#Incubation and infectious period, asymptomatic or presymptomatic #transmission and transmission route in #human-to-human spread of #hantavirus #infection (UKHSA, summary)

 

{Summary)

Main messages 

    1. This systematic evidence summary (search up 1 May 2026) identified and summarised evidence relating to the incubation and infectious period, asymptomatic or presymptomatic transmission and transmission route in human-to-human transmission of hantavirus infection.  

    2. Human-to-human transmission was only reported for Andes virus.  

    3. Seventeen studies were identified to include (1 to 17). All studies were from South America (Argentina, Chile, Paraguay or Uruguay) from 1995 to 2024. Three sets of studies clearly reported on the same outbreak.  

    4. Seven studies reported the incubation period, or enough information to calculate the incubation period of Andes virus (4, 6, 8, 10, 12, 13, 15, 17). Four of these reported overlapping evidence, (4, 8, 12, 17) leaving 5 independent reports. The reported incubation period ranged from 9 to 40 days, with studies reporting a mean between 21.6 to 27.5 days.   

    5. Three studies reporting incubation period included children (6, 10, 12). When evidence for children was separated, the range was 14 to 26 days. The mean (and standard deviation, SD) from one study with data to calculate it was 19.8 days (3.7) in children and 21.9 days (7.4) in adults (12). The available evidence was insufficient to determine if there was a significant difference between adults and children and not all studies separated the results.   

    6. Twelve studies reported the serial interval or enough information to calculate the serial interval of Andes virus (1, 2, 5, 9 to 14, 16, 17). Four of these reported overlapping evidence,(10, 11, 14, 17) leaving 10 independent reports. The reported serial interval ranged from 4 to 40 days with means across studies from 19.6 to 25.7 days.  

    7. Six studies reporting serial interval included children (2, 5, 9, 10, 12, 16). When evidence for children was separated, the range was 16 to 29 days. The mean (and SD) from one study with data to calculate it was 19.7 (3.5) in children and 19.5 (8.1) in adults. The available evidence was insufficient to determine if there was a significant difference between adults and children and not all studies separated the results.  

    8. None of the studies reported confirmed route of transmission. Some hypothesised routes from exposures including the possibility of respiratory, direct contact via breastfeeding, other direct contact and sexual transmission. None ruled out respiratory or fomite transmission alongside other possible routes.  

    9. No studies reported evidence of asymptomatic or presymptomatic transmission. 

    10. Most studies included groups identified as being at risk of health inequalities, including children, pregnant women, people living in rural settings and people in occupations at higher risk of exposure such as agricultural workers or farmers and people working in healthcare settings. However, none of the studies provided a comparison between groups and it was not possible to determine if outcomes differed in these groups. 

    11. Critical appraisal was not performed, which restricts the interpretation of the findings, but important limitations have been highlighted. There were a limited number of cases with likely human-to-human transmission which limits the generalisability of the evidence. Many studies also highlighted the possibility than some of these cases also had environmental exposure, although human-to-human transmission was most likely. All studies rely on selfreport of exposure and symptom onset dates, which may be subject to recall bias or misreporting. There was also discrepancy between some studies reporting on the same cases, which highlights the likelihood of misreporting of this evidence.  

    12. In summary, there was evidence from a limited number of cases to provide information of the incubation period and serial interval for human-to-human transmission of Andes virus. There was no information available that directly informed the infectious period in humans. Evidence suggested incubation period could range from 9 to 40 days, with studies reporting a mean between 21.6 to 27.5 days. The reported serial interval ranged from 4 to 40 days with means from 19.6 to 25.7 days. Although no studies were able to confirm route of transmission, some proposed routes through exposures, including the possibility of direct contact via breast-feeding, and sexual transmission or contact. No studies reported evidence of asymptomatic or presymptomatic transmission. All of the evidence is at risk of bias from misreport or recall bias, possible environmental exposure and ability to generalise due to small numbers of cases. 

(...)

Source: 

Link: https://www.gov.uk/government/publications/hantavirus-human-to-human-infection-transmission-parameters

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#HK PRC SAR, CHP investigates a #human case of #influenza #H9 #infection (June 12 '26)

 

    The Centre for Health Protection (CHP) of the Department of Health (DH) is today (June 12) investigating a case of human infection with influenza A (H9) in collaboration with relevant departments. 

    The patient is a two-year-old boy. His condition has remained mild and he is currently in stable condition. 

    The CHP will send a letter to all doctors in Hong Kong to update them on the latest developments regarding avian influenza A and to urge them to remain vigilant and report any suspected cases.

 

Case information

    The boy lives in Sha Tin District. He developed a fever and mild diarrhoea on June 9. On the following day (June 10), he was brought to Prince of Wales Hospital and was admitted for treatment. His clinical specimen tested positive for the influenza A (H9) virus by the Public Health Laboratory Services Branch (PHLSB) of the CHP. The subtyping result is pending. His clinical diagnosis was novel influenza. He is currently in stable condition and has been admitted to an isolation ward at Princess Margaret Hospital for treatment.

      The CHP's preliminary investigation revealed that the patient had no travel history during the incubation period. 

    The case has been classified as a locally acquired case. 

    The patient does not attend school or receive daycare services. 

    He is primarily cared for by his family members and spends most of his time at home or nearby. 

    His household does not keep poultry. 

    According to information provided by his family members, he has neither consumed undercooked poultry nor come into contact with any patients. 

    In early June, one of his family members took him to Wo Che Market on two occasions. During these visits, the patient stayed at a fresh provision shop in the market that sells live chickens to watch the poultry and touched the surroundings of the fresh provision shop. 

    The CHP conducted an investigation with the Food and Environmental Hygiene Department (FEHD) and collected environmental samples from the shop concerned. 

    The shop staff remained asymptomatic. 

    The patient has six household contacts and they remain asymptomatic so far. 

    The CHP has provided them with preventive medication and put them under medical surveillance.

      The CHP is continuing to investigate the source of infection of the case and is conducting whole genome sequencing of the virus sample. The CHP will also report the case to the World Health Organization (WHO).

      Humans are primarily infected with the influenza A virus through direct contact with infected poultry or through indirect contact with environments contaminated by their droppings. 

