ETIDIOH - NEW

Abstract Since March 2024, highly pathogenic avian influenza A(H5N1) viruses have caused outbreaks in dairy cattle and poultry in the United States, and they continue to spill over into humans . However, data on human immune response to those viruses is limited. We report neutralizing antibody responses in 2 dairy farm worker H5N1 cases. Source: US Centers for Disease Control and Prevention,  https://wwwnc.cdc.gov/eid/article/31/4/25-0007_article ____

{Excerpt} Time Period: February 23 - March 01, 2025 - H5 Detection :  8 sites ( 1.8% ) - No Detection :  445 sites ( 98.2% ) - No samples in last week :  100 sites (...) Source: US Centers for Disease Control and Prevention,  https://www.cdc.gov/bird-flu/h5-monitoring/index.html ____

The UK Health Security Agency has been informed under the International Health Regulations that an individual travelled to England from Nigeria while they were unwell with Lassa fever at the end of February. The individual returned to Nigeria where they were diagnosed . We are now working to identify people who were in contact with the affected individual while they were in the country. Lassa fever does not spread easily between people and the overall risk to the public is very low . If you have not been contacted by UKHSA then you are very unlikely to have had any exposure to Lassa fever and do not need to take action. Lassa fever causes acute infections which can range from very mild symptoms through to a severe viral haemorrhagic fever. People usually become infected with Lassa virus through exposure to food or household items contaminated with urine or faeces of infected rats – present in some West African countries where the disease is endemic. The virus can also be spread between...

 A wild Carrion Crow in Khabarovsk Region. Source:  https://wahis.woah.org/#/in-review/6304 ____

{England} Commercial turkey fattening unit with 27,658 turkeys. Increased mortality and other clinical signs of HPAI reported. The samples were positive for HPAI H5N1. Source: WOAH,  https://wahis.woah.org/#/in-review/6314 ____

 This event will collect the detections made by sampling carried out in 2025. Peregrine falcon , adult male, transmitted to a Centre for the protection of endangered species on 05/02/2025 with nervous symptoms, that died on 06/02/2025. The necropsy was performed at the Wildlife Center for Analysis and Diagnosis. Source: WOAH,  https://wahis.woah.org/#/in-review/6316 ____

Significance Middle East respiratory syndrome coronavirus (MERS-CoV) is a highly pathogenic coronavirus that continues to cause periodic outbreaks in humans with a case-fatality rate of approximately 35%. MERS-CoV generally transmits poorly, but superspreading events are well documented. Efficient human-to-human transmission of respiratory viruses generally correlates with a tropism for the upper respiratory tract, but this tropism for MERS-CoV remains poorly understood. Characterizing the MERS-CoV tropism in the human upper respiratory tract is of critical importance to understand its epidemiology and pandemic potential of future MERS-CoV variants and other dipeptidyl peptidase 4 (DPP4)-utilizing coronaviruses present in animal reservoirs. Abstract Transmissibility of respiratory viruses is a complex viral trait that is intricately linked to tropism. Several highly transmissible viruses, including severe acute respiratory syndrome coronavirus 2 and Influenza viruses, specifically targ...

Abstract Background In late 2023, the first human case caused by an H10N5 avian influenza virus (AIV) was diagnosed in China . H10Ny AIVs have been identified in various poultry and wild birds in Eurasia, the Americas, and Oceania. Methods We analyzed the clinical data of the H10N5 AIV-infected patient, isolated the virus, and evaluated the virus receptor-binding properties together with the H10N8 and H10N3 AIVs identified in humans and poultry. The genomic data of the human-infecting H10N5 strain and avian H10Ny AIVs (n = 48, including 16 strains of H10N3 and 2 strains of H10N8) from live poultry markets in China , during 2019–2021, were sequenced. We inferred the genetic origin and spread pattern of the H10N5 AIV using the phylodynamic methods. In addition, given all available nucleotide sequences, the spatial-temporal dynamics, host distribution, and the maximum-likelihood phylogenies of global H10 AIVs were reconstructed. Findings The first H10N5 AIV-infected human case co-infected...

