Rapid #risk #assessment: #Diphtheria, African Region (WHO, September 17 '26, summary)

 

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Risk statement

    Diphtheria remains a public health threat in the WHO African Region. Since 1 March 2026, transmission has continued in Chad, Guinea, Mali,  Mauritania, Niger, Nigeria and South Africa, and a new outbreak has been  detected in Senegal. 

    The current situation in Algeria could not be assessed as no updated  epidemiological information for 2026 was available when this RRA was performed. 

    Most recent incidence data came in week 32/2026 (ending 9 August  2026) from Senegal, reporting 12 laboratory-confirmed diphtheria cases,  including two deaths, reported between 21 July and 10 August 2026.

    Based on the most recent information available through epidemiological  week 33 of 2026, Nigeria continues to report the largest number of cases (68%  of all cases). 

    Guinea has reported a recent increase in morbidity and mortality, with  over 100 recorded deaths and a persistently high case fatality ratio (CFR) of 15.8%. 

    Geographically extensive transmission is reported in Mauritania and Niger, as well as new cases identified in Senegal. 

    Mali has reported cases across several regions, although incidence has declined substantially. 

    In Niger, the number of cases and deaths reported, and the CFR remain  lower than during the corresponding period of 2025. 

    South Africa continues to report clusters and sporadic respiratory cases,  albeit with good contact tracing and case investigation. 

    Comparisons across countries should be interpreted cautiously because  reporting periods, case definitions and classification practices differ.

    National authorities, WHO and partners continue to implement  coordination, surveillance, laboratory testing, vaccination, case and contact  management, and risk communication and community engagement activities. However, persistent population-immunity gaps, very low laboratory confirmation  rates in most countries, delayed and incomplete reporting, uneven access to  timely treatment (antibiotics and diphtheria antitoxin (DAT)), insecurity, displacement and population movements continue to impede outbreak control.

    Assuming that no additional interventions are implemented beyond  those already in place, transmission is likely to persist, with the potential for further spread among susceptible populations and continued severe  outcomes where case detection, referral and treatment are delayed.

    The overall risk at the regional level is assessed as moderate, unchanged from RRA v2. 

    Factors sustaining the risk include:

        • Ongoing transmission in eight countries (Chad, Guinea, Mali,  Mauritania, Niger, Nigeria, Senegal, and South Africa), indicating persistent  circulation across the Region.

        • In Nigeria, the epidemic is highly geographically concentrated, with  90% of reported cases originating from Kano, Bauchi, Katsina, Borno and Sokoto States.

        • In Guinea, recent increases in cases and deaths and a persistently  high CFR potentially indicate continuing gaps in early detection, timely referral, and access to appropriate treatment.

        • Geographically extensive transmission in Mauritania and Niger, as  well as continued transmission across several regions of Mali, including in settings  affected by insecurity, displacement, population movements, and limited access to  health services.

        • Persistent gaps in primary vaccination and limited booster-dose  coverage, leaving susceptible cohorts among older children, adolescents, and  adults, particularly within displaced, mobile, and hard-to-reach populations.

        • Decline in the coverage of DTP1 (76% in 2024 to 67% in 2025) and  DTP3 (74% in 2024 to 65% in 2025) in South Africa – according to WHO/UNICEF  estimates released in July 2026.

        • Low laboratory confirmation rates, due to limited laboratory supplies,  lack of reagents, challenges with sample collection and shipment, and shortages  of trained personnel.

        • Delayed and incomplete reporting, retrospective reporting, and  inconsistent use of standard case definitions and case classification across affected  countries, which constrain timely detection and interpretation of  epidemiological trends.

        • Limited availability of diphtheria antitoxin (DAT) in national stocks,  hindering appropriate clinical care for respiratory diphtheria.

        • Limited availability of specialized trained clinical and laboratory  personnel 

        • Cross-border population movements and gaps in information  exchange, which sustain the risk of spreading between neighbouring countries.

    These concerns are moderated by established national coordination and  response mechanisms and continued technical and operational support from  WHO and partners. Incidence has declined substantially in Mali, while the number  of cases and CFR reported in Niger remain lower than during the corresponding  period of 2025. However, cases in Guinea remain higher than in the comparable  period in 2025. Declining or relatively stable trends have also been observed in  some other affected countries. 

    Surveillance, case investigation, contact management, laboratory testing,  reactive vaccination and catch-up activities continue, although their  implementation and performance vary across countries. Case-management  capacity has been strengthened and essential supplies distributed in selected  settings, while risk communication and community engagement activities remain  ongoing. 

    Although transmission persists and localized cross-border spread remains possible, despite Senegal reporting cases, available information does  not indicate widespread regional acceleration or sustained transmission in  additional countries.

