Cardiopulmonary Failure in #Hantavirus Disease: Mechanisms, Recognition, and #ECMO-Based Management

 

Abstract

Background: 

Hantavirus pulmonary syndrome (HPS), also designated hantavirus cardiopulmonary syndrome, is caused by New World hantaviruses, principally Sin Nombre virus in North America and Andes virus in South America. The syndrome is characterized by rapidly progressive noncardiogenic pulmonary edema and myocardial depression, with case fatality rates of 25% to 40%. A 2026 outbreak aboard an expedition cruise ship in the South Atlantic, comprising 13 cases and three deaths, confirmed that Andes virus can be transmitted between humans in a confined setting remote from the rodent reservoir. 

Methods: 

Virological, pathophysiological, clinical, and therapeutic aspects of HPS were reviewed, with particular emphasis on cardiopulmonary mechanisms. Sources were identified through PubMed, Scopus, and Google Scholar, with priority given to original research articles, clinical series, and controlled trials published through 2025. Literature published in English and Spanish was included. 

Results: 

Pathogenic hantaviruses enter endothelial cells and platelets via αvβ3 integrins, disrupting the VEGF-VEGFR2 signaling axis and rendering endothelial cells hypersensitive to physiological VEGF concentrations. Expansion of CD8+ T cells and activated macrophages releases TNF-alpha, IFN-gamma, and nitric oxide, amplifying microvascular permeability and contributing to myocardial depression. Autopsy studies demonstrate direct hantaviral myocarditis with viral antigen in cardiac endothelium and interstitial macrophages. Transpulmonary thermodilution confirms simultaneous hypovolemia, reduced global ejection fraction, and elevated extravascular lung water. Because the incubation period is long and the cardiopulmonary phase is substantially immune-mediated, seroconversion precedes rather than follows clinical deterioration, which preserves the diagnostic utility of IgM serology in a disease that can kill within 48 h. VA-ECMO initiated at the first signs of cardiopulmonary decompensation has reported survival rates approaching 80% in selected experienced centers. No antiviral has demonstrated efficacy in controlled trials during the cardiopulmonary phase, and no licensed vaccine exists. 

Conclusions: 

HPS produces a mixed shock state through increased microvascular permeability, T cell-mediated immunopathology, and direct myocarditis. Management follows a stepwise algorithm: suspected HPS triggers immediate complete blood count with peripheral blood smear and concurrent hantavirus IgM serology and RT-PCR, followed by ICU admission, conservative fluid resuscitation guided by transpulmonary thermodilution, and early contact with an ECMO-capable center at the first sign of rising lactate, falling cardiac index, refractory shock, arrhythmia, or rapid oxygenation failure.

Source: 

Link: https://www.mdpi.com/1999-4915/18/8/915

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#Treatment of #CCHF with supportive care, #favipiravir, and avatrombopag

 

Abstract

We report a severe Crimean-Congo Hemorrhagic Fever case treated with favipiravir and avatrombopag in a high-level isolation unit. This multimodal approach was associated with rapid platelet recovery, reduced transfusion requirements, and viral clearance. Combining targeted antivirals with thrombopoietin receptor agonists represents a promising strategy for managing severe CCHF coagulopathy.

Source: 

Link: https://academic.oup.com/cid/advance-article-abstract/doi/10.1093/cid/ciag415/8765585?redirectedFrom=fulltext

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Conserved #influenza A #epitope candidate regions and a benchmark of ESM-2 #sequence features

 

Abstract

Influenza A virus antigenic drift forces annual vaccine reformulation, motivating the search for conserved epitope candidates that could support broadly protective vaccines. We systematically screened influenza A virus sequences (H1N1, H3N2, H5N1; nine viral proteins) to define 98 conserved candidate regions, 38 of which were identical across the H1N1, H3N2, and H5N1 consensus sequences, all in the polymerase complex and nucleoprotein (PB2, PB1, PA, NP), whereas the ten surface-glycoprotein (HA/NA) candidates were subtype-specific. We then benchmarked two protein-language-model (ESM-2) features against alignment conservation. Group-masked log-probability correlated moderately with MSA conservation (Spearman rho = 0.25 to 0.39 for HA) but provided no incremental value for T-cell epitope discrimination (change in AUROC +0.004, p = 0.46); attention-derived contact-density was not a valid solvent-accessibility proxy. A curated antibody-epitope benchmark (22 clusters, 5 neutralization-supported) was underpowered for a high-confidence B-cell test. We document data-quality and reproducibility pitfalls (length heterogeneity, coordinate mapping, and pseudoreplication) and release the auditable benchmark. These results provide an auditable candidate resource and show that, in the evaluated benchmarks, ESM-2 sequence scores did not improve epitope prioritization beyond alignment-derived conservation.

Competing Interest Statement

The authors have declared no competing interest.

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.08.16.745106v1

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#USA, #Michigan DHHS confirms #human eastern equine #encephalitis case (August 19 '26)

 

Residents urged to take precautions against mosquito bites

LANSING, Mich. - The Michigan Department of Health and Human Services (MDHHS) has confirmed a locally acquired case of eastern equine encephalitis (EEE) in a Roscommon County resident and reminds Michiganders to take steps to protect themselves against mosquito-borne diseases.