    The CHP's epidemiological investigation indicated that the patient had visited a location where live poultry was sold. It cannot be ruled out that the patient was infected through indirect contact with a contaminated environment at the wet market. 

    As young children have weaker immune systems and are incapable of maintaining good hand hygiene, the CHP advised parents to avoid taking young children to places where live poultry is sold. 

    Transporting poultry may contaminate the ground and the surrounding environment. 

    As young children are shorter in height and easy to be in contact with the surrounding environment, they are at greater risk of coming into contact with poultry droppings or contaminated areas.

      In the past ten years, the WHO has received reports of a total of over 160 cases of human infection with influenza A (H9) worldwide. 

    To date, most case of human infection with influenza A (H9) have presented with only mild clinical illness. 

    According to the WHO's risk assessment, the influenza A (H9) virus has not acquired the ability for sustained human-to-human transmissions.

 

Government's comprehensive follow-up actions

    Novel influenza A infection, including influenza A (H9), is a notifiable infectious disease in Hong Kong. 

    Compared to other highly pathogenic avian influenza strains such as H5N1 and H7N9, influenza A (H9) is a low-pathogenic avian influenza strain that causes milder illness. 

    Excluding the aforementioned case, 10 cases of influenza A (H9N2) have been reported since 1999, including four locally acquired cases and six imported cases. 

    No deaths have been recorded so far. 

    In response to the latest local case, the CHP will issue a letter to all doctors in Hong Kong, reminding them of the latest situation of influenza A (H9), and urging them to remain vigilant and report any suspected cases.

      Sporadic cases of human infection with avian influenza occur from time to time internationally. Although the current risk of an outbreak is low, the Hong Kong Special Administrative Region Government has consistently implemented preventive measures, including a disease surveillance system, the implementation of livestock control measures at farms, markets and ports, in order to prevent avian influenza.

      The PHLSB of the CHP comprises laboratories with high biosafety standards, capable of conducting, testing for high-risk pathogens, and which also possess sufficient testing and genetic analysis capabilities and facilities. Hong Kong currently has sufficient reserve of antiviral medications.

 

Preventive measures to be taken by the public

    Humans are primarily infected with the avian influenza A virus through contact with infected birds, poultry or other animals (whether alive or dead), or through surfaces or environments contaminated with saliva, mucous and animal faeces (such as wet markets and live poultry markets). 

    The virus has very low transmissibility among humans. People who have close contact with live poultry are more susceptible to contracting avian influenza. The elderly, children and people with chronic illnesses have a higher risk of developing complications such as bronchitis and pneumonia, if infected. 

    Members of the public should remain vigilant and take the following measures to prevent avian influenza:

         ° Avoid contact with poultry, birds or their droppings. If contact has been made, thoroughly wash hands with soap and water;

        ° Poultry and eggs should be thoroughly cooked before eating;

        ° Perform hand hygiene at all times, especially before touching the mouth, nose or eyes; after contact with animals or their living environments; after touching public installations such as handrails or doorknobs; or when hands are contaminated with respiratory secretions, such as after coughing or sneezing;

        ° Cover the mouth and nose with tissue paper when sneezing or coughing. Dispose of soiled tissues into a lidded rubbish bin, then wash hands thoroughly;

        ° When having respiratory symptoms, wear a surgical mask, do not go to work or school, avoid crowded places and seek medical advice promptly;

        ° Avoid crowded public places or areas with poorly ventilated; high-risk individuals may consider putting on a surgical mask when staying in such places; and

        ° Travellers returning to Hong Kong from areas affected by avian influenza outbreaks should consult doctors promptly if they have flu-like symptoms, and inform the doctor of the recent travel history and wear a surgical mask to help prevent spreading of the disease.

    The public may visit the CHP's webpages for more information: Avian Influenza Webpage, Avian Influenza Report, Avian influenza statistics and affected areas around the world, Facebook page and Youtube channel. 

 

Ends/Friday, June 12, 2026 | Issued at HKT 22:19 | NNNN

Source: 

Link: https://www.info.gov.hk/gia/general/202606/12/P2026061200852.htm?fontSize=1

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Twenty-one #countries launch coordinated #Andes virus #research initiative following #hantavirus #outbreak (WHO, June 12 '26)

 

    Following the recent Andes virus (ANDV) outbreak linked to the MV Hondius cruise ship, a globally coordinated outbreak research initiative involving investigators and institutions across 21 countries has begun implementation,  demonstrating how international research preparedness systems can be rapidly activated during health emergencies.

    The initiative, known as NAVIS, is a natural history study designed to improve understanding of ANDV transmission dynamics, incubation periods, immune responses, viral kinetics, and determinants of severe disease through harmonized longitudinal follow-up of exposed individuals.

    The study will use a harmonized prospective protocol, which was developed by Hospital Germans Trias i Pujol, Badalona, Spain, for immediate deployment after an emergency scientific consultation coordinated through the UK Health Security Agency (UKHSA)-led Hantavirus Collaborative Open Research Consortium (CORC) mobilized more than 1600 experts from over 130 countries to identify urgent scientific priorities and coordinate international research activities.

    “Closing gaps in our scientific knowledge is key to the development of medical countermeasures, and through international coordination we ensure this is accelerated. Preparedness, therefore, must include the ability to rapidly generate scientific evidence during outbreaks, not only respond to them,” said Yper Hall of the UKHSA.

    By using standardized approaches across countries, NAVIS aims to generate comparable datasets to better understand the pathogen and inform the development of medical countermeasures like tests, treatments and vaccines.

    Coordination of the NAVIS platform is being supported by ANRS Emerging Infectious Diseases (ANRS-MIE) under BE READY, a EU-funded global initiative to strengthen research preparedness and rapid scientific mobilization for future epidemics and pandemics. The study will use ISARIC (International Severe Acute Respiratory and Emerging Infection Consortium), an adaptable research framework designed to enable rapid, standardized data and sample collection during emerging infectious disease outbreaks.