    The risk at the global level is assessed as low, unchanged from RRA v2.  Reported transmission remains concentrated in affected countries in the WHO  African Region, with no documented sustained transmission beyond the Region.  Nevertheless, international spread through travel and population movements  remains possible, particularly among susceptible populations.

    Confidence in the assessment is moderate because of low laboratory  confirmation in most settings, differences in reporting periods and case definitions, retrospective reporting and reclassification, and delayed or incomplete reporting from some countries.

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Source: 

Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment---diphtheria--african-region-v.3

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West African Clade C #MERS-CoV Strains BF785 and Mor213 Induce More Robust #Interferon and Inflammatory Signaling Compared to Clade A in #Human Respiratory Cells

 

Abstract

Clade A Middle East respiratory syndrome coronavirus (MERS-CoV) spilled over from camels into humans in Saudi Arabia in 2012 and caused pneumonia and severe respiratory disease, with a 37% case fatality rate. While clade A and B viruses are closely related phylogenetically, clade B MERS-CoV strains have since outcompeted clade A strains and continue to circulate in camels and humans in the Middle East and cause outbreaks in humans. Clade C strains circulate in camels across the African continent but have not been reported to cause disease in humans. We have shown that a number of East African clade C isolates are less able to utilize the TMPRSS2-mediated pathway for viral entry in both cell lines and primary nasal epithelial cultures, which may underlie the reduced replication of East African clade C strains in humans. However, the reduced replicative capacity of West African strains in human cells appears to be independent of viral entry, suggesting an alternative basis for their attenuation. Here, we report that West African clade C MERS-CoV isolates with deletions in ORF4b encoding a key accessory protein, NS4b, induced significantly more robust interferon and inflammatory responses than clade A MERS in human respiratory cell lines and primary bronchial air–liquid interface cultures. The replication deficit for the West African strain BF785, which has a complete deletion of ORF4b, was partially rescued when RNASEL was knocked out in A549 cells. These findings demonstrate that complete loss of NS4b results in stronger innate immune activation than partial truncation and suggests that differential selection on NS4b may contribute to the varying phenotypes of clade C MERS-CoV strains circulating in African camels.

Source: 

Link: https://www.mdpi.com/1999-4915/18/9/935

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#Risk #assessment of introduction, spread, and zoonotic #spillover of #MERS-CoV Clade B in #camel populations of the Nile Basin and Across #Africa (WHO, summary)

 

INTRODUCTION  

    The Global Early Warning System for Health Threats and Emerging Risks at the Human-Animal Ecosystems Interface (GLEWS+) is a joint initiative of the Food and Agriculture Organization of the UN (FAO), the World Health Organization (WHO), and the World Organisation for Animal Health (WOAH). 

    Within this framework, the GLEWS+ Risk Assessment (RA) mechanism enables the three organizations to jointly assess emerging health threats at the human–animal–ecosystem interface and provide evidence-based risk estimates. 

    These assessments support Members and State Parties in strengthening the prevention, detection, response and control measures.  

Event Description and Scope of the Assessment 

    Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic virus for which dromedary camels (Camelus dromedarius) are recognized as the primary animal reservoir. 

    Viral circulation within camel populations poses a risk of transmission to humans, particularly in settings characterized by frequent and close human–camel interactions. 

    Historically, MERS-CoV strains detected in dromedary camels in Africa have belonged to clade C, whereas clade B viruses have been associated with the majority of reported human MERS cases and have predominantly circulated in dromedary camel populations in the Middle East. 

    The recent detection of MERS-CoV clade B genome fragments in camels from the Nile Basin region represents a notable epidemiological development, suggesting the possibility of inter-regional viral movement and genetic mixing. 

    This finding may have implications for virus circulation and transmission dynamics, including potential changes in the risk of zoonotic spillover to humans and/or alterations in viral transmissibility and pathogenicity. 

    This assessment evaluates the risk of spread of MERS-CoV clade B within camel populations at both sub-regional (Nile Basin) and regional (Africa) levels. 

    It also assesses the risk of spillover from infected camels to humans in Nile Basin countries. 

    The assessment considers available virological, epidemiological, ecological, and socio-economic factors that influence virus circulation, including camel husbandry practices, pastoralist mobility patterns, cross-border animal movements, live-animal trade networks, and the extent of human-camel contact in the region.  

    Information used in this assessment was compiled from eight countries in Africa reporting camel populations exceeding 10,000 in 2024. 

    The countries included in the assessment are:     

        ° Chad, 

        ° Egypt*, 

        ° Eritrea*, 

        ° Ethiopia*, 

        ° Kenya*, 

        ° Libya, 

        ° South Sudan* and 

        ° Sudan*. 

