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#Evidence of #Viremia in Dairy #Cows Naturally Infected with #Influenza A {#H5N1} Virus, #California, #USA

Abstract We confirmed influenza A virus (IAV) by PCR in serum from 18 cows on 3 affected dairy farms in California, USA . Our findings indicate the presence of viremia and might help explain IAV transmission dynamics and shedding patterns in cows. An understanding of those dynamics could enable development of IAV mitigation strategies. Source: US Centers for Disease Control and Prevention,  https://wwwnc.cdc.gov/eid/article/31/7/25-0134_article ____

#USA, Monitoring for Avian #Influenza A(#H5) Virus In #Wastewater (US CDC, May 29 '25) {Updated}

  {Excerpt} Time Period: May 18, 2025 - May 24, 2025 -- H5 Detection :  17 sites ( 5.0% ) - No Detection :  322 sites ( 95.0% ) - No samples in last week :  116 sites (...) Source: US Centers for Disease Control and Prevention,  https://www.cdc.gov/bird-flu/h5-monitoring/index.html ____

#Surveillance and #Coinfection Dynamics of Infectious Bronchitis Virus and Avian #Influenza #H9N2 in Moroccan Broiler Farms (2021–2023): Phylogenetic Insights and Impact on Poultry Health

Abstract Infectious bronchitis virus (IBV) and low-pathogenic avian influenza virus (LPAIV) H9N2 are commonly identified in poultry , individually or in association with other pathogens. This study monitored 183 broiler farms affected by respiratory diseases across seven regions of Morocco from January 2021 to December 2023. Among these farms, 87.98% were vaccinated against IBV, while 57.92% were against AI H9N2 . Abnormally high mortality rates were observed in 44.26% of the farms, with 24.69% of cases attributed to IBV, 50.62% to LPAI H9N2, and 13.58% due to coinfection with both IBV and H9N2 . RT-PCR analysis of tissue samples and cloacal and tracheal swabs collected from 183 broiler farms revealed that 33.33% were positive for IBV and 34.97% for H9N2. Coinfection by IBV and H9N2 was detected in 12.57% of cases , peaking at 17% in 2022. Co-infected flocks exhibited severe clinical signs and lesions, such as reduced food consumption, diarrhea, and renal issues. The predominant lesion...

#Anthrax - #Thailand (#WHO, D.O.N., May 29 '25)

  {Summary} Situation at a glance In early May 2025, the International Health Regulations National Focal Point (IHR NFP) for Thailand notified WHO of four cases of cutaneous anthrax .  One of the affected individuals died as a result of disease complications, while the remaining three cases were hospitalized and received appropriate medical care .  All reported cases had direct contact with cattle suspected to be infected with anthrax.  A rapid field investigation and response was conducted by the national health authorities.  All potentially exposed individuals were identified, and all high-risk contacts received post-exposure prophylaxis .  On 28 May, an additional case was announced who was associated with the slaughtering of cattle .  Disease control measures , including animal quarantine, and vaccination campaign targeting cattle withing five km radius, public awareness campaigns, and enhanced surveillance, were implemented in the affected area....

#Update on the #Epidemiology of Middle East Respiratory Syndrome {#MERS} #Coronavirus — #Worldwide, 2017–2023 (US CDC, MMWR)

  Summary -- What is already known about this topic? - Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) is a zoonotic virus transmitted sporadically from camels to humans , with limited subsequent human-to-human transmission . Most reported human cases of MERS have occurred in or near the Arabian Peninsula . Standardized clinical and epidemiologic criteria are used to determine who in the United States should be tested for MERS-CoV. In the United States , the last identified and confirmed MERS cases occurred in 2014 . -- What is added by this report? - Global reported MERS cases have declined substantially since the COVID-19 pandemic. Numbers of travelers entering the United States from in or near the Arabian Peninsula declined during the COVID-19 pandemic, but now have returned to prepandemic levels. U.S. MERS-CoV testing declined during 2017–2023 and remains low relative to prepandemic years. Clinical and epidemiologic criteria to guide U.S. testing were updated in ...