Two wild cats, two European Polecats, Forty-four Domestic Mustelidae, Twenty-two foxes in various Regions. Source: WOAH,  https://wahis.woah.org/#/in-review/4971?reportId=172740&fromPage=event-dashboard-url ____

As of February 28, 2025 CDC assessed the risk from H5N1 viruses to the U.S. general population and to populations in the United States with contact with potentially infected animals, including through contaminated surfaces or fluids . Risk describes the potential public health implications and significance of an outbreak for populations assessed. See definitions below for more detail. {Risk posed by H5N1 viruses to the United States. Please see methods section for further information on definitions of terms.} ___ The purpose of this assessment is to evaluate the current public health risk of H5N1 viruses to the general U.S. population and to those in contact with potentially infected animals or contaminated surfaces or fluids, and to inform public health preparedness efforts. CDC assessed risk by considering both likelihood and impact of infection in each population (...). Both the likelihood and impact of infection are assessed at a population level. Likelihood of infection refers to ...

Abstract The recent spillover events of highly pathogenic avian influenza (HPAI) A(H5N1) clade 2.3.4.4b to dairy cattle , and high viral shedding in the milk from infected animals, has created concern that milk and dairy products could be a route for human infection . It has been demonstrated that pasteurization is effective in inactivating A(H5N1) in milk. However, multiple dairy products are made with unpasteurized but thermised milk . The aim of this study was to examine whether some conditions commonly used for thermisation are effective against inactivation of A(H5N1) in whole milk. For this purpose, we artificially inoculated whole raw cow milk with 6.5 log10 EID50 A(H5N1) and heated for 15 seconds at 60°C, 63°C and 66°C , the viral infectivity was tested using embryonated chicken eggs. We observed over 4 and 5 log10 reduction in viral infectivity at 60°C and 63°C, respectively. The viral infectivity was reduced to below the detection limit at 66°C. We also calculated the D-value...

Abstract Highly pathogenic H5N1 avian influenza viruses (HPAIV) belonging to lineage 2.3.4.4b emerged in Chile in December 2022, leading to mass mortality events in wild birds, poultry, and marine mammals and one human case . We detected HPAIV in 7,33% (714/9745) of cases between December 2022–April 2023 and sequenced 177 H5N1 virus genomes from poultry, marine mammals, a human, and wild birds spanning >3800 km of Chilean coastline . Chilean viruses were closely related to Peru’s H5N1 outbreak, consistent with north-to-south spread down the Pacific coastline . One human virus and nine marine mammal viruses in Chile had the rare PB2 D701N mammalian-adaptation mutation and clustered phylogenetically despite being sampled 5 weeks and hundreds of kilometers apart . These viruses shared additional genetic signatures , including another mammalian PB2 adaptation (Q591K, n = 6), synonymous mutations, and minor variants. Several mutations were detected months later in sealions in the Atlanti...

ABSTRACT The evolution of the antibody response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is impacted by the nature and number of antigenic exposures . First-generation coronavirus disease 2019 (COVID-19) vaccines encoded an ancestral spike protein . Updated bivalent vaccines and breakthrough infections have shaped the intricate diversity of the polyclonal antibody response and specificity of individual antibody clones. We and others previously showed that bivalent vaccines containing the ancestral and Omicron (BA.5) spikes induce high levels of cross-reactive antibodies but undetectable BA.5-specific antibodies in serum. Here, we assessed sera collected before as well as 1 and 3 months following administration of an updated XBB.1.5 monovalent vaccine to individuals with diverse infection and vaccination histories. Vaccination increased neutralization against recent variants of concern , including HV.1, JN.1 , and the vaccine-homologous XBB.1.5. Antibody bindi...

ABSTRACT The highly pathogenic avian influenza virus (HPAIV) A(H5N1) has caused the most extensive and severe epizootic event affecting both poultry and wild birds globally. This study investigated the impact of HPAIV on the breeding population of the Black-headed Gull Chroicocephalus ridibundus , the most abundant gull species in Poland . During the 2023 outbreak, this species was reported as the most frequently infected in the country. A higher-than-natural adult mortality rate (greater than 1.5% of the breeding individuals) was observed in 114 surveyed colonies across all regions of Poland. Laboratory tests confirmed the presence of HPAIV in all 17 colonies sampled, with average adult mortality estimated at 26.1%, and ranging from 1.7% to 77.8%. The estimated mortality rate across all surveyed colonies was 22.2%. Extrapolations across the entire Polish breeding population (at least 115,000 pairs according to the national census) indicated that approximately 51,000 adult Black-headed...

