#Influenza at the #human - #animal #interface - #Summary and #risk #assessment, from 1 April to 8 May 2026{1} (#WHO, June 5 '26)

 

New human cases{2}: 

    ° From 1 April to 8 May 2026, based on reporting date, detections of influenza A(H5N1) in three humans, influenza A(H5N6) in one human, influenza A(H9N2) in five humans, and influenza A(H1N2) variant ((H1N2)v) virus in one human were reported officially. 

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}: 

    ° Sustained human to human transmission has not been reported 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 remains low. 

    ° 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  

    ° On 23 April 2026, Bangladesh notified WHO of one laboratory-confirmed human case of avian influenza A(H5) infection in a child from Sylhet Division. 

    ° The patient developed fever and cough on 27 March 2026 and was admitted to hospital on 28 March with a clinical diagnosis of measles with bronchopneumonia. 

    ° As part of hospital-based influenza surveillance, a sample was collected on 29 March and received by the Institute of Epidemiology, Disease Control and Research (IEDCR) on 20 April. 

    ° The sample tested positive for influenza A(H5N1) on the same day by real-time reverse transcription polymerase chain reaction (RT-PCR). 

    ° The patient was discharged on 30 March. 

    ° No additional cases were reported among identified contacts. 

    ° Epidemiological investigations identified exposure to household poultry.  

    ° This is the second laboratory-confirmed human case of avian influenza A(H5N1) reported in Bangladesh in 2026. 

A(H5N1), Cambodia 

    ° On 22 April 2026, Cambodia notified WHO of one laboratory-confirmed human case of avian influenza A(H5) infection in a 66-year-old woman with comorbidities from Svay Rieng province. 

    ° The patient developed symptoms on 15 April 2026 and was admitted to district hospital on 16 April and provincial hospital the next day. 

    ° As part of severe acute respiratory infection surveillance, a sample was collected on 17 April and received by the National Institute of Public Health on 21 April. 

    ° The sample tested positive for influenza A(H5N1) on the same day by real-time RT-PCR, and the result was confirmed by Institut Pasteur du Cambodge on 22 April. 

    ° The patient died on 22 April. 

    ° No additional cases were reported among 15 identified contacts. 

    ° Epidemiological investigations identified exposure to sick and dead household chickens prior to illness onset.  

    ° Four human infections with A(H5N1) viruses have been confirmed in Cambodia in 2026, including one fatal case. 

    ° Influenza A(H5N1) viruses continue to be detected in domestic birds in Cambodia in 2026, including in areas where human cases have been detected. 

    ° Where the information is available, the genetic sequence data from the viruses from the human cases closely matches that from recent local animal viruses and are identified as clade 2.3.2.1e viruses. 

    ° From the information available thus far on these recent human cases, there is no indication of human-to-human transmission of the A(H5N1) viruses.   

A(H5N1), India 

    ° On 27 March 2026, India notified WHO of one laboratory-confirmed human case of avian influenza A(H5N1) infection in a child from West Bengal state. 

    ° The patient developed fever and cough and was admitted to hospital on 19 March. 

    ° The patient was discharged on 23 March. 

    ° Laboratory testing at the Indian Council of Medical Research (ICMR) National Institute of Virology in Pune confirmed influenza A(H5N1). 

    ° Genomic sequencing identified the virus as belonging to clade 2.3.2.1a, closely related to strains previously reported from Bangladesh and India in 2025. 

    ° No additional cases were reported among identified contacts. 

    ° Epidemiological investigations identified likely indirect exposure to poultry.  

    ° This is the first laboratory-confirmed human case of avian influenza A(H5N1) reported in India in 2026. 

A(H5N6), China 

    ° On 29 April 2026, China notified WHO of one laboratory-confirmed human case of avian influenza A(H5N6) infection in a 55-year-old female with comorbidities from Chongqing Municipality. 

    ° She had onset of symptoms on 16 April 2026 and was hospitalized on 23 April with severe pneumonia.  

    ° The patient died on 3 May 2026. 

    ° She had slaughtered and prepared poultry prior to onset of symptoms. 

    ° Environmental samples collected from the food preparation tools at the patient’s residence tested positive for influenza A(H5). 

    ° No further cases were detected among contacts of the patient. 

    ° This is the first laboratory-confirmed human case of infection with an A(H5N6) virus detected since 2024. 