    Participating countries include: 

    ° Australia, 

    ° Belgium, 

    ° Canada, 

    ° Democratic Republic of the Congo, 

    ° Denmark, 

    ° France, 

    ° Germany, 

    ° Greece, 

    ° Ireland, 

    ° Italy, 

    ° Japan, 

    ° the Netherlands, 

    ° New Zealand, 

    ° Singapore, 

    ° South Africa, 

    ° Spain, 

    ° Switzerland, 

    ° Türkiye, 

    ° the United Kingdom and 

    ° the United States.

    Participating institutions include leading infectious disease, clinical research, and public health centres such as the Australian Centre for Disease Control, Sinai Health System, Institut National de la Recherche Médicale (Inserm), Hellenic Pasteur Institute, University College Dublin, National Centre for Infectious Diseases, University Hospital Zurich, University of Liverpool, and Emory University, among others.

    “The rapid launch of NAVIS across 21 countries shows what is possible when research networks are established before outbreaks occur,” commented Yazdan Yazdanpanah of ANRS-MIE.

    NAVIS represents a practical example of outbreak research preparedness under the World Health Organization’s R&D Blueprint, which establishes research networks for pathogen families, to support rapid scientific coordination and implementation of outbreak research before emergencies emerge.

    Outbreaks such as that of the ANDV present rare opportunities for scientific investigation, with a limited window of time for generating robust evidence. Without rapid coordination and harmonized protocols, opportunities to better understand the pathogen can be lost.

    “Scientific evidence generation during outbreaks must become operational, coordinated, and immediately deployable. Future outbreak responses should begin by activating research systems that already exist rather than trying to build them during crises,” said Sylvie Briand, Chief Scientist at WHO.

    The initiative also highlights the importance of geographically-distributed research preparedness. Countries and regions where outbreaks emerge or pathogens circulate must be central participants in evidence generation through strengthened clinical trial networks, national ethics committees, laboratory systems, surveillance platforms, and outbreak research infrastructure.

    The ANDV outbreak demonstrated the importance of research preparedness. Future outbreak responses should no longer begin by building research systems during crises. They should begin by activating systems that already exist.

Source: 

Link: https://www.who.int/news/item/12-06-2026-twenty-one-countries-launch-coordinated-andes-virus-research-initiative-following-hantavirus-outbreak

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#USA, #Wastewater Data for Avian #Influenza #H5 (CDC, June 12 '26)

 

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(...)

Time Period: May 31, 2026 - June 06, 2026

    -- A(H5) Detection: 3 site(s) (0.7%)

    -- No Detection: 440 site(s) (99.3%)

    -- No samples: 52 site(s)

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(...)

Source: 

Link: https://www.cdc.gov/wastewater/emerging-viruses/h5.html?

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#Surveillance of West Nile Virus #WNV #infections in #human in #Europe, Weekly Report (ECDC, June 12 '26)

 

Week 24, 2026

Produced on 11 June 2026 at 08:15 based on data submitted up to 10 June 2026

Epidemiological summary

    Since the beginning of 2026, and as of 10 June, 1 country in Europe reported 1 human case of West Nile virus infection: North Macedonia.

    The current report in Table 1 includes the number of probable and confirmed cases of WNV infections per NUTS3 region. However, these figures are preliminary and should be interpreted with caution as they may be revised by the countries as more information becomes available. Consequently, no totals are provided. For further details on case numbers, please refer to the joint monthly report, which offers a more detailed analysis.

    Please note: The table and map in this report contain countries and areas where human West Nile virus infection cases were reported to EpiPulse Cases.

Introduction

    The European Centre for Disease Prevention and Control (ECDC) provides a weekly overview of human cases of West Nile virus (WNV) infection to support the competent authorities responsible for blood safety. This overview can aid decisions on the deferral or testing of blood donors who may have been exposed to the virus, in accordance with Commission Directives 2004/33/EC and 2014/110/EU.

    West Nile virus infection in humans is a notifiable disease at the EU level and cases are reported in accordance with the EU case definition. The table and map in this report show the countries and areas where human cases of WNV infection have been reported to the European surveillance portal for infectious diseases (EpiPulse Cases).

    More information on the occurrence of WNV infection among humans in Europe, as well as WNV outbreaks among equids and birds, is available in the joint monthly report produced by ECDC and the European Food Safety Authority (EFSA).

    Here we present the weekly report as of 10 June 2026.

Overview of West Nile virus cases in EU/EEA and EU-neighbouring countries

{Country - Affected Region - Probable - Confirmed - Total Cases}

    ° North Macedonia - Vardarski - 0 - 1 - 1

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Source: 

Link: https://wnv-weekly.ecdc.europa.eu/

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A neutralizing #nanobody targeting a conserved lateral patch on HA1 confers #protection against multiple #H7 avian #influenza viruses

 

ABSTRACT

Human infections with H7 avian influenza viruses (AIVs) have been documented globally, involving multiple subtypes and geographic regions. However, effective therapeutics targeting H7 influenza viruses remain limited. Here, a panel of nanobodies targeting the HA1 domain of hemagglutinin (HA) was identified by yeast two-hybrid (Y2H) screening, and six candidates were subsequently validated to exhibit hemagglutination inhibition (HI) activity. Of these, a subset also displayed virus microneutralization (MN) activity, while all showed binding activity in ELISA assays. Among them, Nb74 exhibited inhibitory activity against four Chinese recombinant vaccine-matched strains (Rv1–Rv4), which were generated based on the HA sequences of the corresponding inactivated vaccine strains H7-Re1 to H7-Re4. The HI-IC50 values were 0.23, 0.57, 3.65, and 43.75 µg/mL, respectively, and the MN-IC50 values for Rv1–Rv3 were 0.02, 0.06, and 1.09 µg/mL. It also retained activity against diverse clinical isolates although HI potency varied among strains. In mouse challenge experiments, intratracheal administration of Nb74 conferred robust protection, achieving 100% and 80% survival against Rv1 and Rv2, respectively, when administered prophylactically (2 mg/kg) or therapeutically (4 mg/kg). Treated mice showed accelerated body weight recovery, reduced lung viral load, and alleviated pulmonary pathology. Mechanistic analyses indicated that Nb74 neutralizes virus by blocking viral attachment to the host. Furthermore, combined hydrogen-deuterium exchange mass spectrometry (HDX-MS) with escape mutant analysis mapped its epitope to a conserved lateral patch on the HA1 subunit, consistent with a conformational epitope. Overall, these results demonstrate the therapeutic promise of intratracheally delivered Nb74 and provide insights for H7 AIVs vaccine design.

