#USA, DHS Reports Presumptive Positive #Human Case of Highly Pathogenic Avian #Influenza (#H5N1) in #Wisconsin

{Excerpt}

The Wisconsin Department of Health Services (DHS) has detected the first presumptive positive human case of Highly Pathogenic Avian Influenza A (H5N1), also known as bird flu, in Barron County. The human case follows an infected flock of commercial poultry identified in Barron County. The person had exposure to the infected flock. The case was identified through testing at the Wisconsin State Lab of Hygiene (WSLH) and is pending confirmation at CDC (Centers for Disease Control and Prevention).

DHS, in coordination with Barron County Health and Human Services, is monitoring farm workers who may have been exposed to the virus and has provided them with information to protect their health. The risk to the general public in Wisconsin remains low. People who work with infected animals, or have recreational exposure to them, are at higher risk.

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Source: Department of Health, https://www.dhs.wisconsin.gov/news/releases/121824.htm

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#USA, #CDC Confirms First Severe Case of #H5N1 #Birdflu in the United States

December 18, 2024-- A patient has been hospitalized with a severe case of avian influenza A(H5N1) virus ("H5N1 bird flu") infection in Louisiana. 

This marks the first instance of severe illness linked to the virus in the United States. The case was confirmed by the Centers for Disease Control and Prevention (CDC) on Friday, December 13. 

Since April 2024, there have been a total of 61 reported human cases of H5 bird flu reported in the United States.

Partial viral genome data of the H5N1 avian influenza virus that infected the patient in Louisiana indicates that the virus belongs to the D1.1 genotype related to other D1.1 viruses recently detected in wild birds and poultry in the United States and in recent human cases in British Columbia, Canada, and Washington state. This H5N1 bird flu genotype is different than the B3.13 genotype detected in dairy cows, sporadic human cases in multiple states, and some poultry outbreaks in the United States. Additional genomic sequencing and efforts to isolate virus from clinical specimens from the patient in Louisiana are underway at CDC.

While an investigation into the source of the infection in Louisiana is ongoing, it has been determined that the patient had exposure to sick and dead birds in backyard flocks. This is the first case of H5N1 bird flu in the U.S. that has been linked to exposure to a backyard flock. A sporadic case of severe H5N1 bird flu illness in a person is not unexpected; avian influenza A(H5N1) virus infection has previously been associated with severe human illness in other countries during 2024 and prior years, including illness resulting in death. No person-to-person spread of H5 bird flu has been detected. This case does not change CDC's overall assessment of the immediate risk to the public's health from H5N1 bird flu, which remains low.

This case underscores that, in addition to affected commercial poultry and dairy operations, wild birds and backyard flocks also can be a source of exposure. People with work or recreational exposures to infected animals are at higher risk of infection and should follow CDC's recommended precautions when around animals that are infected or potentially infected with H5N1 avian influenza virus. This means that backyard flock owners, hunters and other bird enthusiasts should also take precautions.

The best way to prevent H5 bird flu is to avoid exposure whenever possible. Infected birds shed avian influenza A viruses in their saliva, mucous, and feces. Other infected animals may shed avian influenza A viruses in respiratory secretions and other bodily fluids (e.g., in unpasteurized cow milk or 'raw milk').

As a general precaution, whenever possible, people should avoid contact with sick or dead animals, in particular wild birds, and poultry.

For individuals with direct/close contact with wild birds or sick or dead poultry or other animals, wear recommended personal protective equipment (PPE). Wild birds can be infected with avian influenza A viruses even if they don't look sick.

-- Do not touch surfaces or materials (e.g., animal litter or bedding material) contaminated with saliva, mucous, or animal feces from wild or domestic birds or other animals with confirmed or suspected avian influenza A virus infection.

For more information on H5 bird flu in the U.S. and CDC's response, including regularly updated case counts, visit the H5 Bird Flu: Current Situation page.