    According to reports received by WOAH, various influenza A(H5) subtypes continue to be detected in wild and domestic birds in Africa, the Americas, Asia and Europe. 

    Infections in non-human mammals are also reported, including in marine and land mammals.{7} 

    A list of bird and mammalian species affected by HPAI A(H5) viruses is maintained by FAO.{8}   

Risk assessment for avian influenza A(H5) viruses:   

    1. What is the current global public health risk of additional human cases of infection with avian influenza A(H5) viruses?   

        ° Most human infections so far have been reported in people exposed to A(H5) 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(H5) 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(H5) 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(H5) 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(H5) 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 April and 6 May 2026, China notified WHO of five laboratory-confirmed cases of A(H9N2) virus infection. 

    ° The first case had comorbidities and developed severe pneumonia. 

    ° All the cases except the child from Jiangxi had exposure to live bird markets or household birds. 

    ° Samples from environments associated with the likely area of exposure of some of these 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.  

Swine influenza viruses in humans  

Influenza A(H1N2)v, United States  

    ° On 2 May 2026, the United States notified WHO of a laboratory-confirmed case of A(H1N2)v influenza virus infection in an individual under 18 years of age from Nebraska. 

    ° The patient had onset of mild illness in early April 2026 and has recovered. 

    ° A respiratory specimen collected in mid-April as part of routine surveillance was sent to the US Centers for Disease Control and Prevention (CDC). 

    ° Real-time RT-PCR testing by CDC determined the sample was positive for an influenza A(H1N2)v virus. 

    ° Additional genetic and virologic characterization is currently underway. 

    ° Local public health investigations did not identify direct or indirect exposure to swine. 

    ° One household contact had mild respiratory illness also in early April but no additional cases of A(H1N2)v were identified at the time of reporting.{9} 

    ° This is the first human A(H1N2)v infection detected in the United States in 2026.  

Risk assessment for swine influenza viruses:   

    1. What is the public health risk of additional human cases of infection with swine influenza viruses?   

        ° Swine influenza viruses circulate in swine populations in many regions of the world. 

        ° Depending on geographic location, the genetic characteristics of these viruses differ. 

        ° Most human cases are exposed to swine influenza viruses through contact with infected animals or contaminated environments. 

        ° Human infection tends to result in mild clinical illness in most cases. 

        ° Since these viruses continue to be detected in swine populations, further human cases are expected. 

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

        ° The overall risk of additional sporadic human cases is low.   

    2. What is the likelihood of sustained human-to-human transmission of swine influenza viruses?    

        ° No sustained human-to-human transmission was identified associated with the event described above. 

        ° Current evidence suggests that contemporary swine influenza viruses have not acquired the ability of sustained transmission among humans.  

    3. What is the likelihood of international spread of swine influenza 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 community level spread is considered unlikely as current evidence suggests that these viruses have 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.{10} 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).{11,12} State Parties to the IHR (2005) are required to immediately notify WHO of any laboratory-confirmed{13} case of a recent human infection caused by an influenza A virus with the potential to cause a pandemic{14}. 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{15} 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/ 

(...)

{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 (WOAH). Avian influenza. Global situation. Available at: https://www.woah.org/en/disease/avian-influenza/#ui-id-2. 

{8} Food and Agriculture Organization of the United Nations. Global Avian Influenza Viruses with Zoonotic Potential situation update. Available at: https://www.fao.org/animal-health/situation-updates/global-aiv-withzoonotic-potential/bird-species-affected-by-h5nx-hpai/en. 

{9} US CDC. FluView week 17, 8 May 2026 (https://www.cdc.gov/fluview/surveillance/2026-week-17.html). 

{10} 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/). 

{11} 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_20142022-2024-en.pdf). 

{12} 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)). 

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

{14} 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). 

{15} 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--8-may-2026

____

#Hantavirus #outbreak on a cruise #ship in the South Atlantic

 

{Excerpt}

On May 2, 2026, a cluster of severe respiratory illness among passengers aboard a cruise ship in the Atlantic was reported to WHO, and a suspected hantavirus outbreak was identified. The vessel departed from Ushuaia, Argentina, on April 1, 2026, carrying 147 individuals (88 passengers and 59 crew members) from 23 countries.1 This event raises concerns about surveillance, outbreak response, containment, and the potential for international spread of hantavirus. As of May 4, 2026, seven cases (two laboratory confirmed and five suspected) have been identified, including three deaths, corresponding to a crude case-fatality rate of more than 40%.1 All patients presented with fever or gastrointestinal symptoms, or both, with rapid progression to pneumonia, acute respiratory distress syndrome, and shock in severe cases.1 The overall attack rate was 4·8% (seven of 147 individuals on board infected).1

(...)