Altered germinal center responses in mice vaccinated with highly pathogenic avian #influenza A(#H5N1) virus

Highlights •  Different immune responses in mice vaccinated with influenza A(H5N1) than with other subtypes. •  Highly pathogenic avian influenza A(H5N1)-vaccinated mice had altered germinal center responses. •  A(H5N1)-vaccinated mice had fewer dLN germinal centers and more extrafollicular B cells. •  A(H5N1)-vaccinated mice had more dLN follicular helper and regulatory T cells. •  Our study represents a timely assessment of A(H5N1) risk to human health. Abstract Highly pathogenic avian influenza (HPAI) H5N1 virus vaccines typically yield lower neutralizing antibody titers in animals than influenza A virus (IAV) vaccines derived from other viral subtypes. To understand these differences, we compared the cellular immune responses in the draining lymph nodes (dLNs) of mice vaccinated with an inactivated whole H5N1 vaccine to those in mice vaccinated with seasonal H1N1pdm09, H7N9, or H9N2 IAV vaccines . H5N1-vaccinated mice exhibited reduced serum neutralizing ant...

Stability of #influenza viruses in the #milk of #cows and #sheep

Abstract In late 2023, H5N1 high pathogenicity avian influenza (HPAIV) started circulating in dairy cattle in the USA . High viral titres were detected in milk from infected cows , raising concerns about onwards human infections . Although pasteurisation was shown to effectively inactivate influenza viruses in milk, unpasteurised milk still poses a risk of infection, both from occupational exposure in dairies and from the consumption of raw milk. We therefore assessed how long influenza viruses could remain infectious for in milk without heat inactivation. We examined the stability of a panel of influenza viruses in milk , including a contemporary H5N1 HPAIV and a variety of other influenza A and D viruses. We incubated viruses in cows' milk under laboratory conditions : at room temperature to simulate exposure in dairies and at 4°C to simulate exposure to refrigerated raw milk. Following an isolated report of H5N1 viral RNA being detected in milk from a sheep in the UK , we also c...

G57 #genotype of BJ/94-like #H9N2 lineage exhibits increased #replication & virulence in chickens compared to G1 Middle East Group B lineage

Abstract Avian influenza H9N2 viruses cause significant economic losses to the poultry industry and pose a public health risk due to their potential to reassort with other avian influenza viruses, generating strains with zoonotic and pandemic potential . Two major H9N2 lineages dominate globally: the G1 lineage (genotype G1-B), prevalent in the Middle East, Africa and the Indian subcontinent , and the BJ/94 lineage (predominantly genotype G57), dominant in China, Vietnam, South Korea, Indonesia, and the Far East . We investigated replication, transmission, and pathogenicity of representatives of these two lineages, linking genotype to phenotype. The G57 strain A/Ck/Vietnam/H7F-14-BN4-315/2014 (Vietnam/315) was more lethal to chicken embryos than the G1-B strain A/chicken/Pakistan/UDL-01/2008 (Pakistan/UDL-01). Vietnam/315 exhibited higher replication in both directly infected and contact chickens, with increased virus shedding from the oropharynx and cloaca. In contrast, Pakistan/UDL-0...

Post-mortem #investigation of role of endemic #human #coronaviruses in causal pathway to death amongst #children under 5 in LMIC: findings from the Child Health & Mortality Prevention Surveillance

Highlights •  Large study on the contribution of HCoV to childhood deaths •  Supports vigilance or further investigations into HCoV pathogenesis •  Potential information for the role Covid-19 will play during severe childhood disease •  Highlights the importance of polymicrobial infection during severe disease episodes Abstract Background Endemic human coronaviruses (HCoV-229E, HKU1, NL63, and OC43) are common causes of mild or asymptomatic respiratory infections in children but are considered rare causes of death. Methods We evaluated paediatric deaths from January 2017 through December 2022 . A panel of experts determined the cause of death (CoD) by reviewing available data, including pathological and molecular findings from minimally invasive tissue sampling (lung tissues, blood, CSF, and nasopharyngeal swabs), clinical records, and verbal autopsies. Results Endemic HCoV were detected in the respiratory samples of 3% (n=86/3357) of enrolled decedents: 1% (n=12/204...

hnRNPM regulates #influenza A virus #replication through distinct mechanisms in #human and #avian cells: implications for cross-species transmission

ABSTRACT The eight-segmented RNA genome of influenza A virus (IAV) is transcribed and spliced into 10 major viral mRNAs in the nucleus of infected cells. Both transcription and splicing are facilitated by the host RNA polymerase II (Pol II) machinery via interactions between the viral ribonucleoprotein (vRNP) complex and various host factors. In this study, we demonstrate that IAV vRNPs recruit species-specific heterogeneous nuclear ribonucleoprotein M (hnRNPM) to support their replication in human and avian cells through distinct mechanisms. In A549 cells, human hnRNPM specifically facilitates the efficient transcription of HA, NA, M, and NS segments of WSN virus in a gene coding sequence-dependent manner. In contrast, in DF-1 cells, chicken hnRNPM restricts excessive splicing of M segment mRNA to ensure proper M2 protein production. Notably, human hnRNPM, with 34 additional amino acids compared with its chicken counterpart, fails to inhibit the M2 expression in DF-1 cells, whereas bo...