    This is the first EEE human case reported in Michigan since 2021. 

    No additional information will be provided about this individual.

    State and local health departments, along with the Michigan Department of Agriculture and Rural Development and Michigan Department of Natural Resources, have been monitoring and will continue to monitor for signs of EEE in humans, mosquitos, domestic animals and wildlife. 

    Prior to this case, no animal EEE activity has been detected in Michigan this year. 

    Additional mosquito trapping and testing is underway in Roscommon County to assess the level of risk in the area. Information about human, animal and mosquito pool testing is available in a weekly arboviral report.

    “It is vital that Michigan residents take precautions against mosquito bites as mosquitoes can carry diseases that can have devastating health effects,” said Dr. Natasha Bagdasarian, chief medical executive. 

    “EEE is one of the most dangerous mosquito-borne diseases in the U.S., with a 30% fatality rate among people who become ill.”

    EEE virus is spread to people by the bite of an infected mosquito. EEE is a rare but serious disease. Only a few human cases are reported each year in the United States.  

    People who become ill with EEE may experience fever, headache, chills and nausea. In some cases, symptoms may progress to inflammation of the brain, signaled by disorientation, seizures and coma. 

    Physicians treating patients with these symptoms should consider testing for EEE and other mosquito-borne viruses and report suspect cases to their local health department. The MDHHS Bureau of Laboratories offers comprehensive testing for the arboviruses of concern in Michigan.

    The best way to prevent EEE, or any other mosquito-borne illness, is to reduce the number of mosquitoes around your home and to take steps to avoid mosquito bites, including:

        ° Use U.S Environmental Protection Agency-registered insect repellents with one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus or para-menthane-diol and 2-undecanone. Follow the product label instructions and reapply as directed.

        ° Do not use insect repellent on children under 2 months old. Instead, dress your child in clothing that covers arms and legs and cover crib, stroller and baby carrier with mosquito netting.

        ° Wear shoes and socks, light-colored long pants and long-sleeved shirts when outdoors.

        ° Make sure doors and windows have tight-fitting screens. Repair or replace screens that have tears or other openings.

        ° Use bed nets when sleeping outdoors or in conditions with no window screens.

        ° Once a week eliminate all sources of standing water that can support mosquito breeding around your home, including water in bird baths, abandoned swimming pools, wading pools, old tires and any other object holding water.

    For more information on the human health impact of EEE, visit CDC.gov/EEE. For updates on EEE activity in Michigan, visit Michigan.gov/EEE.

Source: 

Link: https://www.michigan.gov/mdhhs/inside-mdhhs/newsroom/2026/08/19/eee

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Of Mice and Men: #Updates on #Hantavirus Disease and #Diagnostics

 

Abstract

Hantaviruses are a diverse and widespread group of zoonotic viruses under the Orthohantavirus genus that can cause severe acute cardiopulmonary or renal disease. Hantavirus species are grouped generally as either New World or Old World based on geographic distribution, which is influenced by their respective host reservoir including rodents. Although there is no specific treatment for hantaviruses, recognizing clinical presentation and interpreting laboratory results for case identification can improve patient management. Here we review the epidemiology, clinical manifestations, and diagnostic testing options for hantavirus infection.

Source: 

Link: https://www.sciencedirect.com/science/article/abs/pii/S1386653226000843?dgcid=rss_sd_all

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#Maraviroc Inhibits #SARS-CoV-2 Through Variant-Dependent Effects on Viral Entry and #Mpro Activity Using Single-Round Infectious Particle and Virus-like Particle Models

 

Abstract

Maraviroc (MVC), a CCR5 antagonist, has been proposed as a potential antiviral agent against SARS-CoV-2; however, its mechanism of action across viral variants remains unclear. Here, we evaluated the antiviral activity of MVC against SARS-CoV-2 wild-type (WT) and Omicron BA.1 variants using single-round infectious particles (SRIPs), virus-like particles (VLPs), and cell-based assays, with a focus on its impact on viral entry and Mpro function. MVC potently inhibited infection of both WT and BA.1 SRIPs in Vero E6 cells, exhibiting EC50 values of 0.0065 μM and 0.016 μM, respectively. Time-of-addition assays revealed that MVC primarily targets the early phase of infection, with the strongest inhibition observed at the viral entry stage, while moderate effects were detected during attachment and post-entry stages. Fluorescence-labeled VLP imaging demonstrated distinct entry pathways, with WT predominantly entering via plasma membrane fusion and BA.1 via endocytosis, independent of cell type. MVC altered WT-VLP trafficking by promoting internalization and lysosomal localization, whereas it had minimal impact on BA.1 internalization. In spike-mediated cell–cell fusion assays, MVC preferentially inhibited WT spike-driven syncytium formation but showed limited effects on BA.1 or BA.4 fusion, while more effectively reducing Omicron spike-mediated binding. At the post-entry stage, MVC inhibited SARS-CoV-2 main protease (Mpro) activity, with BA.1 Mpro (P132H) exhibiting greater sensitivity (IC50 = 0.496 µM) than WT (1.869 µM). Collectively, these findings demonstrate that MVC exerts variant-dependent antiviral effects by targeting viral entry, modulating trafficking pathways, and inhibiting Mpro activity. This study highlights MVC as a multi-stage inhibitor with differential efficacy against SARS-CoV-2 variants, providing insights into its potential therapeutic application.