Source: 

Link: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(26)00934-7/fulltext?rss=yes

____

Cruise #ship #hantavirus #outbreak in remote #island communities

 

On April 27, 2026, the Dutch-flagged expedition cruise ship MV Hondius arrived at Ascension Island, a remote mid-Atlantic UK Overseas Territory (UKOT). The vessel had left Ushuaia (Argentina) on April 1, 2026, then visited the Antarctic Peninsula and other UKOT islands in the south Atlantic: the British Antarctic Territory, South Georgia, Tristan da Cunha, and St Helena (figure).1 At Ascension Island, a 69-year-old man (case 3) with a severe respiratory syndrome was admitted into the care of the island's small medical team. This team resuscitated the patient and arranged for a medical evacuation service in South Africa to transfer him to intensive care in Johannesburg. 

(...)

Source: 

Link: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(26)01014-7/fulltext?rss=yes

____

#SARS-CoV-2 #Omicron BA.2.86 and JN.1 expand #tropism in #human proximal #intestinal epithelium

 

Abstract

Omicron SARS-CoV-2 has diversified into multiple sub-lineages, complicating assessment of their intrinsic phenotypes due to background population immunity. We compare replication and biological characteristics of variants from BA.1 to JN.1 using human bronchial and lung explants, airway organoids, colon cells, and proximal intestinal enteroids. XBB.1.5 and EG.5.1 achieve higher replication titres in respiratory tissues than BA.2.86 and JN.1, indicating enhanced respiratory fitness. EG.5.1 displays dual cell-entry pathways and greater replication in alveolar epithelial cells, supporting increased lung tropism and pathogenicity. In contrast, BA.2.86 and JN.1 rely on TMPRSS2-mediated entry in airways. Notably, BA.2.86 and JN.1 replicate more efficiently than EG.5.1 in proximal intestinal enteroids in an ACE2- and TMPRSS2-dependent manner, but not in colon cells. JN.1 exhibits elevated intestinal tropism with limited proinflammatory cytokine induction, suggesting potential for faecal transmission. Here we show XBB.1.5 and EG.5.1 greater transmissibility and severity potential whereas BA.2.86 and JN.1 exhibit enhanced intestinal adaptation.

Source: 

Link: https://www.nature.com/articles/s41467-026-74111-y

____

Broad heterologous #protection against #Influenza A viruses by an adjuvant-free modular mucosal T-cell #vaccine #platform

 

Abstract

Rapid antigenic evolution of Influenza A viruses (IAVs) enables their escape from strain-specific vaccine immunity, underscoring the need for broadly protective strategies. Here, we describe a modular, adjuvant-free mucosal vaccine platform that elicits potent and cross-protective T cell immunity. The approach uses overlapping CD4+ and CD8+ epitope-dense regions from the consensus IAV M1 and NP proteins, identified through computational and functional screening. These peptides are delivered using polylactic-co-glycolic acid (PLGA) microparticles, engineered for selective uptake by antigen-presenting cells and enabling sustained, pH-responsive antigen release. This design enhances antigen processing and MHC cross-presentation, functionally substituting for a conventional adjuvant. This formulation drives robust activation of primed human as well as murine CD4+ and CD8+ T cells and confers broad protection against homologous (H1N1, H3N2) as well as heterologous (H5N1) IAV strains in immunized mice. Overall, this adjuvant-free dose-sparing platform establishes an adaptable framework for next-generation broadly-protective vaccines against rapidly evolving viruses.

Competing Interest Statement

R.T.Y. and S.T. are co-inventors on an unpublished patent titled Immunogenic peptide(s), composition(s) and application(s) thereof broadly protective against Influenza, Indian patent application number 202541082426. The other authors declare that they have no competing interests.

Funder Information Declared

DBT-ENDFLU, BT/IN/EU-INF/15/RV/19-20

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.03.29.715080v2

____

#Spain, Health authorities have established #criteria for #hospital discharge and follow-up for confirmed cases of #hantavirus (June 4 '26)

 

    Madrid, June 4, 2026 

    The Ministry of Health has updated the protocol for managing people affected by the Andes hantavirus outbreak associated with the MV Hondius cruise ship, establishing the clinical and microbiological criteria that will allow hospital discharge of confirmed cases and the conditions for the completion of contact tracing.