Genomic and #Clinical #Analysis of a #Fatal Human #Lyssavirus irkut Case: Evidence for a Natural Focus in the Russian Far East

Abstract In this report, we document and analyze a case in which the Irkut virus (IRKV) (Mononegavirales: Rhabdoviridae) caused a fatal human case following a bat bite in June 2021. Unfortunately, the available data did not permit a detailed taxonomic classification of the carrier bat ( Chiroptera ). The event occurred in the southwestern part of the Sikhote-Alin mountain region (Russian Far East) covered by the Ussuri taiga forest . The symptoms of the illness began with the following: fever ; pronounced psychomotor and motor agitation ; tremor of the lower jaw and tongue ; aphasia; dyslexia; and dysphagia . These rapidly developed, leading to a severe and fatal encephalitis . The patient was not vaccinated for rabies and did not receive rabies immunoglobulin. Using brain sections prepared from the deceased, molecular diagnostics were performed: immunofluorescence (polyclonal anti-rabies immunoglobulin) indicating the presence of the lyssavirus antigen ; and RT-PCR indicating traces o...

#COVID19 - Global #Situation (#WHO, D.O.N., June 28 '25)

  Situation at a glance Since mid-February 2025, according to data available from sentinel sites, global SARS-CoV-2 activity has been increasing, with the test positivity rate reaching 11%, levels that have not been observed since July 2024.  This rise is primarily observed in countries in the Eastern Mediterranean, South-East Asia, and Western Pacific regions .  Since early 2025 , global SARS-CoV-2 variant trends have slightly shifted. Circulation of LP.8.1 has been declining, and reporting of NB.1.8.1, a Variant Under Monitoring (VUM), is increasing , reaching 10.7% of global sequences reported as of mid-May.  Recent increases in SARS-CoV-2 activity are broadly consistent with levels observed during the same period last year, however, there still lacks a clear seasonality in SARS-CoV-2 circulation, and surveillance is limited.  Continued monitoring is essential . WHO advises all Member States to continue applying a risk-based, integrated approach to managing C...

#Surveillance of avian #influenza through #bird #guano in remote regions of the global south to uncover transmission dynamics

Abstract Avian influenza viruses (AIVs) pose a growing global health threat , particularly in low- and middle-income countries (LMICs), where limited surveillance capacity and under-resourced healthcare systems hinder timely detection and response. Migratory birds play a significant role in the transboundary spread of AIVs, yet data from key regions along migratory flyways remain sparse. To address these surveillance gaps, we conducted a study between December 2021 and February 2023 using fresh bird guano collected across 10 countries in the Global South . Here, we show that remote, uninhabited regions in previously unsampled areas harbor a high diversity of AIV strains , with H5N1 emerging as the most prevalent . Some of these H5N1 samples also carry mutations that may make them less responsive to the antiviral drug oseltamivir . Our findings documented the presence of AIVs in several underrepresented regions and highlighted critical transmission hotspots where viral evolution may be ...

#Cambodia's 4th #death of #H5N1 #birdflu recorded in 2025

PHNOM PENH, May 28 (Xinhua) -- An 11-year-old boy from western Cambodia's Kampong Speu province had died of H5N1 human avian influenza , becoming the fourth human death from the virus so far this year, the Ministry of Health said in a press statement released on Wednesday. "A laboratory result from the Pasteur Institute of Cambodia showed on May 27 , 2025, that the boy was positive for the H5N1 virus," the statement said. The ill-fated boy lived in Samraong Tong district's Srey Sampoung village. "According to queries , chickens and ducks near the patient's house had gotten sick and died subsequently a week before the boy fell ill," the statement said. Health authorities are looking into the source of the infection and examining any suspected cases or people who have been in contact with the victim in order to prevent an outbreak in the community, it added. The Southeast Asian country recorded a total of four human cases of H5N1 so far this year, with all...

