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

 

ABSTRACT

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

Source: 

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

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

 

ABSTRACT

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

ClinicalTrials.gov registration: NCT05975840.

Source: 

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

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

 

A flock of backyard laying hens in Bayern Region.

Source: 

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

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

 

    11 June 2026

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

Background

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

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

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

Key findings and recommendations

Risk assessment

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

Recommendations

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

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

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

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

Source: 

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

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

 

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

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

    The virus has been identified as Andes hantavirus.

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

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

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

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

    ° Confirmed cases: 12

    ° Probable cases: 1

    ° Suspected cases: 0

    ° Number of deaths: 3

(...)

Source: 

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

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

 

{Excerpt}

(...)

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

(...)

Source: 

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

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

 

Key Points

    ° Question: 

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

    ° Findings:  

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

    ° Meaning:  

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

Abstract

Importance  

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

Objective  

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

Design, Setting, and Participants  

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

Exposures  

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

Main Outcomes and Measures  

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

Results  

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

Conclusions and Relevance  

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

Source: 

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

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

 

Abstract

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

Competing Interest Statement

The authors have declared no competing interest.

Funder Information Declared

Cornell Feline Health Center, Ithaca, US

Source: 

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

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

 

ABSTRACT

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

Source: 

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

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

 

Highlights

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

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

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

Abstract

Background

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

Methods

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

Results

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

Conclusions

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

Source: 

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

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

 

Latest update

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

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

    This is not a new case.

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

    All necessary public health actions have been carried out. 

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

Source: 

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

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

 

{Excerpt}

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

(...)

Source: 

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

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

 

Abstract

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

Source: 

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

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

 

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

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

Risk statement

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

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

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

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

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

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

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

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

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

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

    To date, 12 patients have recovered. 

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

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

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

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

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

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

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

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

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

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

    The risk globally remains unchanged and is assessed as low.  

    The risk in the Democratic Republic of the Congo remains assessed as very high due to ongoing transmission and the continued expansion of the outbreak into new health zones, increasing the potential for further national and regional spread. 

    The key factors underpinning this assessment include:  

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

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

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

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

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

            o 19 high-risk health zones 

            o 115 at-risk health zones 

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        • Potential for undetected chains of transmission in border communities. 

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

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

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

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

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

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

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

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

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

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

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

(...)

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

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

(...)

Source: 

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

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Egyptian rousette #bat humoral #immunity to #H9 #influenza hemagglutinin

 

Abstract

In mammals, antibodies are central to antiviral defense, but they can also impose selective pressure that drives viral evolution. The interplay between viral antigenic variation and host antibody diversification constitutes a molecular arms race that influences pathogenicity, transmission, and spillover risk. Bats are reservoirs for zoonotic viruses with pandemic potential yet they appear to tolerate infection without overt disease. Although distinctive features of bat innate immunity have been described, the role of adaptive immunity, particularly antibody-mediated responses, remains largely undefined. Moreover, how antibody evolutionary pressure operates in bats is unknown, in part because tools to interrogate bat B cell responses at the monoclonal level are limited. Here, we developed a yeast surface display library of bat antibodies derived from splenic RNA of wild-caught Egyptian rousette bats to interrogate humoral responses to the bat-derived H9 influenza hemagglutinin. We isolated monoclonal antibodies recognizing the hemagglutinin (HA) antigen and defined their gene usage, somatic hypermutation frequency, binding affinities, and breadth. We then used cryo-EM to structurally characterize three bat antibodies in complex with HA engaging distinct antigenic sites. Together, these data enable direct comparison with human anti-influenza antibodies highlighting similarities in humoral immunity across mammals and provides a tool to examine bat antibody responses to other potential zoonotic viruses.

Competing Interest Statement

The authors have declared no competing interest.

Source: 

Link: https://www.biorxiv.org/content/10.64898/2026.06.04.730146v1

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Avian #Influenza #Report - May 31 – June 6 '26 (Wk 23) (#HK CHP, June 9 '26): 2 new human #H5N1 virus cases in #Bangladesh, #India; 1 new case of H9N2 virus in #China

(...)

    -- Bangladesh

        ° Avian influenza A(H5N1) 

            ° Sylhet Division: 

                - The case involved a child with symptom onset on March 27, 2026.  

                - The patient was admitted to a hospital on March 28 for treatment of measles with bronchopneumonia, and was discharged on March 30. 

                - Epidemiological investigations revealed the case had exposure to household poultry.   

                - No additional cases were reported among the identified contacts.  

    -- India

        ° Avian influenza A(H5N1)

            - The case involved a child who developed symptoms and was admitted to a hospital on March 19, 2026. 

            - The patient was discharged on March 23.  

            - Epidemiological investigations revealed the case likely had indirect exposure to poultry. 

            - No additional cases were reported among the identified contacts. 

        -- China

            ° Avian influenza A(H9N2): 

                ° Yunnan Province: 

                    - A 4-year-old boy with onset on May 17, 2026. 

(...)

Link: https://www.chp.gov.hk/files/pdf/2026_avian_influenza_report_vol22_wk23.pdf

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#Honduras - #Influenza A #H5 viruses of high pathogenicity (Inf. with) (non-poultry including wild birds) (2017-) - Immediate notification

 

{Click on Image to Enlarge}

By Charles J. Sharp - Own work, from Sharp Photography, sharpphotography.co.uk, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=129540572

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    On June 3, 2026, the Regional Office of the National Agri-Food Health and Safety Services (SENASA) was notified of an unusual mortality event among wild birds in the community of El Higuito, Talgua, in the department of Lempira, an area bordering the department of Copán. 