Source: US Centers for Disease Control and Prevention, https://www.cdc.gov/media/releases/2024/m1218-h5n1-flu.html

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Avian #influenza: increased spread in #poultry-dense areas at end 2024

 {Excerpt}

Abstract 

Between 21 September and 6 December 2024, 657 highly pathogenic avian influenza (HPAI) A(H5N1) and A(H5N5) virus detections were reported in domestic (341) and wild (316) birds across 27 countries in Europe. Many HPAI outbreaks in domestic birds were clustered in areas with high poultry density and characterised by secondary farm-to-farm spread. Waterfowl, particularly the mute swan, were primarily affected during this reporting period, with HPAI virus detections focused on south-eastern Europe. Notably, A(H5N5) viruses expanded their geographic and host range, resulting in a surge in detections and mortality events described in gulls and crows. No new HPAI virus detections in mammals were reported in Europe during this reporting period, but the number of dairy cattle farms reportedly affected in the United States of America (USA) rose to > 800 in 16 States, and HPAI virus was identified in two pigs in a mixed-species farm. Between 21 September and 11 December 2024, 56 new human cases with avian influenza virus infection were reported from North America (45 A(H5N1) cases), Viet Nam (one A(H5)) and China (ten A(H9N2) cases). Most of the A(H5) human cases in North America (95.6%, n = 43/45) had reported exposure to poultry, live poultry markets, or dairy cattle prior to avian influenza virus detection or onset of illness. Human infections with avian influenza viruses remain rare and no evidence of human-to-human transmission has been documented in the reporting period. The risk of infection with currently circulating avian A(H5) influenza viruses of clade 2.3.4.4b in Europe remains low for the general public in the European Union/European Economic Area (EU/EEA). The risk of infection remains lowto-moderate for those occupationally or otherwise exposed to infected animals or contaminated environments. 

©2025 European Food Safety Authority, European Centre for Disease Prevention and Control, European Union Reference Laboratory for Avian Influenza. EFSA Journal published by Wiley-VCH GmbH on behalf of European Food Safety Authority. 

Source: European Food Safety Authority, https://www.efsa.europa.eu/sites/default/files/2024-12/9204.pdf

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Detection of #Prions in Wild #Pigs (Sus scrofa) from Areas with Reported #CWD Cases, #USA

Abstract

Using a prion amplification assay, we identified prions in tissues from wild pigs (Sus scrofa) living in areas of the United States with variable chronic wasting disease (CWD) epidemiology. Our findings indicate that scavenging swine could play a role in disseminating CWD and could therefore influence its epidemiology, geographic distribution, and interspecies spread.

Source: Emerging Infectious Diseases Journal, https://wwwnc.cdc.gov/eid/article/31/1/24-0401_article

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#USA, Confirmed #human case of #H5N1 #influenza summary during 2024 #outbreak, by state and exposure source {as of Dec. 17 '24: +1 case, total now = 61}

 {Excerpt}

Exposure Source

[State - Exposure Associated with Commercial Agriculture and Related Operations: Dairy Herds (Cattle) - Poultry Farms and Culling Operations - Other Animal Exposure† - Exposure Source Unknown‡ - State Total]

1) California - 33 - 0 - 0 - 1 - 34

2) Colorado - 1 - 9 - 0 - 0 - 10

3) Louisiana - 0 - 0 - 1 - 0 - 1 {+1}

4) Michigan - 2 - 0 - 0 - 0 - 2

5) Missouri - 0 - 0 - 0 - 1 - 1

6) Oregon - 0 - 1 - 0 - 0 - 1

7) Texas - 1 - 0 - 0 - 0 - 1

8) Washington - 0 - 11 - 0 - 0 - 11

-- Source Total - 37 - 21 - 1 - 2 - 61 {+1}

NOTE: One additional case was previously detected in a poultry worker in Colorado in 2022.

{†} Exposure was related to other animals such as backyard flocks, wild birds, or other mammals

{‡} Exposure source was not able to be identified

Additional cases meeting the Council of State and Territorial Epidemiologists (CSTE) probable case definition have been reported by states: 

-- 1 case with dairy cow exposure (CA), 

-- 3 cases with poultry exposure (WA), and 

-- 2 cases with poultry exposure (AZ) and 

-- 1 case with no defined exposure (DE). 

Confirmatory testing at CDC for these cases was negative.