Source: 

Link: https://www.mdpi.com/1999-4915/18/8/911

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#Influenza at #human - #animal #interface - Summary & #risk #assessment, from 8 July to 7 August '26 (WHO, edited): 2 new #H5N1 cases in #Bangladesh & #Cambodia, 8 new #H9N2 cases in #China

Influenza at the human - animal #interface - Summary and risk assessment, from 8 July to 7 August 2026 {1}

    • New human cases {2}: 

        * From 8 July to 7 August 2026, based on reporting date, detections of influenza A(H5N1) in one human and influenza A(H9N2) in eight humans  were officially reported. 

    • Circulation of influenza viruses with zoonotic potential in animals: 

        ° High pathogenicity avian influenza (HPAI) events in poultry and non-poultry animal species continue to be reported to the World Organisation for  Animal Health (WOAH).{3} The Food and Agriculture Organization of the United Nations (FAO) also provides a global update on avian influenza viruses with  pandemic potential.{4} Additionally, low pathogenicity avian influenza viruses as  well as swine influenza viruses continue to circulate in animal populations.

    • Risk assessment {5}: 

        * There have been no reports of sustained human-to-human transmission associated with the above-mentioned human infection events.  Based on information available at the time of this risk assessment update, the  overall public health risk from currently known influenza A viruses detected at the human-animal interface has not changed and, at present, these  viruses are not thought to be capable of sustained human-to-human transmission, although this could change as they evolve. Although human  infections with viruses of animal origin are infrequent, they are not unexpected at  the human-animal interface.

    • IHR compliance {6}: 

        * This includes any influenza A virus that has demonstrated the capacity  to infect a human and its haemagglutinin (HA) gene (or protein) is not a  mutated form of those, i.e. A(H1) or A(H3), circulating widely in the human  population. Information from these notifications is critical to inform risk  assessments for influenza at the human-animal interface.

Avian influenza viruses in humans

    ° A(H5N1), Bangladesh

        § The case included in the risk assessment of 7 July 2026 in a child from Sylhet Division was confirmed as an A(H5N1) virus infection.

    ° A(H5N1), Cambodia

        § On 10 July 2026, Cambodia notified WHO of one laboratory-confirmed human case of avian influenza A(H5N1) infection detected in a child in Phnom Penh who developed a fever on 30 June 2026. After several days of  treatment at a private clinic without improvement, she was admitted to hospital  on 7 July with bronchopneumonia. Oropharyngeal and nasopharyngeal swabs  collected on 8 July were tested at the Institut Pasteur du Cambodge and reverse  transcription polymerase chain reaction (RT-PCR) testing confirmed influenza  A(H5N1) on 10 July, with positive results confirmed through repeat testing. The  specimen was subsequently tested at the National Institute of Public Health, which  also confirmed influenza A(H5N1). The patient was in stable clinical condition, treated with oseltamivir and subsequently recovered.

        § Sequence analysis identified the virus as a clade 2.3.2.1e virus,  closely related to viruses that have been circulating in poultry and causing  sporadic human infections in Cambodia since 2023.

        § Following laboratory confirmation, the national and Phnom Penh  Municipal Rapid Response Teams, in collaboration with the Ministry of Agriculture,  Forestry and Fisheries and local authorities, initiated epidemiological,  environmental and animal health investigations, including active case finding and assessments of potential poultry and environmental exposures. 

        § Neighbouring households kept fighting cocks and free-range chickens  and the patient visited one of these households prior to symptom onset.  The child also had exposure to areas where chicken droppings were found. 

        § At the time of reporting, three animal samples collected from poultry  in neighbouring households for laboratory testing tested negative for influenza  A(H5N1). 

        § Contacts of the case tested negative for influenza A(H5N1) and two  tested positive for SARS-CoV-2.

        § Since 2023, Cambodia has reported 39 laboratory-confirmed human cases, including 16 deaths.

Risk assessment for avian influenza A(H5N1) viruses:

    1. What is the current global public health risk of additional human cases of  infection with avian influenza A(H5N1) viruses?

        ° Most human infections so far have been reported in people exposed to  A(H5N1) viruses, for example, through contact with infected poultry or contaminated environments, including live poultry markets, and occasionally  infected mammals and contaminated environments. As long as the viruses  continue to be detected in animals and related environments humans are exposed  to, further human cases associated with such exposures are expected  but remain unusual. The impact for public health if additional sporadic cases are detected is minimal. 

        ° The current overall global public health risk is low.

    2. What is the likelihood of sustained human-to-human transmission of avian  influenza A(H5N1) viruses related to the events above?