Source: 

Link: https://journals.asm.org/doi/10.1128/jvi.00563-26

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Immunogenicity and safety of AS03-adjuvanted A/Astrakhan/3212/2020 #H5N8 -like #influenza #vaccine in adults: Phase 1/2, observer-blinded, randomized trial

 

ABSTRACT

Influenza pandemics arise from novel influenza A viruses. Recent emergence of a new clade (2.3.4.4.b) of the highly pathogenic H5N1 in animals and humans highlighted its pandemic potential. We evaluated the immunogenicity and safety of GSK’s AS03-adjuvanted H5N8 vaccine in adults. In this phase 1/2, observer-blinded, age-stratified, randomized trial, healthy US adults (age, ≥18 y) received two intramuscular doses of hemagglutinin antigen (3.75 or 7.50 μg) with AS03A or AS03B, administered 21 d apart. Immunogenicity – seroprotection rates (SPRs), seropositivity, geometric mean titers (GMTs), geometric mean fold rise (GMFR), and seroconversion rates (SCRs) – was evaluated on day 43 using hemagglutination inhibition (HI) and microneutralization (MN) assays. Safety was monitored throughout the study. Of 520 enrolled participants, 518 were vaccinated. On day 43, the US Food and Drug Administration’s (FDA) Center for Biologics Evaluation and Research criteria for influenza vaccines were met. HI SPRs, seropositivity rates, SCRs, GMTs, and GMFR appeared to be higher in the AS03A vs AS03B group. Immune responses were generally higher in younger (aged 18–64 y) vs older (aged ≥65 y) adults. Immune responses were also detected in MN assays, with a correlation between HI and MN responses on day 43 across age groups and vaccine formulations. Safety was acceptable, with no increase in adverse events post-dose 2. Reactogenicity appeared more common in younger adults. The antigen-sparing potential of AS03 was demonstrated, with an acceptable safety profile. The benefit/risk profile was favorable for all formulations tested, including 3.75 µg AS03A (licensed in the US).

ClinicalTrials.gov registration: NCT05975840.

Source: 

Link: https://www.tandfonline.com/doi/full/10.1080/21645515.2026.2649314

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#Germany - #Influenza A #H5N1 viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

 

A flock of backyard laying hens in Bayern Region.

Source: 

Link: https://wahis.woah.org/#/in-review/7616

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#Risk of #Bundibugyo virus #transmission through #substances of #human origin in the #EU / EEA (ECDC, June 11 '26)

 

    11 June 2026

    The outbreak of Ebola disease caused by Bundibugyo virus (BDBV, Orthoebolavirus bundibugyoense), currently affecting the Democratic Republic of the Congo (DRC) and Uganda, draws attention to the potential risk of BDBV transmission via donated blood and blood components, cells, tissues and organs – i.e. substances of human origin (SoHO).

Background

    Ebola disease is caused by viruses in the Orthoebolavirus genus. Three orthoebolaviruses are known to cause large outbreaks: BDBV, Ebola virus (EBOV, previously known as Zaire ebolavirus), and Sudan virus (SUDV). 

    The typical incubation period for Ebola disease ranges from two to 21 days (mean: six days). 

    The prodromal phase lasts for up to 10 days, during which the infected individual experiences a sudden onset of flu-like illness. This is followed by progressive weakness, anorexia, diarrhoea, nausea, and vomiting. The next stage of the disease is characterised by gastrointestinal, neurological, vascular, cutaneous and respiratory symptoms. Haemorrhagic manifestations may also occur. During the final stage, patients may die from a combination of multi-organ failure and hypovolemic shock due to severe fluid loss. 

Key findings and recommendations

Risk assessment

    The overall risk of Bundibugyo virus transmission through substances of human origin (SoHO) in the European Union/European Economic Area (EU/EEA) is currently assessed as very low.

Recommendations

    ECDC recommends temporary deferral of asymptomatic individuals donating SoHO for at least six weeks after arriving from areas with Bundibugyo virus community transmission.

    In the context of the current Ebola disease outbreak, individuals who are being monitored due to contact with a patient with an infection, or other exposure to Bundibugyo virus are ineligible to donate SoHO for at least six weeks from the beginning of the monitoring period

    ECDC recommends a permanent deferral from donation of blood, cells and tissues for donors who have recovered from Ebola disease.

    ECDC recommends that individuals who have had sexual contact with persons who have recovered from Ebola disease should be deferred from donating SoHO for at least six weeks after exposure, irrespective of the time elapsed since the recovery of the convalescent sexual contact.

Source: 

Link: https://www.ecdc.europa.eu/en/publications-data/risk-bundibugyo-virus-transmission-through-substances-human-origin-european

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#Andes #hantavirus #outbreak in cruise ship (ECDC, June 11 '26): 1 case reclassified from probable to confirmed

 

    This page is updated as more information becomes available. It was last updated 11 June at 13:05.

    On 2 May 2026, ECDC was notified of a cluster of severe respiratory illness on MV Hondius, a Dutch-flagged cruise ship with passengers and crew from 23 countries, including nine EU/EEA countries. 

    The virus has been identified as Andes hantavirus.

    As of 11 June 2026, 13 cases have been reported in total, including 12 confirmed and one probable case.

    Since the last update on 26 May 2026, one of the previously reported probable cases was reclassified as confirmed following positive laboratory result for hantavirus infection.

    The identification of additional cases after former passengers and crew returned to their home country is possible given the long incubation period of Andes hantavirus and the possibility that some infections occurred on board on the ship. 

    The risk to the EU/EEA general population remains very low.

    ° Confirmed cases: 12

    ° Probable cases: 1

    ° Suspected cases: 0

    ° Number of deaths: 3

(...)