    According to the protocol approved by the Public Health Commission, people diagnosed with Andes hantavirus infection who remain admitted to a High Level Isolation and Treatment Unit (UATAN) may be discharged from the hospital once clinical recovery has been achieved, for which they must have remained at least three days without symptoms compatible with the disease and obtain two negative results in PCR tests performed on urine and oropharyngeal exudate, separated by a minimum interval of 48 hours.

    The most recent studies on Andes virus show that viral RNA can be detected in blood for an extended period after clinical recovery. 

    For this reason, discharge criteria are not based solely on a negative blood PCR test, but also on the absence of symptoms and negative results in biological samples most directly related to possible viral shedding, such as urine and oropharyngeal swabs.

    Consequently, the protocol expressly acknowledges that some individuals may continue to test positive for COVID-19 via PCR in their blood after hospital discharge. 

    Available scientific evidence indicates that this persistence of viral genetic material can continue after clinical recovery, without posing a risk of disease transmission. 

    In these cases, they will remain under clinical follow-up for six months to monitor their progress, detect any potential long-term effects, and undergo regular check-ups until the test is negative.

    Those being monitored as contacts must complete the maximum quarantine period established by the protocol. 

    If they remain asymptomatic throughout the home monitoring period, a sample will be taken at the end of this period and analyzed by the National Microbiology Center. 

    Only after obtaining a negative result will they be able to end the monitoring measures and fully resume their normal activities.

    These measures are part of the surveillance and control system designed to ensure the safety of patients, healthcare professionals and the general population, applying the precautionary principle while international monitoring of this outbreak continues.

Source: 

Link: https://www.sanidad.gob.es/gabinete/notasPrensa.do?id=6928

____

#Scenario #analysis for potential #community spread of #Andes virus (ANDV)

 

Abstract

We simulated the potential community spread of Andes virus (ANDV) following the introduction of a single infectious individual in a generic population, based on epidemiological parameters derived from a human-to-human historical outbreak. Under current available evidence, our analyses suggest that, within 4 months from the index case’s symptom onset, the expected outbreak size is unlikely to exceed 50 cases, with a high probability of epidemic extinction, particularly when > 50% cases are effectively isolated from the start of the outbreak.

Source: 

Link: https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2026.31.22.2600425#abstract_content

____

Why #Andes #hantavirus is not the next #SARS-CoV-2: contrasting viral shedding, #transmissibility and #genomic patterns

 

Abstract

A cruise ship-associated Andes hantavirus outbreak has raised questions usually associated with respiratory viruses, including transmissibility and pandemic risk. Although Andes virus may enter through the respiratory route, cause severe respiratory disease and under close contact spread between humans, it differs fundamentally from SARS-CoV-2. The ecology is rodent-borne, pathogenesis is vascular, diagnosis is centred on blood PCR and serology, and genetic diversity is mainly shaped by reservoir ecology and geography rather than by sustained human-to-human transmission and immune selection.

Source: 

Link: https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2026.31.22.2600428?emailalert=true#abstract_content

____

Use of #tocilizumab for severe #hantavirus pulmonary syndrome: a MEURI case series with contextual comparisons

 

Summary

Background

Hantavirus pulmonary syndrome is a rare zoonotic disease associated with high mortality, acute respiratory failure, shock, capillary leak, and systemic inflammation. Currently, no specific antiviral or immunomodulatory therapy has proven effective for routine clinical use. The current cruise-associated hantavirus outbreak motivated this early descriptive report from an ongoing, larger, pre–post study (ISRCTN72088243). We aimed to describe tocilizumab use under the Monitored Emergency Use of Unregistered and Investigational Interventions (MEURI) framework.