    The six countries belonging to the Nile Basin sub-region are indicated by an asterisk (*). 

    This risk assessment reflects information available to 27 July 2026. FAO, WHO and WOAH will review and update the assessment as new information becomes available.  

SUMMARY 

    Middle East respiratory syndrome coronavirus (MERS-CoV) is an enveloped, positive-sense RNA virus belonging to the genus Betacoronavirus. 

    It causes Middle East respiratory syndrome (MERS), a zoonotic respiratory disease first recognized in 2012, following the detection of human cases in Saudi Arabia and Jordan. 

    As of 11 June 2026, a total of 2,637 laboratory-confirmed human cases have been reported to WHO globally, the majority from countries in the Arabian Peninsula, with an estimated crude case fatality ratio (CFR) of approximately 37%. (WHO, 2025c) 

    Dromedary camels (Camelus dromedarius) are the primary animal reservoir of MERS-CoV and the main source of zoonotic transmission to humans. 

    Human infections are thought to occur through direct or indirect contact with infected camels. 

    Consumption of raw camel products is considered a plausible route of exposure, although it has not been definitively confirmed as a primary transmission pathway. 

    Human-to-human transmission can occur, particularly in healthcare settings and among those in close-contact. 

    MERS-CoV antibodies have been found in other camelid species, including Bactrian camels, hybrid camels, llamas and alpacas, indicating susceptibility to infection (Islam, 2003). 

    However, these species are not considered to play a significant role in the current epidemiology of MERS.  

    MERS-CoV has evolved into three genetic clades (A, B, and C) with distinct geographic patterns. 

    Clade B predominates in the Arabian Peninsula and has been associated with all recent human infections. 

    Clade A has not been detected since 2015 and is considered extinct. 

    Clade C circulates among dromedary camels across Africa and despite frequent camel imports from Nile Basin countries into the Arabian Peninsula, has not become established in local camel populations. 

    Experimental and phenotypic studies indicate that clade B viruses exhibit higher replication efficiency in human respiratory tissues and experimentally infected camelids, more efficient cellular entry, and prolonged viral shedding compared with clade C viruses. (Rodon, 2023) 

    These characteristics suggest a greater zoonotic potential and an increased likelihood of transmission to humans. (Zhou, 2021) 

    The global camel population is estimated at over 42 million heads as of 2023, with more than 80% of the population in Africa (FAO, 2025a). 

    Camel trade within Africa is predominantly regional and fragmented, with significant informal cross-border movement. (WHO, 2025d, FAO, 2026) In the Nile Basin and the Horn of Africa {1}. 

    Camel trade and movement are largely driven by informal cross-border pastoralist systems, with frequent but poorly documented movements between neighboring countries such as Sudan, Ethiopia, Kenya, and South Sudan. 

    Sudan plays a central role as a major camel exporter, with substantial formal and informal movements to neighboring countries and toward North Africa, while Egypt functions primarily as a terminal hub where camels from multiple origins converge for trade and slaughter. 

    In contrast, long-distance east-to-west transcontinental movement appears limited, with little evidence of sustained camel movement from the Nile Basin into North or West Africa. (Younan et al., 2016) 

    Recent genomic surveillance studies have suggested the introduction of MERS-CoV clade B strains into camel populations in the Nile Basin, outside its historically recognized circulation in the Arabian Peninsula. 

    In Egypt, phylogenetic analyses of a camel-derived sample identified genome fragments clustering with clade B viruses from the Arabian Peninsula, circulating alongside endemic African clade C viruses (Gomaa, Edwards, Wang, Taweel, et al., 2025). 

    Recombination analyses in these studies were interpreted by the authors as suggesting potential genomic mixing between introduced clade B and endemic clade C lineages, highlighting a potential for inter-regional viral exchange and the emergence of novel variants. 

    However, as the publicly available sequences are incomplete, these findings require confirmation through full genome sequencing.  

    In a separate study (Hassan et al., 2025), metagenomic sequencing of nasal swabs from camels imported from Sudan also detected MERS-CoV genome fragments clustering with clade B human and camel strains. 

    Whole genome sequencing would be necessary to confirm these findings and better characterize their evolutionary relationships. 

    Overall, while these observations suggest the possible introduction of clade B viruses into camel population in the Nile Basin sub-region, additional research is required to determine whether there is sustained circulation, establishment, or recombination of clade B viruses in continental African camel populations. 

    Using a qualitative evidence-based approach and considering the assessed likelihood and consequences in the countries assessed, the overall risk at sub-regional level (Nile Basin) of further introduction and spread of MERS-CoV clade B within camel populations is minor. 

