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

 

A poultry farm in Thüringen Region.

Source: WOAH, https://wahis.woah.org/#/in-review/6844

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

 

According to article 10.4.1.4 of the Terrestrial Animal Health Code, Member Countries should not impose bans on the trade in poultry commodities in response to notification on the presence of any influenza A virus in birds other than poultry.

A wild black-headed gull in Vordingborg. 

Source: WOAH, https://wahis.woah.org/#/in-review/6846

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Protective efficacy of the UniFluVec #influenza #vaccine vector against the highly pathogenic influenza A/Indonesia/5/2005 #H5N1 strain in #ferrets

 

Highlights

• UniFluVec, an H1N1pdm vaccine candidate, includes NS1 and NEP modifications to boost attenuation and immunity.

• UniFluVec protects ferrets from H5N1, enhancing clearance, limiting lung damage, and ensuring 100 % survival after one dose.

• Replication-deficient UniFluVec shows cross-protection, supporting its potential as a pre-pandemic intranasal vaccine.

Abstract

Background

The emergence of new influenza strains with unpredictable antigenic properties poses a significant vaccination challenge. The increasing incidence of human H5 infections underscores the urgent need for effective pre-pandemic vaccines.

Methods

The UniFluVec and UniFluVec-wtNS1 viruses were designed as H1N1pdm vaccine candidates. Both viruses contained a heterologous A/Singapore/1/57-like (H2N2) NEP gene, which served as an attenuation factor. UniFluVec additionally carried a truncated to 124 amino acids NS1 gene, and an insertion of conserved influenza sequences. UniFluVec-wtNS1 retained the wild-type NS1 gene. The impact of NS1 and NEP modifications on attenuation and phenotypic markers was assessed in cells and mice. Safety and prophylactic efficacy were assessed in ferrets following a single intranasal immunisation with the maximum feasible dose (8.7 log10 EID50), followed by challenge with the highly pathogenic avian influenza virus (HPAIV) A/Indonesia/5/2005 (H5N1).

Results

Modifications in NS1 and NEP independently and synergistically induced a temperature-sensitive phenotype and enhanced type I/II interferon response, resulting in a highly attenuated vaccine profile. UniFluVec, incorporating both modifications within the NS genomic segment, demonstrated superior viral clearance, reducing lung damage, and ensuring 100 % survival in infected animals.

Conclusion

The replication-deficient UniFluVec vector demonstrates safety, immunogenicity, and protective efficacy against the heterologous HPAIV strain in ferrets following a single intranasal administration.

Source: Vaccine, https://www.sciencedirect.com/science/article/pii/S0264410X25010928?via%3Dihub

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Highly pathogenic avian #influenza in South #America, 2022-25: temporality, affected #species, and southwards #expansion to #Antarctic region.

 

Abstract

The H5N1 highly pathogenic avian influenza (HPAI) virus has caused severe global losses, reaching South America in 2022 and Antarctica in 2024. Here we synthesize outbreak reports submitted to the World Organization for Animal Health (WOAH) by South American countries and document the virus's unprecedented expansion into Antarctica, affecting wild birds, wild mammals, and domestic poultry. More than 6 million domestic birds died or were culled, mostly from commercial operations. Of the 11 South American countries that reported H5N1 to WOAH, 10 reported infections in wild birds, spanning 104 species, 59.62% of which are migratory and predominantly non-trans-equatorial. Marine mammal cases occurred after wild bird detections, with the South American sea lion (Otaria flavescens) most affected, and several Antarctic bird species with migratory behavior were also reported in South America. To complement outbreak data, we examined available genomic sequences through phylogenetic and time-calibrated Bayesian analyses, which revealed multiple introduction events, viral diversity across regions, and evidence of interspecies transmission dynamics. These findings highlight the extensive ecological reach of H5N1 in the Southern Hemisphere and underscore the urgent need for a One Health approach that strengthens wildlife and backyard-poultry surveillance while fostering coordinated regional action to control and prevent further spread of HPAI.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.10.03.680239v1

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Paradise, Tintoretto (c. 1592)

 

Public Domain.