This table is typically updated by 5 PM EST on Mondays (for cases confirmed by CDC on Friday, Saturday, or Sunday), Wednesdays (for cases confirmed by CDC on Monday or Tuesday), and Fridays (for cases confirmed by CDC on Wednesday and Thursday). Affected states may report cases more frequently. This table was last updated on Tuesday, December 17, 2024, outside of CDC’s routine posting cadence.

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Source: US Centers for Disease Control and Prevention, https://www.cdc.gov/bird-flu/situation-summary/?CDC_AAref_Val=https://www.cdc.gov/flu/avianflu/avian-flu-summary.htm 

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Meta-Analysis of #Seroprevalence and #Prevalence of #Influenza A Viruses (Subtypes #H3N2, #H3N8, and #H1N1) in #Dogs

Abstract

Influenza A is a zoonotic disease that affects dogs, pigs, horses, poultry, and birds. In this report, a meta-analysis according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) was conducted. Studies of influenza A viruses in dogs providing prevalence or seroprevalence in any location worldwide were included. The results in this study show that the seroprevalence for the H3N8 influenza subtype was 7.96% (95% CI: 2.03–16.8, p < 0.001), for the H3N2 subtype was 7.44% (95% CI: 4.51–10.5, p < 0.001), and for the H1N1 subtype was 3.10% (95% CI: 0.890–6.01, p < 0.001). In the case of the prevalence analysis, a prevalence of 0.395% (95% CI: 0.160–2.44) for the H3N8 subtype. For the H3N2 subtype, a prevalence of 17.8% (95% CI: 6.66–32.6, p < 0.001) was found. No publication bias was observed in the studies evaluating seroprevalence in the H3N2 and H1N1 subtypes. In the H3N8 subtype, Begg’s test indicated publication bias, but Egger’s test showed no bias. It is essential to know the approximate prevalence and seroprevalence worldwide of canine influenza, so this study reports the presence of influenza subtypes in dogs, placing this species as a reservoir for human, swine, equine, and avian influenza A viruses.

Source: Animals (Basel), https://www.mdpi.com/2076-2615/14/23/3467 

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Avian #flu reported in 108 countries across five #continents, says #UN health agency

In an update on the mutating virus - known as H5N1 – Dr. Madhur Dhingra from the Food and Agriculture Organization, FAO, said that it had “spilled over into wildlife”. 

More than 500 bird species have been infected along with at least 70 mammalian species, including the endangered California condor and polar bears. 

In regions that are heavily reliant on poultry as a primary source of protein, the FAO medic insisted that avian influenza “poses a serious threat to food and nutrition security”.

Economic damage

Dr Dhingra warned that hundreds of millions of people’s livelihoods have been affected by the virus – an economic burden on farmers that could prevent them from investing in adequate biosafety measures.

Following the emergence of H5N1 influenza virus in dairy cattle, the WHO has joined calls for strengthened surveillance and biosecurity on farms, to keep animals and people safe.

The UN health agency said that in 2024, 76 people have been infected with the H5 avian influenza strain, and most were farm workers. More than 60 cases originated in the US, which has also reported outbreaks of H5 in wildlife and poultry and, more recently, in dairy cattle.

There have also been cases reported in Australia, Canada, China, Cambodia and Viet Nam.

Low risk to humans – for now

Dr. Maria Van Kerkhove, who currently serves as Director of Epidemic and Pandemic Threat Management for the WHO, said that based on the latest science, “we assess the risk of infection for the public – you and I – is currently low.”

But if you work on a farm, she cautioned – and are exposed to infected animals – “we assess the current public health risk to be low-to-moderate,” depending on the level of personal protection taken.

There is no evidence so far that the H5N1 viruses have adapted to spread between people and there has been no reported cases of human-to-human transmission.

No room for complacency

“We must remember, however, that this can change quickly,” the UN pandemic expert added, “as the virus is evolving and we must be prepared for such a scenario.”

Every case that occurs in humans must therefore be investigated thoroughly.

Dr. Van Kerkhove also stressed the importance of drinking pasturised milk – and if that’s not available, of heating milk before consumption.

“We want to reiterate the critical importance of using a One Health approach across sectors – globally, nationally, and sub-nationally -  to tackle avian influenza effectively, to minimize the risk in animals and humans,” she concluded.  