        ° No sustained human-to-human transmission has been identified  associated with the recent reported human infections with avian  influenza A(H5N1) viruses. There has been no reported human-to-human  transmission of A(H5N1) viruses since 2007, although there may be gaps in  investigations. 

        ° In 2007 and the years prior, small clusters of A(H5) virus infections in  humans were reported, including some involving health care workers, where  limited human-to-human transmission could not be excluded; however, sustained human-to-human transmission was not reported. 

        ° Current evidence suggests that influenza A(H5N1) viruses related to  these events did not acquire the ability to efficiently transmit between people.

    3. What is the likelihood of international spread of avian influenza A(H5N1) viruses  by travellers?

        ° Should infected individuals from affected areas travel internationally,  their infection may be detected in another country during travel or after arrival. If  this were to occur, further communitylevel spread is considered unlikely as current evidence suggests these viruses have not acquired the ability to transmit easily among humans.  

    ° A(H9N2), China

        § Between 7 July and 5 August 2026, China notified WHO of eight laboratory-confirmed human cases of A(H9N2) virus infection. 

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        § All cases had direct or indirect exposure to poultry and/or local live  bird markets. Samples from environments associated with the likely area of  exposure of the cases tested positive for A(H9) viruses. 

        

        § No further cases were detected among contacts of these cases.

Risk assessment for avian influenza A(H9N2):

    1. What is the global public health risk of additional human cases of infection with  avian influenza A(H9N2) viruses?

        ° Most human cases follow exposure to the A(H9N2) virus through  contact with infected poultry or contaminated environments. Most human  infections of A(H9N2) to date have resulted in mild clinical illness. Since the  virus is endemic in poultry in multiple countries in Africa and Asia, additional human cases associated with exposure to infected poultry or  contaminated environments are expected but remain unusual. 

        

        ° The impact to public health if additional sporadic cases are detected is 

minimal. 

        ° The overall global public health risk is low.

    2. What is the likelihood of sustained human-to-human transmission of avian  influenza A(H9N2) viruses related to these events?

        ° At the present time, no sustained human-to-human transmission has been identified associated with the recently reported human infections with  A(H9N2) viruses. Current evidence suggests that A(H9N2) viruses from these  cases did not acquire the ability of sustained transmission among humans.

    3. What is the likelihood of international spread of avian influenza A(H9N2)  virus by travellers?

        ° Should infected individuals from affected areas travel internationally,  their infection may be detected in another country during travel or after arrival. If  this were to occur, further community level spread is considered unlikely as  current evidence suggests the A(H9N2) virus subtype has not acquired the ability  to transmit easily among humans.

Overall risk management recommendations:

Surveillance and investigations

    • Due to the constantly evolving nature of influenza viruses, WHO  continues to stress the importance of global strategic surveillance in animals and  humans to detect virologic, epidemiologic and clinical changes associated with  circulating influenza viruses that may affect human (or animal) health. Continued  vigilance is needed within affected and neighbouring areas to detect infections in  animals and humans. Close collaboration with the animal health and environment  sectors is essential to understand the extent of the risk of human exposure and to prevent and control the spread of animal influenza. WHO has published  guidance on surveillance for human infections with avian influenza A(H5) viruses.

    • As the extent of influenza virus circulation in animals is not clear,  epidemiologic and virologic surveillance and the follow-up of suspected human  cases should continue systematically. Guidance on investigation of non-seasonal  influenza and other emerging acute respiratory diseases has been published on the WHO website.

    • Countries should increase avian influenza surveillance in domestic and wild birds, enhance surveillance for early detection in cattle populations in  countries where HPAI is known to be circulating, include HPAI as a differential  diagnosis in non-avian species, including cattle and other livestock populations,  with high risk of exposure to HPAI viruses; monitor and investigate cases in non- avian species, including livestock, report cases of HPAI in all animal species, including unusual hosts, to WOAH and other international organizations,  share genetic sequences of avian influenza viruses in publicly available databases,  implement preventive and early response measures to break the HPAI  transmission cycle among animals through movement restrictions of  infected livestock holdings and strict biosecurity measures in all holdings, employ  good production and hygiene practices when handing animal products, and protect persons in contact with suspected/infected animals.{7} More guidance can be  found from WOAH and FAO.

    • When there has been human exposure to a known outbreak of an  influenza A virus in domestic poultry, wild birds or other animals – or when there  has been an identified human case of infection with such a virus – enhanced  surveillance in potentially exposed human populations becomes necessary.  Enhanced surveillance should consider the health care seeking behaviour of the  population, and could include a range of active and passive health care and/or  communitybased approaches, including: enhanced surveillance in local influenza- like illness (ILI)/SARI systems, active screening in hospitals and of groups that  may be at higher occupational risk of exposure, and inclusion of other sources  such as traditional healers, private practitioners and private diagnostic  laboratories.

    • Vigilance for the emergence of novel influenza viruses with pandemic  potential should be maintained at all times including during a non-influenza  emergency. In the context of the cocirculation of SARS-CoV-2 and influenza viruses, WHO has updated and published practical guidance for integrated surveillance.