Methods

In this descriptive case series at Hospital Zonal de Bariloche Dr Ramón Carrillo, San Carlos de Bariloche, Argentina, patients with laboratory-confirmed severe hantavirus pulmonary syndrome and requiring intensive care unit (ICU) admission or assessment were eligible to receive tocilizumab in addition to standard supportive care, in accordance with the MEURI framework. Tocilizumab was administered to patients within 24 h of ICU admission or ICU-level evaluation as a single intravenous dose of 8 mg/kg, up to a maximum of 800 mg. During this time, five eligible patients could not receive tocilizumab because timely administration was not feasible due to drug unavailability or refractory shock at diagnosis. This case series represents the first report from the larger, ongoing, pre–post study (ISRCTN72088243). The main descriptive outcome was survival to ICU discharge in patients who received tocilizumab and patients who were eligible to receive tocilizumab but did not.

Findings

Between June 1, 2024, and May 5, 2026, 13 patients with laboratory-confirmed hantavirus pulmonary syndrome were evaluated for inclusion after institutional approval of the MEURI protocol. Ten met eligibility criteria for tocilizumab; five received tocilizumab and five did not. In the five eligible non-treated patients, two were diagnosed when they were already in refractory shock, precluding timely administration, and three did not receive tocilizumab because the drug was unavailable when treatment was being considered. Four of five tocilizumab-treated patients survived to ICU discharge. The fifth treated patient died after rapid progression to refractory shock. All five eligible non-treated patients died after ICU admission.

Interpretation

These observations suggest that IL-6 inhibition warrants further evaluation within the MEURI framework or analogous expanded-access frameworks, and, when feasible, collaborative randomised studies with standardised data collection.

Funding

None.

Translations

For the Spanish translations of the abstract see Supplementary Materials section.

Source: 

Link: https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(26)00285-9/abstract

____

Breeding #pig #transport drives the dispersal of #swine #influenza A virus across #Europe

 

Abstract

Pigs serve as reservoirs of former human influenza A virus (IAV) H1N1 and H3N2 lineages and act as mixing vessels for diverse strains, facilitating the emergence of novel IAVs. Understanding the spread and evolution of swine IAVs (swIAVs) is therefore crucial to assess the risk of strains with zoonotic potential emerging. This study uses a phylogeographic framework to investigate the predictors of swIAV dispersal across Europe. All publicly available swIAV genomic sequences were retrieved and subsampled for the ten largest European pig-producing countries. Discrete phylogeographic reconstructions were conducted for H1, H3, N1, N2 encoding genes and all internal gene segments. Our analyses indicate that viral dispersal predominantly occurred from north-western to southern and eastern Europe, with frequent long-distance transitions between non-adjacent countries. We also extended the discrete phylogeographical analyses with generalized linear models to test the association between viral movement and potential predictors, such as live pig trade, pork trade, pig densities, farm sizes, or the geographic distance between key pig production zones. We find that breeding pig trade is the only consistently well-supported predictor of between-country transition events, whereas pork trade and geographic distance were not supported. This highlights that farms importing breeding pigs from multiple countries could act as hotspots for reassortment of diverse swIAV strains. Strengthening external biosecurity on farms with emphasis on quarantining breeding pigs, limiting long-distance transport, and implementing a One Health surveillance system for earlier detection of emerging strains, could help curb the rapid spread and evolution of swIAV in Europe.

Competing Interest Statement

The authors have declared no competing interest.

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.06.01.729471v1

____

CEIRR #Risk #Assessment Pipeline executive reports on #H5N1 highly pathogenic avian influenza 2.3.4.4b, swine H1 1B.2, and #H9N2 low pathogenicity avian influenza B4.7.2

 

ABSTRACT

The Centers of Excellence for Influenza Research and Response (CEIRR) Risk Assessment Pipeline (RAP) integrates surveillance, phenotypic analysis, and computational modeling across six CEIRR centers to evaluate the pandemic potential of influenza A viruses. By generating coordinated data sets from wild and domestic animals and linking them to viral evolution and functional traits, CEIRR RAP supports the Centers for Disease Control and Prevention’s and the World Health Organization’s risk-assessment efforts. The RAP’s data packages thereby enable evidence-based prioritization of global influenza preparedness and response strategies.