Source: WikiArt, https://www.wikiart.org/en/tintoretto/paradise

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First serological #evidence of equine #coronavirus and #SARS-CoV-2 in #horses in North #Africa

 

Abstract

Viral diseases cause significant economic losses within the equine population. Horses are susceptible to equine coronavirus (ECoV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), although only ECoV has been associated to clinical disease. The aim of this study was to investigate, for the first time in Algeria, the seroprevalence of ECoV and SARS-CoV-2 antibodies and the prevalence of ECoV infection in horses. In 2022, a total of 299 serum samples was collected from horses aged 1 to 27 years. Serological analysis for the presence of ECoV and SARS-CoV-2 was performed using a validated in-house and a commercially available ELISA, respectively. In addition, fecal samples of these animals were tested for the presence of ECoV RNA by RT-qPCR. SARS-CoV-2-ELISA positive sera with high S/P ratios and negative samples close to the doubtful threshold were retested using a virus neutralization test (VNT). The seroprevalence of ECoV and SARS-CoV-2 in the tested horses was 63.5% (190/299) and 4.3% (13/299), respectively. Among CoVs-seropositive horses, six were seropositive for both ECoV and SARS-CoV-2, thus 6/10 sera were VNT positive, including two ELISA-negative samples for SARS-CoV-2. ECoV seroprevalence varied according to age, breed and sex. None of the fecal samples tested positive for ECoV. Antibodies against SARS-CoV-2 were confirmed by VNT in six samples (2%). One SARS-CoV-2-positive serum tested by ELISA and confirmed through VNT was cytotoxic for VERO cells. This study is the first to report the circulation of ECoV and SARS-CoV-2 in the Algerian horse population. Further studies are necessary to isolate and obtain molecular characterisation of ECoV and SARS-CoV-2 from horses in Algeria.

Source: Veterinary Research Communications, https://link.springer.com/article/10.1007/s11259-025-10928-0

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History of Mass Transportation: The Snowdon Mountain Railway Steam Locomotive (1922)

 

Von A.M.Hurrell - Photographer - A.M.Hurrell, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=423388

Source: Wikipedia, https://de.wikipedia.org/wiki/Schweizerische_Lokomotiv-_und_Maschinenfabrik

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#Influenza and Other Respiratory Viruses Research #References (by AMEDEO, October 4 '25)

 

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4. GAILLET A, Layese R, Fourati S, Celante H, et al
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5. LI K, Bont LJ, Weinberger DM, Pitzer VE, et al
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6. LI K, Pitzer VE, Weinberger DM
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#Chikungunya virus disease - #Global #situation (#WHO D.O.N., Summary, Oct. 3 '25)

 

Situation at a glance

In 2025, a resurgence of chikungunya virus (CHIKV) disease was noted in a number of countries, including some that had not reported substantial case numbers in recent years. 

Between 1 January and 30 September 2025, a total of 445 271 suspected and confirmed CHIKV disease cases and 155 deaths were reported globally from 40 countries, including autochthonous and travel imported cases. 

Some WHO Regions are experiencing significant increases in case numbers compared to 2024, although others are currently reporting lower case numbers. 

This uneven distribution of cases across regions makes it challenging to characterize the situation as a global rise, however, given the ongoing outbreaks reported globally in 2025, the potential for further spread remains significant. 

CHIKV disease can be introduced into new areas by infected travelers and local transmission may be established if there is the presence of Aedes mosquito and a susceptible population. 

The risk is heightened by limited population immunity in previously unaffected areas, favorable environmental conditions for vector breeding, gaps in surveillance and diagnostic capacity, and increased human mobility and trade. 

Strengthening disease surveillance, enhancing vector surveillance and control, and improving public health preparedness are essential to mitigate the risk of further transmission. 

Prior to 2025, current or previous autochthonous transmission of CHIKV has been reported from 119 countries and territories. 

A total of 27 countries and territories across six WHO regions have established competent populations of Aedes aegypti mosquitoes but have not yet reported autochthonous CHIKV transmission. 

Additional countries have established populations of Aedes albopictus mosquitoes, which can also transmit CHIKV, and in which transmission efficiency is enhanced for CHIKV lineages with the E1 226V mutation. 

The presence of these vectors poses a continuous threat of chikungunya introduction and spread in previously unaffected areas. 

Increased CHIKV transmission is driven by multiple factors that include: 

- the expanded geographic distribution of Aedes mosquitoes related to transportation in conveyances and 

- climate change, 

- unplanned urbanization, 

- poor water management, and 

- weakened vector surveillance and control. 