Notifying WHO

    • All human infections caused by a new subtype of influenza virus are  notifiable under the International Health Regulations (IHR, 2005).{8,9} State  Parties to the IHR (2005) are required to immediately notify WHO of any laboratory-confirmed {10} case of a recent human infection caused by an influenza A virus with the potential to cause a pandemic {11}. Evidence of illness  is not required for this report. Evidence of illness is not required for this report.

    • WHO published the case definition for human infections with avian  influenza A(H5) virus requiring notification under IHR (2005):  https://www.who.int/teams/global-influenzaprogramme/avian-influenza/case-definitions.

Virus sharing and risk assessment

    • It is critical that these influenza viruses from animals or from humans  are fully characterized in appropriate animal or human health influenza reference  laboratories. Under WHO’s Pandemic Influenza Preparedness (PIP) Framework,  Member States are expected to share influenza viruses with pandemic potential on  a timely basis {12} with a WHO Collaborating Centre for influenza of GISRS. The viruses are used by the public health laboratories to assess the risk of  pandemic influenza and to develop candidate vaccine viruses.

    • The Tool for Influenza Pandemic Risk Assessment (TIPRA) provides an in-depth assessment of risk associated with some zoonotic influenza viruses –  notably the likelihood of the virus gaining human-to-human transmissibility, and  the impact should the virus gain such transmissibility. TIPRA maps relative risk  amongst viruses assessed using multiple risk elements. The results of TIPRA  complement those of the risk assessment provided here, and those of prior TIPRA  risk assessments are published at http://www.who.int/teams/global-influenza-programme/avianinfluenza/tool-for-influenza-pandemic-risk-assessment-(tipra).

Risk reduction

    • Given the observed extent and frequency of avian influenza in poultry, wild birds and some wild and domestic mammals, the public should  avoid contact with animals that are sick or dead from unknown causes, including  wild animals, and should report dead birds and mammals or request their removal  by contacting local wildlife or veterinary authorities.

    • Eggs, poultry meat and other poultry food products should be properly  cooked and properly handled during food preparation. Due to the potential health  risks to consumers, raw milk should be avoided. WHO advises consuming  pasteurized milk. If pasteurized milk isn’t available, heating raw milk until it boils makes it safer for consumption.

    • WHO has published practical interim guidance to reduce the risk of  infection in people exposed to avian influenza viruses.

Trade and travellers

    • WHO advises that travellers to countries with known outbreaks of animal influenza should avoid farms, contact with animals in live animal markets,  entering areas where animals may be slaughtered, or contact with any surfaces  that appear to be contaminated with animal excreta. Travelers should also wash  their hands often with soap and water. All individuals should follow good food safety and hygiene practices.

    • WHO does not advise special traveller screening at points of entry or  restrictions with regards to the current situation of influenza viruses at the  human-animal interface. For recommendations on safe trade in animals and  related products from countries affected by these influenza viruses, refer to WOAH guidance.

Links:

    ° WHO Human-Animal Interface web page

https://www.who.int/teams/global-influenza-programme/avian-influenza

    ° WHO Influenza (Avian and other zoonotic) fact sheet

https://www.who.int/news-room/fact-sheets/detail/influenza-(avian-and-other-zoonotic)

    ° WHO Protocol to investigate non-seasonal influenza and other emerging acute respiratory diseases

https://www.who.int/publications/i/item/WHO-WHE-IHM-GIP-2018.2

    ° WHO Public health resource pack for countries experiencing outbreaks of influenza in animals:

https://www.who.int/publications/i/item/9789240076884

    ° Cumulative Number of Confirmed Human Cases of Avian Influenza A(H5N1) Reported to WHO

https://www.who.int/teams/global-influenza-programme/avian-influenza/avian-a-h5n1-virus

    ° Avian Influenza A(H7N9) Information

https://www.who.int/teams/global-influenza-programme/avian-influenza/avian-influenza-a-(h7n9)-virus

    ° World Organisation of Animal Health (WOAH) web page: Avian Influenza

https://www.woah.org/en/home/

    ° Food and Agriculture Organization of the United Nations (FAO) webpage: Avian Influenza

https://www.fao.org/animal-health/avian-flu-qa/en/

    ° WOAH/FAO Network of Expertise on Animal Influenza (OFFLU)

http://www.offlu.org/

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{1} This summary and assessment covers information confirmed during this  period and may include information received outside of this period.

{2} For epidemiological and virological features of human infections with animal  influenza viruses not reported in this assessment, see the reports on human cases  of influenza at the human-animal interface published in the Weekly Epidemiological Record here.

{3} World Organisation for Animal Health (WOAH). Avian influenza. Global  situation. Available at: https://www.woah.org/en/disease/avian-influenza/#ui-id-2.

{4} Food and Agriculture Organization of the United Nations (FAO). Global Avian  Influenza Viruses with Zoonotic Potential situation update. Available at:  https://www.fao.org/animal-health/situation-updates/global-aiv-withzoonotic-potential.

{5} World Health Organization (2012). Rapid risk assessment of acute public  health events. World Health Organization. Available at:  https://iris.who.int/handle/10665/70810.