Source: United Nations, https://news.un.org/en/story/2024/12/1158286 

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#Italy, a 55-year-old man died from suspected #hemorrhagic #fever: after returning from a trip to #DRC

 {Excerpt}

He had recently returned from a trip to Congo and died on Monday evening from a suspected case of hemorrhagic fever . The victim is a 55-year-old man from Trevignano , in the province of Treviso. The news was communicated by the Public Health Hygiene Service of the Azienda Ulss 2 Marca trevigiana and diagnostic tests are underway in collaboration with the Spallanzani Institute of Rome to trace the origins of the death.

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Source: Il Fatto Quotidiano (in Italian), https://www.ilfattoquotidiano.it/2024/12/17/treviso-55enne-morto-febbre-emorragica-rientrato-congo/7808209/

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Structure-based #Design of #Chimeric #Influenza #Hemagglutinins to Elicit Cross-group #Immunity

Abstract

Antigenic variability among influenza virus strains poses a significant challenge to developing broadly protective, long-lasting vaccines. Current annual vaccines target specific strains, requiring accurate prediction for effective neutralization. Despite sequence diversity across phylogenetic groups, the hemagglutinin (HA) head domain's structure remains highly conserved. Utilizing this conservation, we designed cross-group chimeric HAs that combine antigenic surfaces from distant strains. By structure-guided transplantation of receptor-binding site (RBS) residues, we displayed an H3 RBS on an H1 HA scaffold. These chimeric immunogens elicit cross-group polyclonal responses capable of neutralizing both base and distal strains. Additionally, the chimeras integrate heterotrimeric immunogens, enhancing modular vaccine design. This approach enables the inclusion of diverse strain segments to generate broad polyclonal responses. In the future, such modular immunogens may serve as tools for evaluating immunodominance and refining immunization strategies, offering potential to bridge and enhance immune responses in individuals with pre-existing immunity. This strategy holds promise for advancing universal influenza vaccine development.

Source: BioRxIV, biorxiv.org/content/10.1101/2024.12.17.628867v1?rss=1

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#Vietnam, Epidemiological #surveillance reinforced at Noi Bai #airport to prevent a #disease that appeared in the #DRC

 {Excerpt}

According to the Hanoi Center for Disease Control (CDC), in close collaboration with international health authorities, it maintains enhanced epidemiological surveillance at Noi Bai airport to quickly detect any suspected cases and implement preventive measures adapted to the evolution of the global and local health situation.

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Source: Vietnam+, https://fr.vietnamplus.vn/surveillance-epidemiologique-renforcee-a-laeroport-de-noi-bai-pour-prevenir-une-maladie-apparue-en-rdc-post237120.vnp 

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#USA, #California recalls more raw #milk products due to #H5N1 #birdflu #contamination

 {Excerpt}

(Xinhua) 13:20, December 17, 2024

LOS ANGELES, Dec. 16 (Xinhua) -- The U.S. state of California has recalled raw milk produced and packaged by Valley Milk Simply Bottled, a local dairy company based in Stanislaus County, due to detection of bird flu virus.

The recall order came following the detection of Influenza-A H5N1 (bird flu) virus in samples taken from a raw milk bulk tank at the Valley Milk Simply Bottled dairy farm, said the California Department of Food and Agriculture (CDFA) in a release.

The order applies to all "Valley Milk Simply Bottled Raw Cow Milk" and "DESI Milk Raw Cow Milk" distributed in quart, half-gallon, and one-gallon plastic jugs with a code date marked on the container of DEC 23 2024 through DEC 30 2024.

CDFA urged consumers not to consume any product remaining in their refrigerators. No illnesses have been reported in the state yet.

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Source: People's Daily, http://en.people.cn/n3/2024/1217/c90000-20254910.html 

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The novel #H10N3 avian #influenza virus acquired #airborne #transmission among #chickens: an increasing threat to public health