Source: 

Link: https://www.ecdc.europa.eu/en/infectious-disease-topics/hantavirus-infection/surveillance-and-updates/andes-hantavirus-outbreak

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Seasonal #influenza versus #COVID19 #hospitalisation #risk during the 2025–26 influenza season

 

{Excerpt}

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Contemporary surveillance data have shown higher population rates of influenza infections and hospitalisations during the 2025–26 influenza season; however, these aggregate metrics cannot disentangle infection frequency from disease severity. This analysis extends that evidence by comparing outcomes on a per-infection basis among patients with multiplex-based, laboratory-confirmed infection, showing that seasonal influenza was associated with a 43% higher risk of hospitalisation than COVID-19, corresponding to approximately 48 additional hospitalisations per 1000 infected individuals. The higher severity associated with seasonal influenza during this season likely reflects a combination of factors, including the increased virulence of circulating influenza strains, mismatch between vaccine composition and dominant circulating influenza variants, and the continued attenuation of SARS-CoV-2 severity over successive waves.

(...)

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(26)00289-6/fulltext?rss=yes

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#Neurological Manifestations in Adult #Survivors of #Ebola Virus Disease

 

Key Points

    ° Question: 

        - What neurological symptoms are present in adult survivors of Ebola virus disease (EVD) and how long are they present after infection?

    ° Findings:  

        - In this cohort study conducted in Liberia including 148 EVD survivors and 81 control individuals, survivors had a wide range of neurological symptoms during acute EVD (including headaches, altered mental status, and meningitis symptoms) and numerous neurological sequelae in convalescence (including headaches, memory loss, and neurological examination abnormalities). Seven years later, most survivors’ symptoms and findings had improved, but many still had neurological symptoms, most notably memory loss.

    ° Meaning:  

        - The findings indicate that many neurological symptoms, including those that can affect quality of life and socioeconomic burden, were associated with EVD, warranting close neurological follow-up of EVD survivors.

Abstract

Importance  

    Ebola virus disease (EVD) causes multiorgan damage and is highly fatal. EVD’s neurological impact among survivors remains poorly characterized due to limited neurological assessment capabilities in the remote regions where most outbreaks occur.

Objective  

    To characterize neurological sequelae in EVD survivors over more than 7 years’ longitudinal follow-up.

Design, Setting, and Participants  

    Under the Ebola Natural History Study (PREVAIL III; PIII), the Neurology Study of PIII was a prospective longitudinal cohort study in Liberia of adult Ebola survivors and control individuals conducted from September 2015 to March 2023 at the Partnership for Research on Vaccines and Infectious Diseases in Liberia (PREVAIL) site at John F. Kennedy Medical Center in Monrovia, Liberia. Data were analyzed from April 2023 to September 2025.

Exposures  

    Neurological evaluations were performed by trained neurologists biannually. Questionnaire and neurological examination data were collected on case report forms.

Main Outcomes and Measures  

    Neurological symptom prevalence and neurological examination scores were compared to those of control individuals. Tests for differences between survivors and control individuals were conducted using generalized linear mixed-effects models controlling for age and sex. Overdispersed Poisson models were used to test for computed neurological examination score differences. Neurological examination scores were developed for this study, representing the cumulative abnormalities on neurological examinations, denoted on standardized case report forms, with the general neurological examination score representing all examination abnormalities and the central nervous system score representing the central nervous system–specific abnormalities on examination.

Results  

    Analysis after serologic testing included 148 Ebola antibody-positive survivors (mean [SD] age, 34.8 [10.5] years; 74 [50%] female) and 81 antibody-negative contacts (mean [SD] age, 35.8 [12.6] years; 41 [51%] female). During acute infection, survivors reported headaches, altered mental status, and strokelike symptoms or meningoencephalitis (rarely). Survivors had significant neurological sequelae involving the entire neuraxis: cognitive dysfunction (83 [56.1%]), persistent headaches (98 [66.2%]), sleep abnormalities (40 [27.0%]), depression (73 [49.3%]), sexual dysfunction (48 [32.4%]), tremor (18 [20.3%]), fatigue (71 [51.1%]), cranial nerve abnormalities (60 [40.5%]), and sensory abnormalities (45 [30.4%]). Over 7 years’ follow-up, most survivors demonstrated improvement in neurological status. The final visit included 115 survivors (77.7%) and 61 close contacts (75.3%). Persistent symptoms at final evaluation in survivors compared to contacts were memory loss (66 [57.4%] vs 16 [26.2%], respectively; P < .001), irritability (42 [36.5%] vs 9 [14.8%], respectively; P = .006), and trouble concentrating (34 [29.6%] vs 6 [9.8%], respectively; P = .002).

Conclusions and Relevance  

    The findings indicate that Ebola virus infection is associated with neurological complications in survivors, with increased health care burden and socioeconomic consequences. These neurological issues generally improved with time, but some persisted long-term. Close neurological follow-up of EVD survivors may be warranted.

Source: 

Link: https://jamanetwork.com/journals/jamaneurology/fullarticle/2850237#251071811

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Evaluation of #antiviral #treatments for highly pathogenic avian #influenza virus #infections in #feline species

 

Abstract

In 2020, highly pathogenic avian influenza (HPAI) isolates from clade 2.3.4.4b emerged in Europe and spread globally, including in bovine hosts in the USA. Viruses from this clade cause minimal disease in dairy cattle, characterized by decreased milk production but low mortality rates. Infections have also occurred in feline hosts. In contrast to cows, infection of cats (and closely related species, including skunks and foxes) can result in severe neurological signs and mortality. Documented feline H5N1 infections from clade 2.3.4.4.b have a mortality rate of approximately 80% following rapid onset of clinical signs. No antiviral compounds have been tested in an experimental feline model; however, anecdotal clinical evidence suggests early treatment with oseltamivir may improve outcomes in felines with HPAI. Here, we show the in vitro efficacy of several influenza inhibitors in feline glial astrocyte (PG-4) and kidney (CRFK) cell culture models using the clade 2.3.4.4.b virus Tx2/24 (H5N1). The neuraminidase inhibitor oseltamivir carboxylate did not effectively inhibit viral replication in either cell line. The cap-dependent endonuclease inhibitor baloxavir exhibited the strongest inhibition of this virus, with EC50 values of 30 nM in PG-4 and 1 μM in CRFK cells. Amantadine and rimantadine, M2 ion channel inhibitors, were unable to completely inhibit viral replication in either cell line at any concentration utilized. The broad-spectrum nucleoside analog GS-441524 demonstrated little to no inhibition of viral replication in either cell line. Additionally, the mutagenic NHC analogs EIDD-1931 and EIDD-2801 successfully inhibited viral replication at the maximum tested concentration of 100 μM but exhibited significant cytotoxicity. Our findings suggest that baloxavir should be considered by veterinary clinicians as the first-line drug of choice when presented with felines or other species infected with HPAI.