Source: 

Link: https://journals.asm.org/doi/10.1128/jvi.00545-26

____

Identification and characterization of a #SARS-CoV-2 #Mpro G23 deletion #ensitrelvir - #resistant mutant

 

ABSTRACT

Ensitrelvir is an antiviral drug that specifically targets the conserved main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, mutations in Mpro could confer resistance to antivirals, including ensitrelvir. Thus, identifying SARS-CoV-2 drug-resistant mutants and elucidating their mechanisms of resistance are critical for guiding the selection of effective antiviral therapies. Here, we utilized a recombinant luminescent attenuated SARS-CoV-2 lacking the open reading frames (ORF) 3a and 7b proteins (Δ3a7b-Nluc WT) to safely identify ensitrelvir drug-resistant mutants (DRM-E) without the need of using virulent forms of SARS-CoV-2. We isolated a DRM-E containing a Mpro G23 deletion (G23del) with high resistance (~1,000-fold) to ensitrelvir, but not to the Mpro inhibitor nirmatrelvir or to the RNA-dependent RNA polymerase (RdRp) inhibitor remdesivir. The contribution of G23del in ensitrelvir resistance was confirmed by generating a Δ3a7b-Nluc containing G23del in Mpro (Δ3a7b-Nluc G23del). Δ3a7b-Nluc G23del exhibited resistance to ensitrelvir in both cultured cells and in K18 hACE2 transgenic mice. Binding affinity revealed that the G23del mutation altered ensitrelvir, but not nirmatrelvir, binding to Mpro. Notably, while Δ3a7b-Nluc G23del was affected in viral fitness, serial passage of Δ3a7b-Nluc G23del in the absence of ensitrelvir resulted in the emergence of substitution L50F in Mpro that restored viral fitness loss caused by G23del without altering resistance to ensitrelvir. Our results demonstrate that G23del in Mpro can confer resistance to ensitrelvir. Positively, G23del in Mpro does not render SARS-CoV-2 resistant to nirmatrelvir or remdesivir, suggesting the feasibility of treating SARS-CoV-2 infections containing G23del Mpro with other approved antivirals.

Source: 

Link: https://journals.asm.org/doi/10.1128/mbio.00584-26

____

#Human #MERS-CoV #research in the #Gulf Cooperation Council Countries: A mapping scoping review of #epidemiology, #clade, and research priority gaps

 

Abstract

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) continues to pose a substantial public health challenge within Gulf Cooperation Council (GCC) countries. This scoping review systematically examines geographic distribution, methodological characteristics, and thematic priorities of published research, while identifying critical evidence gaps. A total of 171 peer-reviewed studies on human MERS-CoV were included, with a marked predominance from Saudi Arabia (88.3%). Research output peaked in 2016 and 2019, followed by a decline coinciding with the COVID-19 pandemic. Cross-sectional designs were most common (43.3%), with widespread reliance on non-probability sampling (95.3%). Epidemiology and surveillance constituted the primary research focus (∼24%), with case fatality rate being the most frequently reported metric (43.9%). Limited genomic investigations were identified, with Clade B representing 71.4% of characterized strains. Overall, the evidence base reflects geographic concentration, methodological heterogeneity, and thematic limitations, underscoring the need for expanded research scope and enhanced regional collaboration.

Source: 

Link: https://www.sciencedirect.com/science/article/pii/S1876034126001449?via%3Dihub

____

#Senegal - High pathogenicity avian #influenza #H5N1 viruses (Inf. with) (#poultry) - Immediate notification

 

The farm is part of mixed-species premises with several types of animals, including ducks, broiler chickens, Goliath chickens, and rabbits. Two male breeding ducks were purchased at the Passy market on May 8, 2026, in the department of Foundiougne, located in the Fatick region, to restock the flock and ensure mating with the females. One of the newly introduced adult males died from the disease, while the other survived. The quarantine period for the two new ducks was not applied properly. The first symptoms appeared on May 11, 2026, and the first deaths occurred on May 12, 2026. In total, among the ducks, 29 deaths were recorded out of a flock of 50, representing a mortality rate of 58%. As for the Goliath chickens, out of a flock of 11, 4 deaths were recorded, representing a mortality rate of 36.36%. Additionally, 7 other birds were culled by the manager following the appearance of clinical signs.

Source: 

Link: https://wahis.woah.org/#/in-review/7593

____

#WHO DG's opening #remarks at the media #briefing on the #Bundibugyo Ebola #outbreak – 3 June 2026 (Edited): 344 confirmed cases in #DRC, 15 in #Uganda

 

    Good afternoon to everyone in the room, and good morning, good afternoon and good evening to those joining us online.

    Yesterday I returned from a visit to the Democratic Republic of the Congo, including to the epicentre of the Ebola outbreak in the province of Ituri.

    I met with political leaders, senior health officials, Ambassadors, partners, WHO colleagues, frontline responders, community and faith leaders, women’s groups, business leaders, traditional healers and more.