Environmental #monitoring and spatiotemporal #trend #analysis of avian #influenza virus in #Xinjiang, 2021-2023

Abstract Background Avian influenza, a significant threat to public health , requires monitoring for the development of control strategies. This study aims to analyze the spatiotemporal distribution of avian influenza virus in the external environment of Xinjiang from 2021 to 2023, to enhance understanding of its transmission patterns and provide a scientific basis for public health response measures. Methods A total of 3913 avian-related environmental samples were collected from nine monitoring areas in Xinjiang . Sample types included poultry drinking water, meat cutting boards, cage surfaces, feces, and wastewater. Real-time RT-PCR was used to detect nucleic acid for H5, H7, and H9 subtypes. Data were statistically analyzed using Excel and SPSS, and spatial distribution was visualized through Kriging interpolation using ArcGIS. Results Among the collected samples, 810 tested positive , with an overall positivity rate of 20.70%. The H9 subtype was predominant , accounting for 85.43% ...

Novel Highly Pathogenic Avian #Influenza A #H5N1 Triple #Reassortant in #Argentina, 2025

Abstract Genomic sequencing of re-emerging highly pathogenic avian influenza A(H5N1) virus detected in Argentina in February 2025 revealed novel triple-reassortant viruses containing gene segments from Eurasian H5N1 and low pathogenic viruses from South and North American lineages . These findings underscore continued evolution and diversification of clade 2.3.4.4b H5N1 in the Americas. Source: BioRxIV,  https://www.biorxiv.org/content/10.1101/2025.05.23.655175v1 ____

Characteristics of the first confirmed case of #human #infection with #mpox virus clade Ib in #China

Abstract Mpox clade Ib is significant as it is associated with human cases and plays a key role in understanding the transmission and public health implications of mpox outbreaks. Here we present a case report of the first confirmed human infection of clade Ib in China , which occurred in December 2025 in Zhejiang Province. The case was a 28-year-old woman from South Africa who had sexual contact with an asymptomatic man from the Democratic Republic of the Congo . She presented with disseminated vesicular lesions on the extremities, face, buttocks, trunk, palms, and dorsum of the hands, but lesions were absent from the oral cavity, perineum, and anus. By the 18th day post-onset (DPO), only vesicles remained on the dorsum of the right foot and in the finger web spaces, with complete resolution by the 24th DPO. Among 59 consecutive samples collected, 55 tested positive for mpox virus . Oropharyngeal swabs turned negative by the 16th DPO, while skin lesion samples, urine samples, and scab...

Avian #Influenza in #Ireland: A Spatiotemporal, Subtype, and Host-Based Analysis (1983-2024)

Abstract Avian influenza virus (AIV) is a significant global concern, causing widespread mortality in wild birds, domestic poultry and most recently wild and domestic mammals . This study presents a retrospective analysis of AIV detections in the Republic of Ireland . Data was sourced from official surveillance databases, peer-reviewed literature and grey literature sources. Spatio-temporal, host-specific and subtype patterns were assessed using descriptive statistics, chi-square tests, linear regression and kernel density estimations. A total of 2,888 confirmed AIV detections were recorded from 25 of Ireland's 26 counties . Wild birds accounted for 98.7% of detections, with domestic birds comprising 1.3% and two detections in foxes . H5N1 was the most prevalent subtype (96.7%) followed by H5N8 and H6N1 . Spatial clustering was observed in urban areas, particularly Dublin . The highest seasonal peak occurred during summer, contrasting with traditional winter-associated patterns. Se...

Comparative #risk #assessment of spread of highly pathogenic avian #influenza #H5 viruses in French #broiler and layer sectors.

Abstract Since 2015, French poultry production is threatened almost every year by a reintroduction of highly pathogenic avian influenza H5 viruses . The duck sector was the most concerned by this crisis but other sectors such as broiler, layer and turkey were also affected by outbreaks. The objective of this work was to assess the risk of highly pathogenic avian influenza H5 virus transmission from one farm to another within the French broiler and layer production network. This study used the WOAH risk assessment framework . After drawing up a scenario tree of virus transmission from one farm to another, data were collected through a literature review or through experts' elicitation. Three questionnaires were developed according to the experts' field of expertise: avian influenza, broiler and layer sectors. The experts' estimates were combined using a beta distribution weighted by their confidence level. A Monte Carlo iteration process was used to combine the different prob...

#HK PRC SAR, Avian #Influenza #Report - Week 21 '25 (excerpts): One New #Human #H5N1 Case in #China

{Excerpts} Influenza A H5N1 Virus -- Date : 23/05/2025,  -- Location : China*, Guangxi Zhuang Autonomous Region,  -- Sex : Female,  -- Age : 53,   -- Clinical Status : Recovered,  -- Virus Subtype : H5N1. (...) Source: Centre for Health Protection, Hong Kong PRC SAR,  https://www.chp.gov.hk/files/pdf/2025_avian_influenza_report_vol21_wk21.pdf ____