    The risk of introduction and spread from camel populations in the Nile Basin to camel populations in neighbouring countries is also assessed as minor. 

    However, if MERS-CoV clade B is introduced and established in camel populations in the Nile Basin countries, the public health risk of spillover from camels to humans exposed to infected camels or their products is assessed as high.  

    The level of confidence in the risk estimates is considered low for the first two questions, reflecting limitations in the quality and completeness of available genomic data, the presence of plausible but unconfirmed transmission pathways, very limited surveillance in camels and humans, and evolving camel trade dynamics that may facilitate virus spread within and beyond the Nile Basin. 

    The level of confidence is considered moderate for the third question. 

    While the clinical presentation and potential consequences of MERS-CoV infection in humans are well documented and observed in previous outbreaks, important uncertainties remain regarding the social, behavioral, and contextual factors that influence the likelihood of camel- to- human spillover in the Nile Basin.  

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{1} Countries in the Horn of Africa are: Djibouti, Eritrea, Ethiopia, and Somalia

Source: 

Link: https://www.who.int/publications/m/item/risk-assessment-of-the-introduction--spread--and-zoonotic-spillover-of-mers-cov-clade-b-in-camel-populations-of-the-nile-basin-and-across-africa

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Pan-continental #spillover #risk: integrated spatiotemporal, transmissibility and #surveillance analysis of avian #influenza #H5N1 in #Africa

 

Abstract

Background: 

The HPAI H5N1 panzootic represents a critical threat to human health in Africa, where traditional poultry systems and dense human-animal interfaces facilitate frequent zoonotic spillover. While sporadic human cases raise pandemic concerns, continent-wide integration of spatial dynamics, transmissibility indicators, and surveillance performance has been lacking. This study quantifies avian influenza transmission over two decades across Africa, identifies geographical hotspots, and evaluates the responsiveness of current surveillance systems.

Methods: 

We analysed 8,037 avian influenza outbreak events and 369 laboratory-confirmed human cases, predominantly caused by HPAI H5N1 (2004–2025), using harmonised data from FAO (EMPRES-i+), WHO, and WOAH. A Bayesian Besag-York-Mollié (BYM) spatiotemporal model estimated residual transmission risks and Incidence Rate Ratios (IRR) by subtype. The basic reproduction number (R₀) was derived via an exponential growth model applied to human outbreak phases across infectious durations of 7–30 days. Surveillance responsiveness was assessed by quantifying notification delays between clinical observation and official reporting.

Results: 

Risk of infection in animals: HPAI H5N1 was the dominant strain, representing 87.8% of animal cases, with Egypt acting as the primary epidemiological epicentre (66% of total records). The spatiotemporal model revealed that H5N1 is associated with a significantly higher risk of animal infection (IRR = 8.37; 95% CI: 6.65–10.53). Although 71% of outbreaks were reported within 5 days of detection, significant delays (≥15 days) occurred in 12% of cases, with notable regional disparities. Risk of infection in human: H5N1 was associated with a 67-fold increase in the incidence of human cases compared to other subtypes (IRR = 66.78; 95% CI: 25.29–176.37). Sensitivity analyses yielded R0 estimates ranging from 1.05 (95% CI: 0.91–1.31) to 1.23 (95% CI: 0.60–2.33), indicating localised epidemic potential.

Conclusion: 

Our findings highlight a persistent and geographically heterogeneous H5N1 reservoir in Africa with high zoonotic affinity. Although sustained human-to-human transmission remains limited, the identification of dual poultry-human hotspots and localised R0 peaks underscores the urgent need for geographically targeted One Health interventions. Strengthening real-time reporting systems and improving biosecurity in high-risk poultry value chains are critical to mitigating future pandemic threats on the continent.

Source: 

Link: https://www.frontiersin.org/journals/epidemiology/articles/10.3389/fepid.2026.1813211/full

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Institutionalising public #health #emergency #preparedness and responses in #Africa: lessons learned during the 2022-2025 #outbreaks with crossborder spread potential

 

Summary

Lessons and best practices from outbreaks during 2022–25 in Africa were not comprehensively documented or shared to inform future outbreak responses. We conducted a narrative review of published articles and outbreak response reports of mpox, cholera, Ebola virus disease, and Marburg virus disease and captured experts' perspectives and lessons. We analysed and presented the data in themes. Evidence indicates that effective responses are built on routine investments maintained between outbreaks, particularly in decentralised laboratories, digital surveillance systems, community structures, and clinical trial readiness. The institutionalisation of response mechanisms through national public health institutes, incident management systems, and emergency operations centres reflects a maturing continental preparedness architecture, reinforced by rapid regional solidarity, south–south cooperation, and timely partner support. National political leadership was crucial in mobilising resources and ensuring public compliance, whereas innovations such as expanded genomic surveillance, timely deployment of investigational countermeasures, mobility-aware outbreak control, and improved early-warning systems strengthened responses to outbreaks. The successful control of these recent outbreaks highlights the importance of strengthening preparedness, institutionalising response systems, and fostering coordinated, Africa-led health security frameworks to support resilient and sustainable outbreak response.

