areas, and their contribution to wider  geographic or cross-border spread remains negligible, compared to spread among adults exposed through sexual contact.

    Most historically endemic areas are rural forested territories, where  there is a risk of insufficient control capacities of outbreak response, particularly  now as countries transition from an acute outbreak response approach to a  longerterm disease control programme. Mpox programmes in these settings have  previously been greatly under-resourced and will increasingly need to rely on  preventive strategies and routine care capacity.

    Overall, in the absence of vaccination programmes for mpox in  historically endemic areas, and resources for national programmes conducting  outbreak response activities, the virus will likely continue to circulate,  disproportionately affecting younger children. 

    The overall public health risk for children in historically endemic areas is,  therefore, assessed as moderate.

All other individuals – global risk

    For individuals outside the above two risk groups, the overall risk of acquiring mpox is lower. While illness in the general population is typically mild  and self-limiting, with most cases requiring only supportive care and no  hospitalization, severe disease and death can also occur, albeit less commonly.  While the risk of severe outcomes is much higher among individuals with  underlying immunocompromising conditions, these persons generally represent a  small proportion of cases reported in recent outbreaks, and thus the majority of  cases with complications or deaths may actually occur in persons without immune  suppression in some settings. As noted above, case fatality in historically endemic  areas of the Democratic Republic of the Congo remains much higher across all age  groups than elsewhere (about 7 to 20-fold higher). More research is needed  to characterise less studied risk factors for severe disease. 

    Some data suggest that adults vaccinated before the cessation of routine smallpox vaccination worldwide , in 1980 or earlier in many  countries, are likely to retain partial cross-protective immunity and present with  lower disease severity.

    While breakthrough cases of mpox have been documented in some older  previously vaccinated persons, epidemiological data indicate that few mpox  deaths have been reported in this group. New cases of mpox with clade Ib  MPXV in various regions have predominantly been associated with sexual contact  in people with a history of travel to outbreak-affected areas who developed  symptoms just prior to or upon return. Spread through sexual networks from  some cases has ultimately led to the establishment of community transmission of  clade Ib MPXV in several countries outside Africa.

    Overall, the spread of clade Ib MPXV in newly affected areas has remained largely confined to groups at risk. Since the start of the global  outbreak in 2022, the general population has not been widely affected by ongoing  circulation of clade IIb MPXV in high income settings, nor has it been implicated in  mpox introduction or establishment in new geographic areas. Secondary  transmission to non-sexual contacts has remained limited. Thus, individuals in this  risk group (“all other individuals”) affected by clade IIb have mainly been  infected through household or occupational contact, characterized by low  secondary attack rates and limited onward transmission. Nonetheless, explosive  outbreaks in West Africa have demonstrated that all age groups can be  significantly affected such that continued vigilance is required for all mpox clade  outbreaks in different settings. Within this broad group which includes most  people, there are also other individuals in settings where there is a higher risk of  onward mpox transmission, such as those in internally displaced person (IDP) and  refugee camps and other congregate, overcrowded settings. Furthermore,  some more vulnerable individuals are considered to face a higher risk of severe  disease and poorer disease outcomes if they fall ill, particularly pregnant  individuals, neonates, and infants. Poor outcomes have been documented among  pregnant individuals and their unborn children, including spontaneous  abortions, missed abortions, still births, congenital mpox and early neonatal  death, with recent studies reporting these adverse outcomes in about half of  pregnant individuals followed up. The healthcare-associated clade Ib mpox outbreak among neonates and infants in Pakistan in early 2026 which  resulted in a CFR higher than 20% also demonstrated that mpox transmission can  lead to severe consequences in highly vulnerable populations. In this instance,  mpox in a neonatal intensive care setting resulted in rapid amplification and disproportionate impact in neonates and infants.

    Public health control measures such as laboratory confirmation, rapid  contact tracing and isolation have generally been sufficient to manage mpox in the  general population, notably in high-income settings. Nonetheless, partner  notification strategies should supplement classic contact-tracing to reach non- disclosed sexual partners. Vaccination has been prioritized for groups at higher  risk of exposure with the intent to prevent and stop transmission. Where vaccines  have, in some settings, been mainly offered to health workers for their individual  protection, this strategy builds confidence and quality of care but cannot be  expected to play a major role in stopping outbreaks.