Competing Interest Statement

The authors have declared no competing interest.

Funder Information Declared

Cornell Feline Health Center, Ithaca, US

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.06.09.730954v1

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#Antigenic mapping of #H2 #influenza viruses recognized by #ferret and #human sera and predicting antigenically significant sites

 

ABSTRACT

Influenza viruses cause hundreds of thousands of infections globally every year. In the past century, seasonal influenza viruses have included H1N1, H2N2, and H3N2 strains. H2N2 influenza viruses circulated in the human population between 1957 and 1968. Previously, our group demonstrated a lack of H2N2 influenza virus immunity in individuals born after 1968, as well as the effectiveness of hemagglutinin (HA)-based vaccines for multiple influenza virus subtypes. In this study, H2 antigenic maps and radial graphs were generated using previously published data from H2 HA vaccinations of ferrets and seasonal influenza vaccinations of humans. The antigenic maps revealed a stark difference in the clustering of HA antigens between ferrets and humans, and the radial graphs showed that specific antigen recognition varies greatly among different influenza preimmune ferrets. These maps also revealed the significant impact that different pre-existing immunities have on antigenic recognition and clustering of antigens after vaccine boost. From these data, we predicted two possible antigenically significant sites containing various mutations that have not been previously reported, and showed that one of these sites is relevant using mouse antisera.

Source: 

Link: https://journals.asm.org/doi/10.1128/msphere.00022-26

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Regional #Signals Preceding the 2026 #Bundibugyo Virus Disease #Outbreak

 

Highlights

    • Bundibugyo virus circulated undetected for months prior to outbreak declaration.

    • Four earlier regional hemorrhagic fever clusters flagged by open surveillance are unresolved.

    • These clusters warrant urgent reanalysis due to concern for regional spread.

Abstract

Background

The May 2026 Bundibugyo virus disease (BVD) outbreak in the Democratic Republic of the Congo was declared a Public Health Emergency of International Concern after substantial undetected community transmission. We describe regional surveillance signals detected by the Biothreats Emergence, Analysis, and Communications Network (BEACON), our open access event based surveillance program, in the weeks preceding outbreak declaration.

Methods

We reviewed BEACON reports of VHF-compatible illness clusters detected in the transboundary DRC-Uganda-Burundi-South Sudan region during March–April 2026, prior to the May 15 laboratory confirmation of BDBV.

Results

BEACON detected four temporally proximal VHF-compatible illness signals: (1) March 9, North Kivu Province—suspected Ebola case under investigation with unresolved laboratory results; (2) March 10, Kasaï Province—fatal hemorrhagic illness with secondary cases and negative Ebola PCR; (3) March 30, Burundi—35-case undiagnosed cluster near the DRC border with 5 deaths, negative testing for major filoviruses and >200 pathogens, pending metagenomic sequencing; (4) April 22, South Sudan—three suspected VHF cases with negative initial testing. All four signals shared a similar diagnostic phenotype: VHF-compatible presentation, mobilization of investigation teams, negative initial testing, and no publicly reported confirmed etiology. None were formally reported to have been resolved.

Conclusions

Our detection of four unresolved VHF signals preceding the confirmed BDBV outbreak highlights gaps in formal follow-up mechanisms for negative cases and fragmented regional diagnostic coordination. In light of confirmed BDBV circulation and Africa CDC's identification of 10 countries at high risk for spread, these preceding signals warrant urgent retrospective investigation and laboratory.

Source: 

Link: https://www.ijidonline.com/article/S1201-9712(26)00497-2/fulltext

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#UK Health Security Agency #update on the #hantavirus cruise ship #outbreak (June 10 '26): a probable case was retrospectively lab confirmed

 

Latest update

    UKHSA continues to work closely with partners in response to the hantavirus outbreak.

    UKHSA laboratories have confirmed a positive hantavirus test result for an individual in Tristan de Cunha, who was previously considered a probable case by WHO with exposure on MV Hondius. 

    This is not a new case.

    The samples were collected in May and the individual is now clinically well at home in Tristan de Cunha.

    All necessary public health actions have been carried out. 

    There is no change to the public health risk to the UK population from Hantavirus, which remains very low.

Source: 

Link: https://www.gov.uk/government/news/ukhsa-update-on-the-hantavirus-cruise-ship-outbreak

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#Estimation of the #Ebola #outbreak size in the #DRC

 

{Excerpt}

    The ongoing outbreak of Bundibugyo virus disease, a form of Ebola virus disease caused by the Bundibugyo virus, in the Democratic Republic of the Congo is evolving rapidly. As of May 27, 2026, 1031 suspected or confirmed cases of Bundibugyo virus disease had been reported from 14 health zones across three provinces (Ituri, Nord Kivu, and Sud Kivu) in the Democratic Republic of the Congo, including 240 suspected or confirmed deaths.1 Testing has rapidly expanded for routine and retrospective assessment of suspected cases (381 confirmed cases as of June 3, 2026). Deaths are harder to retrospectively assess, with investigations ongoing (64 confirmed deaths as of June 3, 2026). Suspected cases and deaths are no longer reported in recent situation reports.2 An additional 16 cases were confirmed in Uganda, as of June 4, 2026,3 with three of those among individuals travelling from Ituri, the Democratic Republic of the Congo.4,5 Together, these observations suggest that the epidemic has been larger than ascertained; however, the true magnitude remains uncertain. Estimating the outbreak size is important to assess the scale of this public health threat and appropriately calibrate surveillance and response efforts.

(...)