Source: 

Link: https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(26)00160-9/fulltext

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Disentangling the drivers and host-mediated #global #spread of #H7 #influenza A virus

 

Abstract

Avian influenza H7 viruses pose a significant zoonotic and pandemic threat, yet their evolutionary dynamics, spatial transmission patterns, and host-specific roles remain underexplored. This study integrates phylodynamic and phylogeographic analyses to map global H7 dissemination, quantify host-specific contributions, and identify key ecological and anthropogenic drivers. Epidemiological data show key epidemic waves in Asia during 2013-2014 and 2016-2017, and in Africa in 2023. The Eurasian and American lineages of H7 viruses exhibit transmission with a median velocity of ~661 km/year and ~354 km/year, though spread varies significantly by virus subtype. Anseriformes (~587 km/year) and wild birds (~654 km/year) spread the Eurasian lineage of H7 viruses more rapidly and over greater distances than Galliformes and domestic birds. Geographic distance is negatively associated with the spread of the H7 virus, while temperature and poultry density show positive association. In this work, we identify Asia as an important H7 virus evolutionary epicenter. Anseriformes drives transcontinental spread, whereas Galliformes facilitates local amplification. The dynamics of the H7 virus are shaped by ecological and socioeconomic factors. A One Health approach emphasizing targeted surveillance and global cooperation is essential to mitigate cross-species transmission and future pandemic threats.

Source: 

Link: https://www.nature.com/articles/s41467-026-72718-9

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Rapid #risk #assessment, acute event of potential public health concern: #Diphtheria, #Africa Region (#WHO, March 20 '26)

{Summary)

Risk statement

-- This WHO Rapid Risk Assessment (RRA, v2) aims to assess the risk of diphtheria at the regional level, considering the public health impact, the risk of geographical spread and the risk of insufficient control capacities with available resources. 

-- Diphtheria is a major public health problem in the WHO African Region (AFR) despite significant efforts on immunization in the past decades (e.g. introduction of DTP vaccine in the Expanded Program on Immunisation in 1974). 

-- Between 2000 and 2024, 75 789 diphtheria suspected cases were reported across the Region with an average 3 500 cases per year.    

-- Between the beginning of 2025 and as of 1 March 2026, over 29 000 suspected diphtheria cases with 1 420 deaths (CFR 4.9%) have been reported across these eight countries: Algeria, Chad, Guinea, Mali, Mauritania, Niger, Nigeria and South. 

-- This represents a 67% increase in the number of suspected cases (11 749 additional cases) and a 59.4% increase in the number of deaths (529 additional deaths) reported since the last WHO RRA (v1) conducted in October 2025, Nigeria continues to account for the majority of suspected cases (62.6%) and deaths (66%) in the Region. 

-- Of the 18 130 total confirmed cases (clinically compatible, laboratory-confirmed and epidemiologically linked) across the eight affected countries, 752 (4%) cases were recorded as laboratory-confirmed: Algeria (8), Chad (1), Guinea (48), Mali (66), Mauritania (12), Niger (313), Nigeria (211) and South Africa (93).     

-- Case data trends from 2026 have been difficult to interpret, with extremely delayed case reporting from countries (both to the national and regional levels), and instances of under-reporting also being notified, particularly from humanitarian settings. 

-- However, a lower number of cases are being consistently reported than earlier in the outbreak and thus it appears that new cases continue to decline or plateau, as seen in half of the affected countries (Chad, Mali, Mauritania, and Nigeria).    

-- Since the first WHO RRA (v1) conducted in October 2025, the regional CFR remains around 5%. 

-- While Guinea continues to report among the highest CFRs in the region at 19%, South Africa’s CFR has increased since the last WHO RRA (v1) to 19%.  

-- Children aged 5–14 yrs (57%) and females (63%) are the most affected; where information is available on the vaccination status of cases, most cases are unvaccinated, under-vaccinated, or with unknown vaccination status.   

-- While the overall risk was previously assessed as “HIGH” at the regional level in October 2025, it is now considered “MODERATE” due to:  

• Overall declining trend in number of weekly cases regionally, with country-specific trends also declining in half of the affected countries (Chad, Mali, Mauritania and Nigeria), and only sporadic cases reported from South Africa. 