    Following the official reception of the notification and the collection of samples, the Central Laboratory (IHIMV) confirmed on June 5, 2026, via RT-PCR, the presence of Avian Influenza Type A Subtype H5. 

    The event involved the mortality of black vultures (Coragyps atratus), which poses a potential risk to small-scale and commercial poultry farming in the area. 

    As an immediate response, the contingency team was activated, carrying out the collection, incineration, and sanitary burial of 136 wild birds found dead, with the aim of reducing the environmental viral load and limiting the spread of the pathogen. 

    Additionally, coordination with poultry sector authorities was strengthened to implement preventive and biosecurity measures. 

    Epidemiological surveillance has been intensified both in the outbreak zone of the event and around the outbreak. 

    Through door-to-door monitoring conducted in six surrounding communities, 14,282 backyard birds were inspected without identifying clinical signs compatible with avian influenza or mortality events. 

    These findings indicate that, to date, there is no evidence of transmission to domestic poultry. 

    Given the epidemiological risk associated with the circulation of the virus in wildlife, active surveillance will continue in neighbouring communities and municipalities, along with the strengthening of biosecurity measures and risk communication directed at producers and the general public. 

    Follow-up reports will be submitted to provide periodic updates.

Source: 

Link: https://wahis.woah.org/#/in-review/7612

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Could #bradykinin #pathway inhibition change the course of severe #hantavirus disease?

 

Highlights

    • Hantavirus triggers the kallikrein–kinin system, driving severe capillary leak.

    • In vitro data show that bradykinin directly disrupts endothelial barrier function.

    • Two clinical cases support targeting the bradykinin pathway with icatibant.

Abstract

A recent multi-country hantavirus outbreak associated with a cruise ship underscores the urgent need to understand the mechanisms driving severe vascular leakage and multi-organ failure. While disease severity is largely attributed to a dysregulated host immune response and intense cytokine surge, the precise molecular mediators remain incompletely defined. Laboratory evidence indicates that hantavirus infection activates the factor XII–dependent kallikrein–kinin system, leading to elevated bradykinin production and subsequent endothelial barrier dysfunction. This translational mechanism is tentatively supported by two clinical case reports where severe hantavirus infections were successfully treated with the bradykinin receptor antagonist icatibant. We hypothesize that exaggerated bradykinin signalling drives the vascular leak phenotype, making the kallikrein–kinin pathway a compelling therapeutic target. Ultimately, effectively combating hantavirus-induced vascular permeability may require a multi-faceted approach combining targeted bradykinin inhibition with broader immunomodulatory strategies.

Source: 

Link: https://www.sciencedirect.com/science/article/abs/pii/S016524782600074X?via%3Dihub

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#Taiwan reported a rise in domestic #COVID19 cases, public is invited to wear masks as needed (CDC, June 9 '26)

 

    The Taiwan Centers for Disease Control (CDC) stated today (June 9th) that, according to monitoring data, the domestic COVID-19 epidemic has been rising from its low point. 

    In the 22nd week (May 31st - June 6th), there were 1,000 outpatient and emergency room visits related to COVID-19, a 4.1% increase compared to the previous week. 

    Last week (June 2nd - June 8th), there were 5 new local cases of severe COVID-19 complications, with no new local deaths. 

    Since October 2025, there have been a cumulative total of 90 local cases of severe COVID-19 complications, of which 14 have died. 

    The majority of severe cases are among those aged 65 and above (72.2%) and those with a history of chronic diseases (81.1%), and 93.3% have not received the COVID-19 vaccine this season.

    The Centers for Disease Control (CDC) pointed out that the global COVID-19 positivity rate has recently risen slightly from its low point. 

    The predominant circulating variants are BA.3.2 and XFG, followed by NB.1.8.1. 

    Among all regions, Southeast Asia has seen a significant increase. 

    The epidemic in neighboring countries is rising in India, the epidemic in Singapore is fluctuating from its peak, the epidemic in China is rising slightly from its low point, and the epidemic in Japan is flat from its low point.

    The Taiwan Centers for Disease Control (CDC) reminds the public that with the rise of COVID-19 cases in Taiwan, it urges the public to strengthen their self-protection awareness, practice hand hygiene and respiratory etiquette. 

    To protect their own health and the health of others, if they experience respiratory symptoms such as fever, cough, runny nose, or sore throat, or when visiting healthcare facilities, in crowded places where social distancing is difficult or poorly ventilated, or in close contact with the elderly or immunocompromised individuals, it is recommended to wear a mask. 

    If you have a fever or respiratory symptoms, it is advised to stay home and avoid unnecessary outings. 

    Those with severe risk factors and who meet the criteria for publicly funded antiviral medication should seek medical attention as soon as possible if they experience suspected symptoms. 

    A doctor will assess the symptoms and prescribe antiviral medication to reduce the risk of serious complications or death after infection. 

    Furthermore, the CDC urges those who have not yet received this season's COVID-19 vaccine within the past six months to get vaccinated as soon as possible.

    The Centers for Disease Control (CDC) emphasizes that there are currently sufficient reserves of COVID-19 vaccines and antiviral drugs. 

    For inquiries about vaccination sites, contracted hospitals for publicly funded oral antiviral drugs, and the latest epidemic prevention policies, the public can visit the CDC website (https://www.cdc.gov.tw) or call the toll-free epidemic prevention hotline 1922 (or 0800-001922).

Source: 

Link: https://www.cdc.gov.tw/Bulletin/Detail/gyc9j6zazoe_7nR9FqdFYQ?typeid=9

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