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(26)00299-9/fulltext?rss=yes

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Cryo-EM structures of #Měnglà virus GP reveal combined #Ebola- and #Marburg-like epitope masking strategies for #antibody evasion

 

Abstract

Ebola virus (EBOV) and Marburg virus (MARV) are highly lethal filoviruses that cause severe hemorrhagic fever in humans. A recently identified bat-borne filovirus, Měnglà virus (MLAV), uses the same NPC1 receptor as EBOV and MARV, raising concerns about its potential cross-species transmission. Here, we report cryo-EM structures of the MLAV surface glycoprotein (GP) in its unbound form and in complex with the MARV-neutralizing antibody MR191. MLAV GP exhibits distinctive structural features in the Wing and heptad repeat 1D (HR1D) regions, retains a visible Cap structure even after protease treatment, and contains a MARV GP-like α2 helix. MR191, a broadly neutralizing marburgvirus antibody that targets the conserved NPC1 receptor-binding pocket in MLAV GP, nonetheless exhibits impaired neutralizing activity, likely due to shielding by the MLAV Cap. In addition, the MLAV mucin-like domain, α2 helix, and HR1A region hinder binding by representative broadly neutralizing ebolavirus antibodies targeting the GP-waist, including 6D6, CA45, ADI-15878, and ADI-15946. Together, these results provide the first structural insights into MLAV GP and identify immune evasion driven by structural and sequence divergence as a major challenge for pan-filovirus antibody development.

Source: 

Link: https://www.pnas.org/doi/abs/10.1073/pnas.2529436123?af=R

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Rapid #Risk #Assessment: #Ebola #Bundibugyo virus disease, #DRC, #Uganda (#WHO, June 9 '26, summary)

 

Date and version of current assessment: 06 June 2026, v3  

Date(s) and version(s) of previous assessment(s): 15 May 2026, V1; 22 May 2026,V2 

Risk statement

    Following the publication of the second Rapid Risk Assessment (RRA) on 22 May 2026, the Bundibugyo virus disease (BVD) outbreak has continued to expand, particularly in the Democratic Republic of the Congo and, to a lesser extent, in Uganda. 

    During this period, a case was reported in a Congolese national who travelled from the Democratic Republic of the Congo, via Uganda, to the United Arab Emirates and then back to Uganda. 

    WHO is working with public health authorities in the United Arab Emirates and Uganda to gather additional information to assess the risk of exposure and facilitate contact tracing through the National International Health Regulations (IHR) Focal Point mechanism. 

    Following notification of the case, the United Arab Emirates authorities rapidly implemented risk assessment, contact tracing activities, follow-up of identified contacts, public health investigations, enhanced preparedness measures at points of entry, and coordination with relevant national and international partners. 

    Epidemiological investigations to date have not identified any secondary cases, local transmission, or evidence of onward spread in the country.   

    Additionally, as of 6 June, the outbreak in the Democratic Republic of the Congo has expanded considerably; the number of reported affected health zones has increased from 16 to 25, while the number of laboratory-confirmed cases increased from 63 to 515 and the number of confirmed deaths from four to 91 (CFR 17.7%). 

    The increase in the number of confirmed cases reflects both ongoing transmission and improvements in case detection through expanded testing and intensified contact tracing activities. 

    The number of reported suspected cases decreased from 661 to 117 following the testing of a backlog of samples and subsequent reclassification of suspected cases to either confirmed cases or noncases. 

    So far, at least 16 healthcare workers are among the confirmed cases. 

    Cases have been reported across all age groups, with most occurring among adults aged 20–49 years, and a slightly higher proportion among males. 

    To date, 12 patients have recovered. 

    The outbreak has also expanded geographically, with transmission reported in additional health zones in Ituri and North Kivu provinces. 

    The outbreak is now reported across 25 health zones in Ituri (17), North Kivu (seven), and South Kivu (one) provinces, with new affected areas identified in both Ituri and North Kivu.  

    In Uganda, as of 6 June, the number of reported confirmed cases increased from two to 19 (14 imported and five acquired in Uganda), including two deaths in imported cases. 

    All reported cases are from two districts (Kampala and Wakiso). 

    Five healthcare workers are among the confirmed cases, indicating transmission in healthcare settings. 

    To date, all cases in Uganda have been linked to importation from the Democratic Republic of the Congo or secondary cases linked to these; there has been no documented community transmission in Uganda.   

    In light of the continued evolution of the outbreak and newly available information, including the increase in the number of reported cases, geographic expansion, cross-border transmission to Uganda, and ongoing response activities, this RRA has been updated. 

    Based on these developments and the WHO Temporary Recommendations issued by the WHO Director-General following the declaration of a Public Health Event of International Concern (PHEIC) for the Ebola disease epidemic caused by Bundibugyo virus (BDBV) in the Democratic Republic of the Congo and Uganda, the risk for countries sharing land borders with countries with documented BDBV detection, currently the Democratic Republic of the Congo and Uganda, has been separated out from the risk for other countries in the African Region: the risk in countries sharing land borders remains high, while the risk for other countries in the African region is assessed as low. 

    Countries sharing land borders with the Democratic Republic of the Congo and/or Uganda have not reported confirmed cases to date. 

    Neighbouring countries have strengthened surveillance and point-of-entry (PoE) measures, although the extent of implementation may vary across countries.  

    The risk globally remains unchanged and is assessed as low.  

    The risk in the Democratic Republic of the Congo remains 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 key factors underpinning this assessment include:  

        • The outbreak has continued to expand rapidly since the previous assessment. Between 22 May and 6 June 2026, the number of confirmed cases increased more than eightfold from 63 to 515 cases, while the number of health zones with confirmed cases has increased by 56 % (from 16 to 25), indicating intensified transmission and geographic spread. 

        • The detection of cases in additional health zones in Ituri and North Kivu provinces and ongoing transmission among healthcare workers suggest that the outbreak continues to pose a very high risk of further spread within the Democratic Republic of the Congo. 

        • In Ituri province, 17 of the 36 health zones are now affected, with Aungba, Damas, Gety, Komanda, Lita, Mambasa and Mangala among the newly affected health zones. In North Kivu province, confirmed case detections in the Beni and Kyondo health zones have increased the number of affected health zones to seven out of 35. 