• Strengthened coordination of public health response through the activation of an Incident Management System (IMS) in most of the affected countries. A joint Regional Office for Africa (AFRO) and WHO headquarters (HQ) IMS structure was activated to support the regional coordination of the response, with high-level ministerial commitment to controlling the outbreaks in the affected countries.  

• Implementation of immunization activities as part of the outbreak response in most of the affected countries. 

• Strengthening of surveillance, case management, community sensitization, through capacity building activities, and the provision of diphtheria antitoxin (DAT), antibiotics, laboratory supplies, etc.  

-- Nonetheless, some challenges continue to prevent the effective containment of these outbreaks:  

• The complex humanitarian situation in many of the affected countries continues to contribute to poor access to immunization and healthcare services for internally displaced persons (IDPs), nomads, miners, and migrants. Unsanitary living conditions (in displacement camps) are also favouring the transmission of diphtheria. These increase the exposure risk of vulnerable groups (particularly women and children) to diseases.   

• Limited laboratory confirmation due to lack of reagents, sample transportation challenges and limited available of laboratory capacity.  

• In most of the affected countries, the annual coverage for routine diphtheria vaccination remains below the national targets thereby contributing to the resurgence of cases and outbreaks.  

• Global scarcity of DAT for the treatment of affected persons. 

• High internal and cross-border movements of susceptible individuals (unvaccinated or not fully vaccinated). 

• Persistent funding challenges across most affected countries exacerbated by the current challenging international funding landscape.  

-- The overall risk at the global level remains ‘’LOW’’ due to: 

- The global risk of diphtheria outbreaks from the ongoing multi-country diphtheria outbreak in the African region is assessed as low, given the existence of routine immunization programs in most countries. 

- Nonetheless, the risk posed by international travel of susceptible populations from the WHO African Region cannot be overlooked, highlighting the need to strengthen risk communication, demand generation and reactive immunisation, as well as the need for enhanced data sharing and surveillance globally. 

(...)

Source: 

Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment---diphtheria--african-region-v.2

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#Epidemiology and #genomic features of #MERS #coronavirus in #Africa: a systematic and meta-analysis review

 

Highlights

• 74% pooled MERS-CoV seroprevalence in African dromedaries

• Highest MERS-CoV RNA incidence (15.3%) observed in juvenile dromedaries

• 2.4% pooled MERS-CoV seroprevalence in camel-exposed humans

• African MERS-CoV clade C exhibits unique polymorphisms

• Clade-specific features might explain low MERS-CoV infection rates in Africa

Abstract

Objective

We explored factors contributing to the low human MERS-CoV prevalence in Africa by assessing MERS-CoV epidemiological and genomic features.

Methods

We followed the PRISMA guidelines. We searched for articles on epidemiological and virological MERS-CoV characteristics in humans and camels in Africa until August 2025. We used a generalised linear mixed-effects model to calculate pooled proportions. We identified relevant polymorphisms in African MERS-CoV lineages compared with the prototypic EMC/2012 and contemporary Arabian MERS-CoV (clade B5).

Results

We included 53 articles, with 31 used in the meta-analysis. Kenya, Egypt, and Ethiopia contributed to 66.03% of all included studies. Pooled MERS-CoV RNA positivity in African dromedaries was 6.09%, with juveniles (15.29%) having a higher incidence than adults (4.51%). The pooled MERS-CoV seroprevalence was 73.67%, with adults (80.96%) higher than juveniles (36.02%). In human-focused studies, only nine PCR-confirmed MERS cases were reported, six travel-associated and three autochthonous cases, despite a pooled seroprevalence of 2.4%. Genomic analyses identified MERS-CoV clade C-specific polymorphisms in the Spike and accessory genes with putative phenotypic impact.

Conclusion

We found the highest MERS-CoV RNA positivity in young dromedaries. Elevated MERS-CoV seroprevalence in mainly asymptomatic camel-exposed humans suggests an underestimation of MERS-CoV infections in Africa. The ongoing MERS-CoV evolution emphasises the need for active genomic surveillance to monitor signatures of human adaptation.

Source: 

Link: https://www.ijidonline.com/article/S1201-9712(26)00091-3/fulltext

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#Diphtheria - #Africa Region (#WHO, D.O.N., Nov. 21 '25)

{Excerpt}

Diphtheria is a major public health problem in the WHO African Region despite substantial efforts on immunization activities over the past three decades. 

Between 2000 and 2024, 75 789 suspected diphtheria cases were reported in the Region, with the majority reported from 2023 to 2024, when Algeria, Chad, Gabon, Guinea, Mali, Mauritania, Nigeria, Niger, and South Africa reported a resurgence of diphtheria outbreaks with approximately 57 000 suspected cases and 2 000 deaths (case fatality ratio (CFR) of 3.5%) recorded. 