CHIKV disease typically causes high population attack rates. In smaller settings such as islands, the transmission dynamics can be temporarily interrupted once a proportion of the population becomes infected and subsequently immune. 

In larger populations however, where enough individuals remain immunologically susceptible, transmission can persist over time, leading to sustained outbreaks. 

These outbreaks often place a significant burden on healthcare systems due to the number of affected individuals. 

Countries differ in their ability to detect and report chikungunya and other vector-borne diseases, with many outbreaks identified only retrospectively, hindering effective public health responses. 

Early detection of cases, particularly in persons at risk for severe CHIKV disease, and timely access to appropriate medical care are essential for minimizing clinical complications and reducing mortality. 

The variation in distribution of cases across regions highlights the importance of continued investment in surveillance, preparedness, and response capacities to address evolving regional dynamics. 

WHO continues to call on all countries to strengthen their healthcare and laboratory systems to enable rapid detection, timely reporting, and effective response to chikungunya outbreaks.

(...)

Source: World Health Organization, https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON581

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#Italy, Integrated #WNV & #USUV #Surveillance - Weekly Bulletin No. 12, 2 October 2025: 38 new confirmed cases (Summary)

 

{Summary}

-- During current epidemiological week (from 25 September to 1rst October 2025), 38 new confirmed human infection with West Nile Virus have been reported. 

-- Since the beginning of the epidemic season, 718 confirmed cases have been recorded in Italy (they were 680 in the last bulletin), of these: 

- 341 were West Nile Neuroinvasive Disease (WNND): 15 in Piedmont, 51 Lombardy, 30 Veneto, 4 Friuli-Venezia Giulia, 1 Liguria, 27 Emilia-Romagna, 11 Tuscany, 1 Marche, 84 Latium, 2 Molise, 79 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 2 Sicily, 25 Sardinia, 

- 57 were asymptomatic cases in blood donors, 

- 309 were West Nile Fever cases (1 imported from Kenya, 1 Egypt, and one Maldives), 

- 4 asymptomatic cases, 

- 7 unspecified cases. 

-- Among confirmed cases, there have been 49 fatalities: 7 in Piedmont, 5 Lombardy, 2 Emilia-Romagna, 18 Latium, 14 Campania, 2 Calabria, 1 Sardinia. 

- The Case-Fatality Rate in WNND cases was 14.4% (it was 20% in 2018 and 14% in 2024. 

-- This season 10 confirmed Usutu virus human infections have been recorded: 2 in Piedmont, 3 Lombardy, 2 Veneto, 3 Latium.

(...)

Source: High Institute of Health, https://www.epicentro.iss.it/westnile/bollettino/Bollettino_WND_2025_12.pdf

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Fatal #Human #H3N8 #Influenza Virus has a Moderate #Pandemic #Risk

 

Abstract

In China, low pathogenic avian influenza (LPAI) H3N8 virus is widespread among chickens and has recently caused three zoonotic infections, with the last one in 2023 being fatal. Here we evaluated the relative pandemic risk of this 2023 zoonotic H3N8 influenza virus, utilizing our previously published decision tree. Serological analysis indicated that a large proportion of the human population does not have any cross-neutralizing antibodies against this H3N8 strain. LPAI H3N8 displayed a dual affinity for a2-3 and a2-6 sialic acids and replicated efficiently in human bronchial epithelial cells. Furthermore, we observed H3N8 transmission via direct contact but not aerosols to ferrets with pre-existing H3N2 immunity. Although pre-existing H3N2 immunity resulted in a shortened disease course in ferrets, it did not reduce disease severity or replication in the respiratory tract. This study suggests that this zoonotic H3N8 strain has moderate pandemic potential and emphasizes the continued need for avian influenza surveillance.