{6} World Health Organization. Case definitions for the four diseases requiring  notification in all circumstances under the International Health Regulations  (2005). Available at: https://www.who.int/publications/m/item/case-definitions-for-the-four-diseases-requiring-notification-towho-in-all-circumstances-under-the-ihr-(2005).

{7} World Organisation for Animal Health. Statement on High Pathogenicity Avian  Influenza in Cattle, 6 December 2024 (https://www.woah.org/en/high-pathogenicity-avian-influenza-hpai-in-cattle/).

{8} World Health Organization. International Health Regulations (2005), as  amended through resolutions WHA67.13 (2014), WHA75.12 (2022), and  WHA77.17 (2024) (https://apps.who.int/gb/bd/pdf_files/IHR_2014-2022-2024-en.pdf).

{9} World Health Organization. Case definitions for the four diseases requiring  notification in all circumstances under the International Health Regulations (2005)  (https://www.who.int/publications/m/item/casedefinitions-for-the-four-diseases-requiring-notification-to-who-in-all-circumstances-under-the-ihr-(2005)).

{10} World Health Organization. Manual for the laboratory diagnosis and  virological surveillance of influenza (2011)  (https://apps.who.int/iris/handle/10665/44518).

{11} World Health Organization. Pandemic influenza preparedness framework for  the sharing of influenza viruses and access to vaccines and other benefits, 2nd  edition (https://iris.who.int/handle/10665/341850).

{12} World Health Organization. Operational guidance on sharing influenza  viruses with human pandemic potential (IVPP) under the Pandemic Influenza  Preparedness (PIP) Framework (2017) (https://apps.who.int/iris/handle/10665/259402).

Source: 

Link: https://www.who.int/publications/m/item/influenza-at-the-human-animal-interface-summary-and-assessment--7-august-2026

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The return of #H1N1: Reemergence of the #influenza virus A subtype H1N1 in 1977

 

Abstract

Four major influenza pandemics and two notable outbreaks have been recorded since 1900. This paper discusses the history of the 1977 influenza virus A H1N1 outbreak and re-emergence, often referred to as the “Russian flu” or the “red flu". We describe the likely events leading to the outbreak, including a brief history of the 1976 H1N1 outbreak in a military base in the United States. We reconstruct the spread of the H1N1 virus across the globe in 1977–1978 and discuss the epidemiology of the outbreak. We describe the likely origins of this unusual outbreak mainly affecting young people, including opinions and evidence pointing towards an unnatural origin. Finally, we outline the vaccines developed and vaccination campaigns that were carried out to combat the outbreak.

Source: 

Link: https://www.sciencedirect.com/science/article/pii/S0264410X26007723?via%3Dihub

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#Ebola #Bundibugyo Virus Disease #Outbreak, #DRC, #Uganda - Situation #Report No. 14, Data as of 16 August '26 (WHO, edited): 5,021 cases & 2,378 deaths in DRC

 

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Event description

Democratic Republic of the Congo

    The Bundibugyo virus disease (BVD) outbreak in the Democratic Republic of the Congo has expanded to a sixth province, with the detection of a confirmed  case in Bas-Uélé province in the north-east, indicating further geographic  spread beyond the main transmission areas in the eastern part of the country. 

    Since External Situation Report #13, an additional 640 confirmed cases and 367 confirmed deaths have been reported, reflecting continued sustained  transmission and high mortality. 

    The crude case fatality ratio (CFR) has increased from 45.9% to 47.4%,  continuing the upward trend observed over several weeks.

    As of 16 August 2026, a total of 5 021 confirmed cases, including 2 378 confirmed deaths have been reported across 55 health zones in six provinces. 

    Buta health zone in Bas-Uélé province and Tshopo health zone in Tshopo  province are the latest affected health zones. 

    Ituri remains the epicentre, accounting for 84.8% of cumulative confirmed  cases and 79.0% of cumulative confirmed deaths.

Figure 1. Daily growth trend in confirmed Bundibugyo virus disease cases in the Democratic Republic of the Congo, by date of report, as of 16 August 2026

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    During the most recent 21 days (27 July – 16 August 2026), a total of 1 759 confirmed cases and 941 confirmed deaths were reported nationally. 

    Transmission remained concentrated in Ituri, which accounted for 1 356  cases (77.1%) and 671 deaths (71.3%), followed by Nord-Kivu with 293 cases  (16.7%) and 224 deaths (23.8%), and Haut-Uélé with 101 cases (5.7%) and 42  deaths (4.5%). 

    Compared with the preceding 21-day period (6 – 26 July 2026), the  number of newly reported cases increased by 121 (+7.4%), and deaths by 25  (+2.7%). However, trends varied substantially between provinces. In Ituri, newly  reported cases and deaths declined by 68 (−4.8%) and 97 (−12.6%)  respectively. 

    In contrast Nord-Kivu reported an increase of 123 newly reported cases  (+72.4%) and 101 deaths (+82.1%). Haut-Uélé recorded the largest relative  increase, with 61 additional newly reported cases (+156.4%) and 21 additional  newly reported deaths (+100.0%). Tshopo remained a smaller transmission focus,  while the detection of a case and death in Bas-Uélé indicates further  geographic expansion.