Abstract Objectives This study aims to provide real-time surveillance of epidemiological outbreaks of avian influenza in humans and mammals . The primary objective is to understand and track the dynamics of outbreaks as they develop, facilitating timely interventions and informed public health decisions. The data collection is part of a broader initiative focused on improving preparedness and response capabilities to emerging health threats . Data description The dataset includes comprehensive and up-to-date information on epidemiological patterns, including geographic spread, incidence rates, and demographic factors. Collected through systematic monitoring and reporting systems, this dataset is invaluable to researchers seeking to understand the evolving nature of avian influenza outbreaks in the global context. By sharing these data, we aim to contribute to the collective knowledge base by supporting evidence-based strategies for effective public health management and intervention. S...

Abstract Ferrets are widely used to model airborne transmission of influenza viruses in humans. Airborne transmission is evaluated by infecting donor ferrets with a high virus dose (106 infectious units) and monitoring transmission to contact animals sharing the same airspace . However, humans can be infected with a broad range of influenza virus doses. Therefore, we evaluated the relationship between virus inoculation dose and transmission for two pandemic influenza viruses in ferrets. Donor ferrets were inoculated with 100 to 106 tissue culture infectious dose 50 (TCID50) of the 2009 pandemic H1N1 or 1968 H3N2 pandemic virus , and were then paired with respiratory contacts . Using the proportion of donors that became infected across virus doses, we calculated the infectious dose 50 (ID50). Subsequently, by comparing the proportion of respiratory contacts that became infected, we calculated the transmissible dose 50% (TD50): the donor inoculation dose that resulted in transmission to ...

Abstract Since the first emergence of highly pathogenic avian influenza (HPAI) H5N1 viruses in dairy cattle , the virus has continued to spread, reaching at least 16 states and at least 950 dairy herds in the United States . Subsequently, spillovers of the virus from dairy cattle to humans have been reported. Pigs are an important reservoir in influenza ecology because they serve as a mixing vessel in which novel reassortant viruses with pandemic potential can be generated. Here, we show that oro-respiratory infection of pigs resulted in productive replication of a bovine-derived HPAI H5N1 B3.13 virus. Infectious viruses were mainly identified in the lower respiratory tract of principal infected pigs, and sero-conversion was observed in most of the principal pigs at later time points. In one animal, we detected the emergence of a mutation in hemagglutinin (HA) previously associated with increased affinity for mammalian-type alpha 2,6-linked sialic acid receptors , but this mutation did...

Abstract Acute Hemorrhagic Conjunctivitis (AHC) is primarily caused by viral infections, with Coxsackievirus A-24v (CV-A24v) being a significant culprit. Enteroviruses , including CV-A24v, are responsible for global AHC outbreaks . Over time, CV-A24v has evolved, and genotype IV (GIV) has become the dominant strain. This study focused on examining the genetic features and evolutionary trends of CV-A24v responsible for the recent AHC outbreak of 2023 in India . Researchers isolated viral strains from ocular swabs and confirmed the presence of CV-A24v using reverse transcriptase quantitative PCR (RT-qPCR) and whole-genome sequencing . Genomic comparisons between isolates of 2023 and those from a previous outbreak in 2009 were conducted. Phylogenetic analysis revealed that the 2023 isolates formed a distinct cluster within GIV-5 and were related to recent strains from China and Pakistan . The older Indian isolates from 2009 grouped with GIV-3. New subclades, GIV-6 and GIV-7, were also ide...

 A poultry farm in Durrës Region. Source: WOAH,  https://wahis.woah.org/#/in-review/6305 ____

ABSTRACT The COVID-19 pandemic has greatly enhanced our understanding of CD8+ T cell immunity and their role in natural infection and vaccine-induced protection. Rapid and early SARS-CoV-2- specific CD8+ T cell responses have been associated with efficient viral clearance and mild disease . Virus-specific CD8+ T cell responses can compensate for waning, morbidity-related , and iatrogenic reduction of humoral immunity. After infection or vaccination, SARS-CoV-2-specific memory CD8+ T cells are formed, which mount an efficient recall response in the event of breakthrough infection and help to protect from severe disease. Due to their breadth and ability to target mainly highly conserved epitopes, SARS-CoV-2-specific CD8+ T cells are also able to cross-recognize epitopes of viral variants , thus maintaining immunity even after the emergence of viral evolution. In some cases, however, CD8+ T cells may contribute to the pathogenesis of severe COVID-19. In particular, delayed and uncontrolle...