ABSTRACT

Following two human infections with the H10N3 avian influenza virus (AIV) in 2021 and 2022, a third case was discovered in Yunnan, China, in 2024, raising concerns about the potential for future pandemics. Recent studies have indicated that novel H10N3 viruses are highly pathogenic in mice and can be transmitted between guinea pigs via respiratory droplets without prior adaptation. However, the biological characteristics of novel H10N3 in poultry have not been fully elucidated. Our findings revealed that H10 subtype AIVs are predominantly prevalent in waterfowl. Notably, H10N8 and H10N3 viruses that have infected humans were primarily isolated from chickens. For the first time, double basic hemagglutinin cleavage sites (motif PEIKQGR↓GL) were identified in novel H10N3 AIVs, which exhibit enhanced replication in chickens, and can be transmitted between chickens through direct contact and respiratory droplets. Animal experimental studies demonstrated that ducks are also susceptible to H10N3 viruses and that the virus is transmissible through direct contact, suggesting a greater risk of transmission and recombination. Serological studies conducted among poultry workers suggest that while the human population was largely naïve to H10N3 infection, sporadic and undetected human infections did occur, indicating a potential increasing trend. These data further emphasize the growing threat to public health posed by zoonotic H10N3 subtype AIVs.

Source: mBio, https://journals.asm.org/doi/10.1128/mbio.02363-24

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#USA, #USDA Confirms Highly Pathogenic Avian #Influenza in Backyard Non-Poultry #Flock in #Louisiana

 {Excerpt}

WASHINGTON, December 16, 2024 – The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic avian influenza (HPAI) in a non-commercial backyard flock (non-poultry) in Bossier Parish, Louisiana.  This is the first case of HPAI in domestic birds in Louisiana during this outbreak, which began in February 2022.

Samples from the flock were tested at the Louisiana Animal Disease Diagnostic Laboratory, part of the National Animal Health Laboratory Network, and confirmed at the APHIS National Veterinary Services Laboratories in Ames, Iowa.

APHIS is working closely with state animal health officials in Louisiana on a joint incident response and will provide appropriate support as requested. 

According to the U.S. Centers for Disease Control and Prevention (CDC), the public health risk associated with these avian influenza detections in birds remains low.  As a reminder, the proper handling and cooking of all poultry and eggs to an internal temperature of 165 ˚F is recommended as a general food safety precaution.

As part of existing avian influenza response plans, Federal and State partners are working jointly on additional surveillance and testing in areas around the affected flock. The United States has the strongest AI surveillance program in the world, and USDA is working with its partners to actively look for the disease in commercial poultry operations, live bird markets and in migratory wild bird populations. 

Anyone involved with poultry production from the small backyard to the large commercial producer should review their biosecurity activities to assure the health of their birds. Visit APHIS’ Defend the Flock Resource Center for materials about biosecurity, including videos, checklists, and a toolkit.

USDA will report these findings to the World Organisation for Animal Health (WOAH) as well as international trading partners. USDA also continues to communicate with trading partners to encourage adherence to WOAH standards and minimize trade impacts. WOAH trade guidelines call on countries to base trade restrictions on sound science and, whenever possible, limit restrictions to those animals and animal products within a defined region that pose a risk of spreading disease of concern. WOAH trade guidelines also call on member countries to not impose bans on the international trade of poultry commodities in response to notifications in non-poultry.

APHIS announces the first case of HPAI in commercial and backyard flocks detected in a State but does not announce subsequent detections in the State. All cases in commercial and backyard flocks are listed on the APHIS website.

In addition to practicing good biosecurity, all bird owners should prevent contact between their birds and wild birds and report sick birds or unusual bird deaths to State/Federal officials, either through their state veterinarian or through APHIS’ toll-free number at 1-866-536-7593. APHIS urges producers to consider bringing birds indoors when possible to further prevent exposures. The Animal Health Protection Act authorizes APHIS to provide indemnity payments to producers for birds and eggs that must be depopulated during a disease response. APHIS also provides compensation for disposal activities and virus elimination activities. Additional information on biosecurity for backyard flocks can be found on APHIS’ Defend the Flock webpage.