    At the health-zone level, transmission remained geographically widespread. Of the 55 health zones affected since the start of the outbreak, 47  (85.5%) reported at least one confirmed case during the most recent 21 days.  

    Eight health zones reported no new confirmed cases during this period: Adja, Ariwara, Boga and Kambala in Ituri; Goma in NordKivu; Rungu in Haut-Uélé; Lubunga in Tshopo; and Miti-Murhesa in Sud-Kivu. 

    Seven health zones reported confirmed cases for the first time since the  beginning of the outbreak: Gombari in Haut-Uélé, Lubero in Nord-Kivu, Bafwasende, Kabondo, Tshopo and Wanie-Rukula in Tshopo, and Buta in Bas-Uélé.  This indicates continued geographic expansion, including into previously  unaffected health zones.

    Despite this expansion, transmission remains highly concentrated in a limited number of health zones. Bunia, Rwampara, Nizi, Katwa, Mongbwalu and  Nia-Nia together reported 1 186 cases during the most recent 21 days, accounting  for 67.4% of all cases reported nationally during this period. 

    The distribution of transmission is also changing. Cases increased  substantially in Bunia (+80; +24.9%), Rwampara (+69; +31.5%) and Katwa  (+63; +71.6%), while substantial relative increases were observed in Wamba  (+31; +281.8%), Beni (+34; +226.7%), Fataki (+37; +246.7%) and Isiro (+18;  +150.0%). Conversely, cases declined in established transmission foci such as Mongbwalu (−134; −61.5%) and Nizi (−97; −34.8%). Overall, the data indicate a redistribution of transmission, with declining activity in some established hotspots occurring alongside intensification in others and continued geographic expansion into new health zones.

(...)

    Mortality remains high and varies substantial across affected areas. Ituri continues to account for the largest absolute burden, with 1 878 cumulative confirmed deaths, representing 79.0% of all deaths nationally.  However, the CFR is considerably higher in Nord-Kivu (70.5%), than in Ituri  (44.1%) and Haut-Uélé (45.3%). This disparity was also evident during the most  recent 21 days, when Nord-Kivu accounted for only 16.7% of reported cases but  24.0% of reported deaths nationally.

    At health-zone level, the largest numbers of deaths were reported from  major transmission foci in Ituri, particularly Bunia, Rwampara and Mongbwalu.  However, CFRs were substantially higher in several health zones in Nord-Kivu, including, Butembo (85.6%), Beni (75.8%) and Katwa (68.1%), compared  with Bunia (29.8%), Rwampara (38.9%), and Mongbwalu (49.9%). These marked  geographic variation indicate that mortality is not explained by  transmission intensity alone and warrants further assessment of differences in case detection, timeliness of presentation and referral, community  deaths, access to care and clinical management. 

    Mortality remains high both in the community and among patients in treatment facilities. During the past six weeks, an average of approximately 162  community deaths and 98 treatment facility deaths were reported each week. 

    Community deaths accounted for approximately 60% of all confirmed  deaths during this period. The high proportion of community deaths highlights  persistent challenges in early case detection, referral and access to designated  treatment facilities. 

    Mortality among patients reaching treatment facilities may reflect late  presentation and severe disease at admission, while further assessment is needed  to determine the contribution of clinical management capacity, quality of  care and patient vulnerabilities, including age, malnutrition and comorbidities. For  the purposes of this report, community death refers to death occurring outside a  designated Ebola treatment facility, including at home, in the community, or in  another (non-Ebola) health facility.

(...)

    The current BVD outbreak continues to follow a markedly different trajectory from previous major Ebola disease outbreaks. 

    

    During the first 95 days of reporting, the 7-day moving average increased  progressively, reaching more than 90 confirmed cases per day, substantially  higher than the levels observed during comparable period of the 2014 – 2016 

West Africa and 2018 – 2020 Democratic Republic of the Congo outbreaks. 

    With 5 021 confirmed cases reported as of 16 August 2026, this has  become the largest BVD outbreak ever recorded and the second-largest Ebola  disease outbreak on record. 

    The sustained high incidence and continued geographic expansion indicates  that transmission remains intense and that the outbreak has not yet entered a  clear declining phase.

Figure 5. Comparison of three major Ebola disease outbreak trajectories during the first 95 days of reporting using seven-day moving averages of the daily number of confirmed cases reported.

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Uganda and France

    Uganda has now recorded 31 consecutive days without a new confirmed  BVD case since the last patient was discharged on 16 July 2026. All identified  contacts have completed follow-up, with no further cases detected. The continued  high level of transmission in neighbouring eastern Democratic Republic of the  Congo, however, means that the risk of crossborder reintroduction remains.

    France has reported no new confirmed BVD cases for 43 consecutive days  since the imported case was discharged on 4 July 2026. This period is more  than twice the maximum 21-day incubation period for BVD. No secondary  transmission has been detected, and all five identified flight contacts completed  follow-up without developing symptoms.