Competing Interest Statement

The authors have declared no competing interest.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.10.02.679960v1

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Impact of naturally occurring #hemagglutinin substitutions on antigenicity and fitness of #influenza #H5N1 virus

 

Abstract

In 2024, a human infection with clade 2.3.4.4b highly pathogenic avian influenza A(H5N1) virus was identified in the United States in an individual with no known exposure. Genetic analysis revealed two hemagglutinin (HA) substitutions, P136S and A156T, which may alter viral antigenicity. Virus isolation was unsuccessful, preventing timely serologic analysis. To overcome this limitation, we generated recombinant viruses by reverse genetics and characterized the effects of the substitutions on antigenicity, receptor binding, and replicative fitness. The A156T substitution introduced a potential N-linked glycosylation site, resulting in altered antigenicity and reduced replication in primary human nasal epithelial cells and ferrets. Importantly, the A(H5N1) candidate vaccine virus (CVV) IDCDC-RG80A, which possesses HA-T156, remained antigenically effective against viruses with and without these substitutions. These findings highlight the importance of sequencing, reverse-genetics approaches, and antigenically similar CVVs such as IDCDC-RG80A, for pandemic preparedness against evolving clade 2.3.4.4b A(H5N1) viruses.

Source: npj Viruses, https://www.nature.com/articles/s44298-025-00154-5

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Opportunity Drives #Spillover: Serological #Surveillance across #Carnivores, #Omnivores and #Herbivores in an #HPAIV #H5 Hotspot in North-East #Germany, 2023-2025

 

Abstract

In North-East Germany's offshore islands and mainland coast, wild ruminants, boar, and carnivores were tested for H5-HPAI antibodies. Wild ruminants were seronegative; 3.5% of boar and 12.5-21.9% of carnivores were seropositive, evidencing frequent spillover. Because such events may accelerate mammalian - and ultimately human - adaptation, sustained One-Health monitoring is essential.

Competing Interest Statement

The authors have declared no competing interest.

Funder Information Declared

European Union, 101084171 "KAPPA-FLU"

Helmholtz Institute for One Health, WiMoPOH

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.09.30.678011v1

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

 

A laying hens farm in Nordrhein-Westfalen Region.

Source: WOAH, https://wahis.woah.org/#/in-review/6832

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#Ebola Virus Disease in the #DRC - External #Situation #Report 03 - September 28 '25 (#WHO, summary)

 

Date of issue: 30 September 2025

Data as reported by: 28 September 2025

{Summary}

The Ebola virus disease outbreak in the Democratic Republic of the Congo continues, with signs of a notable decline in transmission. 

Since our last update (Situation Report #2), a total of seven new cases have been reported, comprising six confirmed and one probable cases (retrospectively validated). 

The new cases were detected across three health areas within Bulape Health Zone, namely, Bulape (n=4), Mpianga (n=2), and Dikolo (n=1). 

During the same reporting period, seven deaths occurred among newly identified and previously hospitalized cases. The reported deaths were distributed across Dikolo (n=3), Bulape (n=2), Mpianga (n=1), and Bulape Communitaire (n=1) health areas.

As of 28 September 2025, a total of 64 cases (53 confirmed and 11 probable), including 42 deaths (31 confirmed, 11 probable), have been reported from Bulape Health Zone, Kasai Province, Democratic Republic of the Congo. 

The overall case fatality ratio (CFR) is 65.6%. 

Cumulatively, five confirmed cases have been reported among healthcare workers, including three deaths. 

The outbreak remains confined to six affected health areas out of the 21 that make up Bulape Health Zone.

Cases to date range in age from 0 (newborn) to 65 years. 

Since the onset of the outbreak, the majority of cases have been reported among females (57.8%, n=37), children aged 0–9 years (25.0%, n=16), and individuals aged 20–29 years (23.4%, n=15). 

Mortality has also been concentrated among these groups, with females accounting for over half of the reported deaths (57.1%, n=24) and children under 10 years representing 31.0% of deaths (n=13). 

The CFR is slightly higher among males (66.7%) compared to females (64.9%). 

In the past two weeks, fewer cases (n = 2) have been reported among children (0-9 years old). 

A decreasing CFR trend has been observed over time with improvement in surveillance (early case detection and isolation) and the quality of case management (prompt and high-quality treatment).

As of 28 September 2025, a total of 1 787 contacts were under follow-up, with 1 735 (97.1%) seen in the last 24 hours. 

Nine (9) cases were successfully treated and discharged following recovery while 13 are currently in treatment as of 28 September 2025.

(...)