    In all settings therefore, the general population largely remains  immunologically naïve to mpox, while the risk to health, contribution to  international spread and burden of insufficient response capacities, remains low.  Exceptions to this include where mpox is inadvertently introduced into high-risk  settings, such as newborn and infant care units. 

    The overall public health risk for all other individuals without multiple sexual partners is, therefore, assessed as low.

Overall public health risk

    Mpox continues to pose a public health risk across all WHO regions,  with the likelihood and impact varying by population group, transmission context,  and local response capacity. The African Region will most likely continue observing  sustained community transmission in several countries  outside historically endemic areas, as well as recurrent outbreaks in countries  where zoonotic transmission occurs. While all countries remain at risk of  importation and limited local transmission, recent outbreaks (starting from 2022- 2023) have confirmed observations that sustained transmission and geographic  spread are largely driven by sexual contact in specific population groups and  network dynamics, rather than in the general population, with some notable  exceptions such as health facility-based outbreaks.

    While most countries have established outbreak response mechanisms,  such as early detection and contact tracing that help in controlling  viral spread, the effectiveness of classic contact-tracing for a sexually  transmissible infection remains very limited. Other countries are less prepared and  at a higher risk of missing chains of local transmission, especially where low  index of suspicion, stigma, and discrimination create barriers to access diagnostic testing, clinical care services and implementation of infection prevention and  control measures, and where political and socio-cultural  contexts or other  circumstances preclude timely information-sharing with communities, health  sector partners and timely and complete reporting to WHO.

    While improvements in understanding mpox transmission and risk have  improved since the first mpox public health emergency of international  concern (PHEIC) was declared in 2022, important knowledge gaps remain. These  include uncertainties regarding the role of asymptomatic or pauci-symptomatic  infections, the duration and extent of immunity  following infection or vaccination  (e.g., for immunocompromised individuals), risk factors for severe disease beyond known immunocompromising conditions, and the contribution of zoonotic  spillover and potential human-to-animal transmission. Limited data regarding  animal reservoirs and transmission at the human–animal–environmental interface further limits risk characterization in endemic settings. The lack of  reporting by some countries further limits overall community awareness,  appreciation of risk, and visibility on continuing evolution of the epidemic.

    Several cases and larger outbreaks have been reported in humanitarian emergency settings such as IDP and refugee camps and other congregate,  overcrowded settings, but the risk of spread and modes of transmission in these  settings, including the role of living conditions among other factors, are still poorly  understood. Additionally, transmission between children outside of the  household setting is not fully understood, and its potential to sustain spread of the  virus in the community context has not been quantified.

    In recent years, access to diagnostics, vaccines, and response tools has  improved through coordinated efforts by WHO and partners, and 19 countries  in Africa have implemented vaccination for populations at highest risk.  However, funding constraints, competing public health priorities, and reliance on  limited resources for vaccine supply continue to challenge sustained response  efforts, particularly in low- and middle-income countries. Delays in vaccine  introduction and limited coverage reduce the potential impact of vaccination,  underscoring the importance of prioritization and timely vaccine deployment. In  addition, data on the effectiveness of available therapeutics for mpox remain  limited, particularly in settings reporting the highest burden of disease.

    The detection of a recombinant MPXV strain with genetic elements of  both clade Ib and IIb MPXV warrants continued monitoring. To date, one  additional case has been detected since the last RRA, bringing the cumulative case  count to three. The geographic areas where the recombination event first  occurred remain unknown. While the public health risk associated with this  recombinant strain is currently considered low, ongoing genomic surveillance is  essential given uncertainties related to viral evolution and recombination.

    Overall, MPXV continues to circulate in all WHO regions and pose distinct risks across different population groups and  settings. Sustained  transmission of this still emerging and evolving orthopoxvirus continues, posing  health risks for vulnerable individuals of all ages and in all settings. While  response capacity continued to improve during the second PHEIC, it remains  uneven with suboptimal reporting practices, and highly dependent on dwindling or  non-existent resources as priorities shift. Transition to longer term disease  prevention and control programmes and strategies is still in early stages in most  settings and resources remain extremely limited as interest in mpox response  wanes. Taken together, this context creates additional risk that the gains made  over the past few years may erode. 

    Thus, the overall public health risk at the global level is assessed as moderate.

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Source: 

Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment-mpox--global-v.7

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