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Source: USDA, https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-highly-pathogenic-avian-influenza-backyard-non-poultry-1 

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Viral #sepsis: #diagnosis, clinical #features, #pathogenesis, and #clinical considerations

Abstract

Sepsis, characterized as life-threatening organ dysfunction resulting from dysregulated host responses to infection, remains a significant challenge in clinical practice. Despite advancements in understanding host-bacterial interactions, molecular responses, and therapeutic approaches, the mortality rate associated with sepsis has consistently ranged between 10 and 16%. This elevated mortality highlights critical gaps in our comprehension of sepsis etiology. Traditionally linked to bacterial and fungal pathogens, recent outbreaks of acute viral infections, including Middle East respiratory syndrome coronavirus (MERS-CoV), influenza virus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), among other regional epidemics, have underscored the role of viral pathogenesis in sepsis, particularly when critically ill patients exhibit classic symptoms indicative of sepsis. However, many cases of viral-induced sepsis are frequently underdiagnosed because standard evaluations typically exclude viral panels. Moreover, these viruses not only activate conventional pattern recognition receptors (PRRs) and retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) but also initiate primary antiviral pathways such as cyclic guanosine monophosphate adenosine monophosphate (GMP-AMP) synthase (cGAS)-stimulator of interferon genes (STING) signaling and interferon response mechanisms. Such activations lead to cellular stress, metabolic disturbances, and extensive cell damage that exacerbate tissue injury while leading to a spectrum of clinical manifestations. This complexity poses substantial challenges for the clinical management of affected cases. In this review, we elucidate the definition and diagnosis criteria for viral sepsis while synthesizing current knowledge regarding its etiology, epidemiology, and pathophysiology, molecular mechanisms involved therein as well as their impact on immune-mediated organ damage. Additionally, we discuss clinical considerations related to both existing therapies and advanced treatment interventions, aiming to enhance the comprehensive understanding surrounding viral sepsis.

Source: Military Medical Research, https://mmrjournal.biomedcentral.com/articles/10.1186/s40779-024-00581-0 

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From North to South: #Transmission #Dynamics of #H1N1pdm09 Swine #Influenza A Viruses in #Italy

Abstract

The influenza A H1N1pdm09 virus continues to be a significant pathogen, posing potential risks to both animal and human health due to its zoonotic potential. Italy, which has one of the largest swine populations in Europe, plays a crucial role in monitoring the evolution of influenza viruses in livestock. This study aims to address the existing knowledge gaps regarding the genetic diversity and transmission dynamics of H1N1pdm09 circulating in Italian swine populations. Utilizing whole genome sequencing and dynamic modeling, we conducted a comprehensive analysis of virus samples collected from swine farms across Italy. Our results reveal that multiple independent viral introductions have occurred into the country, with most cases resulting in self-limited infections and limited onward transmission. However, six distinct transmission clusters were identified, suggesting instances of sustained viral spread. These clusters were found across multiple regions of Italy, highlighting the broad geographic distribution of virus lineages. Our findings indicate that while many introductions led to localized containment, certain virus lineages were able to spread within specific regions of Italy. Through a detailed examination of selective pressures, we observed that most viral genes are under strong purifying selection in both swine and human hosts, as reflected by dN/dS ratios well below 1. The hemagglutinin (HA) gene exhibited a notably higher dN/dS ratio in swine (~0.28) compared to humans (~0.22), indicating slightly relaxed selection in swine. In contrast, other genes, such as neuraminidase (NA) and non-structural protein (NS), showed similarly strong purifying selection across both hosts. These results reflect a general trend of selective pressures affecting multiple viral components, rather than emphasizing specific genes. Our study emphasizes the importance of ongoing genomic surveillance in detecting viral circulation and mitigating risks to both animal and public health. Italy's efforts contribute significantly to global influenza monitoring and highlight the importance of a One Health approach that integrates human, animal, and environmental health. These findings provide essential data to inform public health policies and enhance preparedness against future zoonotic influenza outbreaks.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.12.12.628126v1?rss=1 

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High cumulative #viral titers of #influenza virus in #animals with significant disease #fatality rates indicate a potential trade-off between fatality and transmissibility

Abstract

Evaluating the trade-off hypothesis for the evolution of virulence using empirical data poses significant challenges. The hypothesis suggests that pathogens evolve to maximize transmissibility, but fatality imposes limits as there are diminishing gains in transmissibility. In this study, we analyzed a secondary dataset of influenza virus infections in ferrets (Mustela putorius furo), categorized by Hemagglutinin (HA) and Neuraminidase (NA) subtypes. Subgroups defined by the H7/N9 and H7/N7 combinations exhibited fatality rates of approximately 30% and reached cumulative viral titers close to 7.5 (log10 titer/mL). These levels represent intermediate fatality rates, as the H5/N6 and H5/N1 subgroups had higher fatality rates but reached lower cumulative viral titers. Using cumulative viral titer as a proxy for potential secondary transmissions, the analysis suggests that intermediate fatality rates are associated with higher numbers of secondary transmissions. However, there are significant uncertainties in subgroups with lower or no fatalities. Additionally, subgroups without fatalities showed substantial variability in cumulative viral titers.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.12.11.627227v1 