Source: ReliefWeb, https://reliefweb.int/attachments/de19e29d-1f89-4ad2-a086-e9afcdce91cc/DRC_EVD_External_Sitrep_28Sept2025.pdf

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#LongCOVID associated with #SARS-CoV-2 #reinfection among #children and adolescents in the #omicron era (RECOVER-EHR): a retrospective cohort study

 

Summary

Background

Post-acute sequelae of SARS-CoV-2 infection (PASC) remain a major public health challenge. Although previous studies have focused on characterising PASC in children and adolescents after an initial infection, the risks of PASC after reinfection with the omicron variant remain unclear. We aimed to assess the risk of PASC diagnosis (U09.9) and symptoms and conditions potentially related to PASC in children and adolescents after a SARS-CoV-2 reinfection during the omicron period.

Methods

This retrospective cohort study used data from 40 children's hospitals and health institutions in the USA participating in the Researching COVID to Enhance Recovery (RECOVER) Initiative. We included patients younger than 21 years at the time of cohort entry; with documented SARS-CoV-2 infection after Jan 1, 2022; and who had at least one health-care visit within 24 months to 7 days before the first infection. The second SARS-CoV-2 infection was confirmed by positive PCR, antigen tests, or a diagnosis of COVID-19 that occurred at least 60 days after the first infection. The primary endpoint was a clinician-documented diagnosis of PASC (U09.9). Secondary endpoints were 24 symptoms and conditions previously identified as being potentially related to PASC. We used the modified Poisson regression model to estimate the relative risk (RR) between the second and first infection episodes, adjusted for demographic, clinical, and health-care utilisation factors using exact and propensity-score matching.

Findings

We identified 407 300 (87·5%) of 465 717 eligible children and adolescents with a first infection episode and 58 417 (12·5%) with a second infection episode from Jan 1, 2022, to Oct 13, 2023, in the RECOVER database. 233 842 (50·2%) patients were male and 231 875 (49·8%) were female. The mean age was 8·17 years (SD 6·58). The incident rate of PASC diagnosis (U09.9) per million people per 6 months was 903·7 (95% CI 780·9–1026·5) in the first infection group and 1883·7 (1565·1–2202·3) in the second infection group. Reinfection was associated with a significantly increased risk of an overall PASC diagnosis (U09.9) (RR 2·08 [1·68–2·59]) and a range of symptoms and conditions potentially related to PASC (RR range 1·15–3·60), including myocarditis, changes in taste and smell, thrombophlebitis and thromboembolism, heart disease, acute kidney injury, fluid and electrolyte disturbance, generalised pain, arrhythmias, abnormal liver enzymes, chest pain, fatigue and malaise, headache, musculoskeletal pain, abdominal pain, mental ill health, POTS or dysautonomia, cognitive impairment, skin conditions, fever and chills, respiratory signs and symptoms, and cardiovascular signs and symptoms.

Interpretation

Children and adolescents face a significantly higher risk of various PASC outcomes after reinfection with SARS-CoV-2. These findings add to previous evidence linking paediatric long COVID to multisystem effects and highlight the need to promote vaccination in younger populations and support ongoing research to better understand PASC, identify high-risk subgroups, and improve prevention and care strategies.

Funding

National Institutes of Health.

Source: The Lancet Infectious Diseases, https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00476-1/fulltext?rss=yes

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

 

{By © Hans Hillewaert, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5548312}

Wild species: Black-headed Gull (8), Mew Gull (8).

{Norðurland vestra Region} Approximately 20 gulls were found dead at the beach. A pooled sample from 3 mew gulls was taken and found positive for HPAI H5N5.

{Icelandic Exclusive Economic Zone} Approximately 20 gulls were found dead at the beach. A pooled sample from 3 black-headed gulls was taken and found positive for HPAI H5N5.

Source: WOAH, https://wahis.woah.org/#/in-review/6816

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

 

{England, Cumberland} A chicken breeders flock of 43,339 birds. Increased mortality and other clinical signs (lethargy, respiratory distress, swollen heads, tremors, watery diarrhoea and excessive oral discharge) were reported. Samples taken and were tested positive for HPAI H5N1.

Source: WOAH, https://wahis.woah.org/#/in-review/6824

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

 

{By Andreas Trepte - Own work, CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=37690004}

A wild Whooper Swan in Vidzemes Region.

Source: https://wahis.woah.org/#/in-review/6825

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