Risk Assessment

    The risk of further geographic spread within the Democratic Republic of the Congo remains very high, while the risk of cross-border spread remains  elevated. 

    The detection of a case in Buta, Bas-Uélé and additional affected health  zones in Tshopo, together with sustained transmission in highly mobile areas of  Ituri, Nord-Kivu and Haut-Uélé, increases the potential for onward spread along major transport corridors. Tshopo, particularly the Kisangani transport hub, is of 

particular concern because of its connectivity with other parts of the country and  the potential for longer-distance dissemination towards Kinshasa. 

    Continued transmission in eastern and north-eastern Democratic  Republic of the Congo also increases the likelihood of cross-border movements of  infected persons. 

    Uganda, South Sudan and the Central African Republic remain at  particularly high risk of importation, given their geographic proximity to affected 

areas of the Democratic Republic of the Congo, established cross-border population movements and connectivity along major mobility corridors. 

    Enhanced surveillance, information sharing, preparedness and cross- border coordination should therefore be maintained along priority mobility corridors and at points of entry.

(...)

Situation interpretation

    The BVD outbreak is evolving into a more geographically dispersed emergency, with persistent transmission in established hotspots occurring  alongside intensification in other areas and continued seeding of new locations. 

    The combination of very high mortality, substantial deaths outside  designated treatment facilities, increasing surveillance workload and  uneven response capacity suggests that current interventions are not yet  achieving sufficient speed, coverage or intensity to interrupt transmission. 

    The response should therefore be increasingly risk-informed and geographically differentiated, with the intensity and combination of  interventions adapted to local transmission patterns and operational gaps, while  simultaneously establishing sufficient response capacity ahead of transmission in 

newly affected and high-risk areas. 

    Given increasing connectivity between affected areas and major  populationmovement corridors, stronger interprovincial and cross-border  surveillance and preparedness are also critical to prevent further geographic spread.

Source: 

Link: https://www.afro.who.int/countries/democratic-republic-of-congo/publication/ebola-bundibugyo-virus-disease-outbreak-5

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A novel candidate #vaccine virus derived from #Japan's first #mammalian case of clade 2.3.4.4b #H5N1 highly pathogenic avian #influenza virus

 

Abstract

The development of candidate vaccine viruses (CVVs) for pre-pandemic preparedness requires attenuation of pathogenicity while maintaining immunogenicity. In this study, we developed and characterized NIID-002, a reassortant virus derived from A/Ezo red fox/Hokkaido/1/2022 (H5N1; clade 2.3.4.4b), to evaluate its suitability as a candidate vaccine. NIID-002 exhibited markedly reduced pathogenicity compared with its parental strain, while retaining broad antigenic reactivity and protein yield comparable to other clade 2.3.4.4b CVVs. In mammalian models, NIID-002 demonstrated strong attenuation, causing no lethal infection in mice and only minimal weight loss with limited viral replication in ferrets. Antisera raised against NIID-002 reacted broadly with recent wild-type H5N1 isolates, suggesting potential broad protection. Protein yield analysis confirmed a production efficiency comparable to that of other CVVs within the same clade, supporting its feasibility for large-scale vaccine manufacturing. Overall, NIID-002 fulfills the key requirements for the pandemic preparedness of CVV, combining reduced pathogenicity, broad antigenic reactivity, and adequate production efficiency. These findings highlight its potential as a candidate H5N1 vaccine and underscore the continued need for surveillance and refinement of influenza vaccine strategies to address evolving viral threats.

Source: 

Link: https://www.sciencedirect.com/science/article/abs/pii/S0264410X26008571?via%3Dihub

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#Community #engagement strategies for preventing recurrent #Nipah virus #outbreaks in #Bangladesh and #India: adapting a framework for outbreak preparedness and response

 

Abstract

The Nipah virus (NiV) infection is a highly fatal zoonotic disease with pandemic potential which has led to recurrent outbreaks in Bangladesh and India. While transmission pathways, including contaminated date palm sap and human-to-human spread, are increasingly identified, significant uncertainties remain. With no approved therapeutics or vaccines, prevention depends on addressing ecological and behavioural drivers of transmission. This viewpoint draws on selected evidence from NiV outbreaks and response to other zoonotic disease epidemics, such as Ebola, rabies, and the Marburg virus disease, we seek to foster discussion on why community engagement could be central to NiV prevention and preparedness. We highlight the relevance of community engagement through a spectrum of its intensity, which distinguishes between community-oriented, community-based, community-managed, and community-owned approaches. Adapting an existing model, we discuss how community engagement principles can be applied to tackle recurring NiV outbreaks in Bangladesh and India. By aligning interventions with sociocultural realities, community engagement can improve acceptability, enhance early detection, strengthen outbreak response, and support preparedness for future vaccine and therapeutic research. However, evidence specific to NiV remains limited and lessons from other diseases should be applied judiciously. In the absence of medical countermeasures, participatory, locally grounded approaches offer a sustainable pathway to reduce recurrent outbreaks and prevent future spillover events.

Source: 

Link: https://jogh.org/2026/jogh-16-03024

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