    I’m very encouraged by the level of commitment I saw everywhere I went. What I saw gave me hope, although challenges remain.

    In DRC, 344 cases have been confirmed, including 60 deaths, in 24 health zones across three different provinces: Ituri, North Kivu and South Kivu.

    The number of suspected cases has now been reduced to 116 from over 1000 last week, as we work through the backlog, either confirming them or ruling them out.

    In Uganda, there is one confirmed death and 15 confirmed cases, including a Congolese resident who travelled to the United Arab Emirates, and then to Uganda.

    WHO is working with public health authorities in Uganda and the UAE to gather additional information, assess the risk of exposure during travel, and to facilitate contact tracing.

    We thank both the UAE and Uganda for their collaboration to mitigate the risks related to this case.

    In addition, a U.S. citizen who was infected in DRC is still receiving care in Germany.

    WHO’s risk assessment remains unchanged: very high at the national level, high at the regional level, and low at the global level.

    The outbreak had a big head start, and we’re still behind, but under the leadership of the Government of DRC, we are catching up.

    In Bunia there are now three treatment centres with a capacity of 80 beds, and there are also treatment units in Mongbwalu, Rwampara, Beni, Goma and Bukavu, and more are on the way.

    So far, six people have recovered in DRC and two in Uganda, showing that people can survive Ebola if they have access to care and go to health facilities as soon as they show symptoms.

    But we still face several challenges.

    First, testing.

    One of our key priorities is to scale up laboratory and diagnostic capacity, to reduce delays in case confirmation and support faster response decisions.

    Accordingly, we are working to decentralize laboratory and diagnostic capacity in priority locations, including Mongbwalu, Beni, Aru, Nyakunde, and Tchomia.

    We also need to scale up readiness, including surveillance, laboratory diagnostics and access to health services in neighbouring provinces and countries.

    Second, contact tracing in the DRC is not yet where it needs to be.

    Only about 45% of contacts have been followed up, and to get ahead of the outbreak we need to get that number up to above 90%.

    Insecurity, displacement and mobile populations make contact tracing especially difficult.

    Third, blanket travel restrictions imposed by some countries are disrupting supply chains and hindering the response.

    WHO recommends exit screening at airports, ports and border crossings to prevent the exportation of cases and contacts.

    We ask countries that have imposed blanket travel restrictions to lift them.

    Fourth, community mistrust is a serious barrier. Some community leaders told me that they believe Ebola is not real.

    Building trust with the communities is therefore critical to bringing the outbreak under control.

    And fifth, as you know, we are fighting this outbreak without vaccines or therapeutics.

    WHO and partners are working on advancing clinical trials as quickly as possible.

    Today, I convened for the second time the principals of the interim Medical Countermeasures Network to align on three priorities:

        ° First, increasing support for decentralized diagnostics;

        ° Second, mobilizing immediate support for the affected countries to lead clinical trials, in cooperation with communities;

        ° And third, accelerating the investments to support all pillars of the response.

    Although vaccines and therapeutics would be a big help, the key to ending this outbreak is not biomedical.

    It’s leadership, ownership, partnership and trust:

        ° Government leadership;

        ° Community ownership;

        ° Strong partnership between the many actors involved, working with one budget, one plan and one report;

        ° And building trust in the affected communities.

    We also need to remember that Ebola is only one health threat among many that these communities face.

    One of the things I heard from the community leaders is that they worry that the response to Ebola may take resources away from the health and humanitarian services they rely on for their many other needs.

    Our ultimate measure of success is not whether we stop this outbreak.

    We will. The Government of DRC has extensive experience with Ebola, and has stopped 16 previous outbreaks.

    It’s just a matter of how quickly we can do it.

    The real measure of success is what we do to prevent the 18th outbreak, and the 19th.

    If the people of Ituri survive Ebola only to die from malaria or malnutrition, or pneumonia or diarrheal disease or HIV or diabetes, we have not really helped them.

    For now, WHO and our partners are committed to ending this outbreak, under the leadership of the government.

    And when it does end, we will remain equally committed to supporting the government and the local communities to build the health and humanitarian services they need and deserve.

    Amna, back to you.

Source: 

Link: https://www.who.int/news-room/speeches/item/who-director-general-s-opening-remarks-at-the-media-briefing---3-june-2026

____