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#Sudan - #Equine #influenza virus (Inf. with) - Immediate notification

Virus untyped. Unspecified domestic equidae species in South Darfur.

Source: WOAH, https://wahis.woah.org/#/in-review/6097

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Pasteurized retail #dairy enables #genomic #surveillance of #H5N1 avian #influenza virus in #USA #cattle

Abstract

Highly pathogenic avian influenza (HPAI) viruses with H5 hemagglutinin (HA) genes (clade 2.3.4.4b) are causing an ongoing panzootic in wild birds. Circulation of these viruses is associated with spillover infections in multiple species of mammals, including a large, unprecedented outbreak in American dairy cattle. With limited testing of dairy herds, there is an unmet need for genomic surveillance. Infected cattle can shed high amounts of HPAI H5N1 viruses in milk, allowing detection in pasteurized retail dairy samples. Over a 2-month sampling period in one Midwestern city, we obtained dairy products processed in 20 different states. Here we demonstrate that a tiled-amplicon sequencing approach produced over 90% genome coverage at greater than 20x depth from 5 of 13 viral RNA positive samples. A combination of RT-qPCR testing and sequencing from retail dairy prod- ucts can be a useful component of a One Health framework for responding to the avian influenza outbreak in cattle.

Source: MedRxIV, https://www.medrxiv.org/content/10.1101/2024.12.12.24318872v1

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#Influenza a Virus #Detection at the #Human – #Swine Interface in #US #Midwest Swine Farms

Abstract

This study evaluated influenza A virus (IAV) detection and genetic diversity over time, specifically at the human–swine interface in breeding and nursery farms. Active surveillance was performed monthly in five swine farms in the Midwest United States targeting the employees, the prewean piglets at sow farms, and the same cohort of piglets in downstream nurseries. In addition, information was collected at enrollment for each employee and farm to assess production management practices, IAV vaccination status, diagnostic procedures, and biosecurity. Farm employee and swine samples were screened by IAV reverse transcription real-time polymerase chain reaction (RT-rtPCR), followed by IAV subtyping RT-rtPCR and whole genome sequencing on PCR-positive samples. This study showed higher positivity of IAV RNA detection in nursery pigs compared to prewean pigs, and more whole genome sequences were also obtained in the nursery phase. Surveillance of farm employees revealed two detections of H3N2 representing the 2022–2023 human IAV season, confirming the presence of influenza in farm employees while present at work, and thus highlighting the importance of biosecurity measures at the human–swine interface. This study highlights the importance of routine active surveillance to understand the dynamics of IAV at the farm level in both farm employees and swine.

Source: Viruses, https://www.mdpi.com/1999-4915/16/12/1921

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#USA, Two more #human cases of #H5N1 #birdflu reported in #California

Two cases of bird flu have been reported in San Joaquin County, California, local health officials said.

According to a press release issued Friday and reported by the Sacramento Bee, health officials with San Joaquin County Public Health Services said both cases were farm workers who were exposed to infected animals. Both people are showing mild symptoms and are recovering, officials said, adding that there are 34 total confirmed cases across California.

In a warning posted on Facebook, health officials said bird flu was “spreading in several farms such as poultry and cattle” and urged residents to take precautions to prevent the spread of the disease.

Precautions include the use of protective equipment when handling poultry, dairy cattle or other animals that may be infected, and when handling raw and unpasteurized milk.

(...) There are currently 60 confirmed cases of bird flu in the country. While most of the cases are in California, other states with confirmed cases include Colorado, Michigan, Missouri, Oregon, Texas and Washington, according to the Centers for Disease Control and Prevention.

(...)

Source: Netizen Media, original text in Bahasa Indonesia, LINK

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