        • According to the most up-to-date sub-national risk stratification analysis, which will be used to further inform operational response priorities, there are a total of 159 health zones currently deemed affected or at risk; this classifies the level of community transmission and underscores the large geographic scale of response needed to control this outbreak.  

            o 25 health zones with confirmed cases, including 17 ‘hotspot’ health zones and eight  ‘active’ health zones{2} 

            o 19 high-risk health zones 

            o 115 at-risk health zones 

        • Epidemiological links and the full chain of transmission are not yet clearly established, and the source of the outbreak remains under investigation.  

        • Retrospective investigations identified suspected viral haemorrhagic fever cases occurring back in March 2026,  several weeks before outbreak confirmation, suggesting prolonged undetected transmission prior to May 2026 and the establishment of multiple disconnected transmission chains across affected communities and provinces. 

        • The affected area is characterized by intense population mobility linked to mining activities, trade, social ties and care seeking, with movement between rural and urban centres and across neighbouring provinces.  

        • Reports of patients avoiding or leaving treatment facilities, together with evidence of ongoing community mistrust of BVD prevention and response measures, raise concerns about reduced healthcare-seeking behaviour and under-detection of cases. As observed during previous Ebola disease outbreaks, community  fear and misinformation have hindered case detection, contact tracing, and isolation efforts, contributing to sustained transmission. Such challenges may facilitate ongoing spread within affected communities and complicate outbreak control measures. 

        • Reports of numerous community deaths and challenges in the implementation and community acceptance of safe and dignified burial (SDB) practices are of concern. Traditional burial practices often involve direct contact with the deceased, which may facilitate transmission and contribute to the persistence of community-based transmission chains. 

        • Ongoing conflict in Ituri and North Kivu provinces restricts the movement of surveillance teams, limits the deployment of Rapid Response Teams, and hinders the secure transport of laboratory samples, as well as posing challenges to contact tracing, safe and dignified burials and control of movement of high-risk contacts in those conflict zones. 

        • Limited healthcare infrastructure, combined with inadequate and insufficient Ebola Treatment Centre (ETC) and isolation capacity, may hinder effective case management and infection prevention and control measures. The mixing of suspected and confirmed cases in healthcare facilities increases the risk of nosocomial transmission and may further amplify the outbreak. 

        • Delays in laboratory confirmation resulting from stockouts of testing supplies and limited diagnostic capacity have hindered the timely detection, isolation, and management of cases. 

        • Infection among at least 16 healthcare workers, including a laboratory technician, together with low infection prevention and control (IPC) scorecard performance in affected areas, indicate a high risk of exposure in healthcare settings and significant gaps in IPC. 

        • Early and intensive  supportive care remains the only treatment option for BVD, for which no licensed vaccine or specific therapeutics are currently available for prevention and treatment.  

        • Community protection capacities remain insufficient in several affected areas, including limited social listening, community feedback mechanisms, rumour management, engagement of trusted local leaders and Community Health Workers (CHWs), and systematic use of community insights to inform operational decision-making. These gaps may contribute to delayed care-seeking, underreporting, reduced acceptance of response measures and continued transmission. 

    The level of risk for Uganda is still assessed as High due to: 

        • Confirmed cross-border spread through imported cases to Uganda. 

        • As of 6 June 2026, Uganda had reported 19 cases linked to the outbreak in the Democratic Republic of the Congo, following the importation of two cases who travelled to Uganda to seek medical care. Among the reported cases, five are healthcare workers, indicating transmission in healthcare settings. 

        • Despite the suspension of passenger transport services between Uganda and the Democratic Republic of the Congo, including flights, buses, and ferries, cross-border population movement is likely to continue through informal and uncontrolled crossing points. The porous border, together with intense cross-border mobility associated with mining, trade, family visits, healthcare-seeking, displacement or population movements linked to insecurity, increases the likelihood of continued cross-border transmission. 

        • Potential for undetected chains of transmission in border communities. 

        • Preliminary analyses of population movement and cross-border mobility patterns have identified Kisoro, Kabale, Kanungu, Rukungiri, Kasese, Kikuube, Hoima, Pakwach, Nebbi, Arua, Zombo, Koboko, and Yumbe as the districts at increased risk of importation and subsequent transmission of BVD from the Democratic Republic of Congo. 

        • Ongoing epidemiological links along the eastern Democratic Republic of the Congo–western Uganda corridor, historically affected by Ebola outbreaks, including Bundibugyo and Sudan virus disease outbreaks. 

    The risk for countries with land borders adjoining countries with documented BDBV detection, is assessed as high  based on the following factors: 

        • Sustained population mobility across porous borders linked to cross-border trade and mining activities, combined with operational constraints resulting from insecurity, displacement, and limited healthcare access, increase the risk of continued transmission and hinder outbreak control measures. 

        • Insufficient laboratory capacity, coupled with limited experience in BVD surveillance, case management, infection prevention and control, contact tracing, and outbreak response, may reduce the ability of some neighbouring countries to rapidly detect and contain imported cases. 

        • Variable levels of readiness for community engagement, community-based surveillance, social listening, rumor management and community feedback systems may limit the ability of some neighbouring countries to rapidly identify, understand and respond to community concerns following an imported case. 

        • There are variations in capacities and experiences across these countries.  

    The level of risk for the rest of the Africa region and at the global level is assessed as low due to: 

        • At present the outbreak remains geographically limited to the Democratic Republic of the Congo, with exportation of cases only to Uganda. 

        • No evidence suggests sustained international transmission of BVD beyond the Democratic Republic of the Congo and Uganda border areas currently. 

        • The exportation of cases through international travel, particularly during the asymptomatic incubation period, is possible and may be anticipated; however, this does not change the overall risk assessment, and the risk of global spread remains low. 

(...)

1 Confidence refers to the level of confidence in the data/information or the quality of the evidence available at the time the RRA is conducted. Poor quality information may increase the overall perceived risk due to the incertitude in the assessment. 

2 ‘Hotspot’ health zones refer to those with the highest burden of active transmission among those with confirmed cases reported; ‘active’ refers to all other health zones with confirmed cases reported 

(...)

Source: 

Link: https://www.who.int/publications/m/item/who-rapid-risk-assessment-ebola-disease-caused-by-bundibugyo-virus--democratic-republic-of-the-congo--uganda-and-countries-with-land-borders-adjoining-countries-with-documented-bdbv-detection-v3

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