The countries most affected were Guinea, Nigeria and Niger. 

Most cases reported were in children under fifteen years and female. 

Over 50% of suspected cases were non-vaccinated or with unknown vaccination status. 

In 2025, as of 19 October 2025, over 17 000 suspected diphtheria cases and about 900 deaths with an average CFR of 5.1% have been reported across eight Member States in the African Region; Algeria, Chad, Guinea, Mali, Mauritania, Niger, Nigeria, and South Africa.

Of these suspected cases, 7 886 were confirmed through laboratory testing, epidemiological linkage, or clinical compatibility. 

Laboratory-confirmation has been conducted in 6.8% (n=1181) of the suspected cases. 

Women, children aged between 5 and 18 years and young adults less than 30 are the most affected groups. 

The situation seems to have worsened in Mali, Mauritania and Niger in recent weeks with increasing trends and geographic expansion of the outbreaks reported in these countries. 

In addition, high CFRs (up to 24%) have been reported across all affected countries.   

The overall public health risk posed by the diphtheria event in the African Region is classified as ‘’high’’ due to:

-- Significant risks of further widescale spread:

- The humanitarian profile of some of the affected countries (Chad, Mali, Niger, Nigeria): fragile, conflict-affected and vulnerable settings, with low vaccination coverage often recorded among displaced populations.

- Outbreak hotspots are sometimes located in hard-to-reach areas with security constraints. 

- Crowded, unsanitary living conditions in displacement camps in humanitarian settings.

- Low routine immunization coverage in most affected countries and important heterogeneity in coverage at subnational level in a number of countries - with pockets of under-vaccination leading to outbreaks (e.g. Nigeria, Chad etc.).

- Disruptions caused by the COVID-19 pandemic, causing significant drop of vaccination coverage between the first and the third dose across all affected countries. Although in response to declining immunization coverage, global partners launched The Big Catch-up, a coordinated effort to restore and strengthen immunization services and close immunity gaps, especially for vaccine-preventable diseases such as diphtheria.

- Weak health system capacity in most affected countries (shortage of health professionals, low clinical management capacity, etc.). 

- Shortage of laboratory supplies reported by most affected countries, leading to delays in case reporting and laboratory confirmation. 

- Global shortage of diphtheria anti-toxin (DAT) necessary for the treatment of affected persons. 

- High case fatality ratio observed in many of the affected countries.

- High internal and cross-border movements of susceptible individuals (unvaccinated or not fully vaccinated). 

- Insufficient resources to control the outbreaks across most affected countries.

The overall public health risk posed by the diphtheria event at the global level is classified as ‘’low’’ due to:

-- The global risk of diphtheria outbreaks from the ongoing multi-country diphtheria outbreak in the African Region is assessed as low, given the existence of routine immunization programs in most countries. 

- Nonetheless, the risk posed by international travel of susceptible populations from the African Region cannot be overlooked, highlighting the need to strengthen risk communication and surveillance globally. 

(...)

Source: 

Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment---diphtheria--african-region-v.1

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#Mpox in #Africa: What we know and what is still lacking

Abstract

Emerging as a major global health threat, Mpox previously known as Monkeypox has drawn attention due to a worrying surge in cases. This zoonotic disease, native to Central and West Africa, is marked by fever, rash, and lymphadenopathy and is primarily spread through direct contact with infected animals or people and indirectly through contaminated objects. Recent studies have indicated possible sexual transmission, underscoring how human behavior and environmental changes are increasing its prevalence, even though human-to-human transmission is less efficient than that of smallpox. Mpox is endemic in several African countries, and currently, the infection has spread in non-endemic countries, including Rwanda, Uganda, and Kenya. Democratic Republic of Congo is the epicenter of the current Mpox outbreak. From January 1, 2022, to August 6, 2024, sixteen African countries reported Mpox outbreak. Several factors, including population immunity deficiencies and changes to the environment and ecology, have led to the widespread of Mpox in Africa. Challenges such as the fragile healthcare system, limited vaccine availability and access, weak surveillance, and low public awareness poses difficulty in containing the infection in affected countries. Given the potential of Mpox to disrupt several sectors including health systems, which may ultimately reverse progress in achieving the sustainable development goals by 2030. It is imperative for countries, both within and outside Africa, to extend financial aid and human resources to combat the infection effectively.

Source: PLoS Neglected Tropical Diseases, https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0013148

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#Seroprevalence of #H9N2 and #H5 avian #influenza in mixed-species #poultry #farms in Northern #Benin

ABSTRACT

Avian influenza is one of the major threats to poultry and human health in northern Benin, while mixed-species farming systems increase the risks of viral transmission. The present study estimated the seroprevalence of avian influenza subtypes H9N2 and H5 in indigenous chickens and guinea fowls in the Atacora and Donga regions. A total of 300 birds including 191 indigenous chickens and 109 guinea fowls, from six districts were sampled through a cross-sectional survey using systematic random sampling. Hemagglutination inhibition assay was used to detect antibodies, revealing an overall H9N2 seroprevalence of 41%, with 17.5% of samples testing positive for H5. The seroprevalence of H9N2 was notably higher in guinea fowls (51.81% in Atacora and 52% in Donga) compared to chickens (34.95% in Atacora and 34.83% in Donga). H5 antibodies were found only in guinea fowls in Atacora (46.66%). The study also found that farms with both chickens and guinea fowls had a significantly higher odds ratio for H9N2 positivity (OR = 4.25, p < 0.001) compared to chicken-only farms. The results underscore the importance of mixed-species systems in the transmission of avian influenza, suggesting that targeted surveillance and biosecurity measures are essential for controlling the spread of these viruses.

Source: Journal of Immunoassay and Immunochemistry, https://www.tandfonline.com/doi/full/10.1080/15321819.2025.2496480

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Evolving #Epidemiology of #Mpox in #Africa in 2024

Abstract

Background

For decades after the identification of mpox in humans in the Democratic Republic of Congo (DRC) in 1970, the disease was largely confined to the rural areas of Central and West Africa and thus did not garner broad attention. On August 13, 2024, mpox was declared a Public Health Emergency of Continental Security (PHECS) by the Africa Centers for Disease Control and Prevention (Africa CDC), a notice that was followed the next day by a declaration of a Public Health Emergency of International Concern (PHEIC) by the World Health Organization.

Methods

In this study we analyzed all mpox cases and deaths, based on clinical or laboratory diagnosis, that were reported to the Africa CDC from January 1, 2022, to October 30, 2024, to identify temporal variations, geographic distributions, and epidemiologic trends.

Results

From January 1, 2022, to August 18, 2024, a total of 45,652 mpox cases were clinically diagnosed and laboratory-confirmed in 12 African countries. These cases resulted in 1492 deaths (case fatality rate, 3.3%). From 2022 to 2024, weekly laboratory-confirmed mpox cases increased by a factor of 2.8 (from 176 to 489 cases), whereas all weekly reported cases (including those with a clinical diagnosis) increased by a factor of 4.3 (from 669 to 2900 cases). The DRC, which had reported approximately 88% of mpox cases in Africa in 2024, had 19,513 cases before the emergency declaration, with a case fatality rate of 3.1% — a weekly average of 591 cases as compared with 281 in 2023. In 2024, six African countries reported their first imported mpox infections, with Burundi also reporting local transmission.

Conclusions

The high mpox disease burden in Africa, especially in the DRC — with a rising number of cases, high case fatality rate, and high degree of spread to other previously mpox-free African countries — is cause for increased international concern. Case detection, contact tracing, public health measures, and affordable vaccines are needed to implement interventions in the DRC to reduce the risk of global spread of the virus.

Source: New England Journal of Medicine, https://www.nejm.org/doi/full/10.1056/NEJMoa2411368?query=TOC

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Low-Level #Zoonotic #Transmission of Clade C #MERS-CoV in #Africa: Insights from Scoping Review and Cohort Studies in #Hospital and Community Settings

Abstract

Human outbreaks of Middle East respiratory syndrome coronavirus (MERS-CoV) are more common in Middle Eastern and Asian human populations, associated with clades A and B. In Africa, where clade C is dominant in camels, human cases are minimal. We reviewed 16 studies (n = 6198) published across seven African countries between 2012 and 2024 to assess human MERS-CoV cases. We also analyzed data from four cohort studies conducted in camel-keeping communities between 2018 and 2024 involving camel keepers, camel slaughterhouse workers, and hospital patients with acute respiratory illness (ARI). The analysis showed a pooled MERS-CoV prevalence of 2.4% (IQR: 0.6, 11.4) from 16 publications and 1.14% from 4 cohort studies (n = 2353). Symptomatic cases were rarely reported, with most individuals reporting camel contact, and only 12% had travel history to the Middle East. There was one travel-associated reported death, resulting in a mortality rate of 0.013%. The findings suggest a low camel-to-human transmission of clade C MERS-CoV in Africa. Ongoing research focuses on genomic comparisons between clade C and the more virulent clades A and B, alongside the surveillance of viral evolution. This study highlights the need for continuous monitoring but indicates that MERS-CoV clade C currently poses a minimal public health threat in Africa.

Source: Viruses, https://www.mdpi.com/1999-4915/17/1/125

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