Wastewater surveillance for avian influenza: national patterns of detection and relationship with reported outbreaks and infections

Abstract

Background. 

Influenza A virus (IAV) is a major cause of morbidity and mortality globally, causing seasonal influenza in humans and infecting birds and some mammals. In 2024, IAV H5N1 highly pathogenic avian influenza (HPAI) in the United States moved into cattle. While the outbreak is currently of low risk to the general public, there is an urgent need to monitor the disease and prevent spread. 

Methods. 

We conducted a nationwide study evaluating the relationship between H5 hemagglutinin gene RNA concentrations in wastewater and reported outbreaks of IAV H5N1 in animals and humans. We utilized an H5-specific droplet digital RT-PCR test to quantify H5 RNA in wastewater in 40 states across the United States, and 1) examined the temporal association between outbreaks and wastewater detections and 2) utilized linear mixed models (LMM) to determine the relationship between measurements in wastewater and outbreak-related factors in the local area. 

Results. 

We find that there is a significant temporal association between wastewater H5 detections and the incidence of outbreaks in poultry and wild birds, but not in cattle or with human infections. However outbreaks tended to occur at the same time across populations - wild bird detections were also associated with H5N1 in herds, poultry, and humans. Utilizing a LMM, we find that for individual sites, there is a relationship between H5 measurements in wastewater and both poultry outbreaks and the presence of dairy industry locally, but that there was either no relationship or a negative relationship with H5 measurements and either combined systems that accept storm water or those with detection of H5 in wild birds. 

Conclusions. 

The study highlights how wastewater monitoring can supplement traditional surveillance, providing vital data that reflects public health threats. The findings underscore the potential of scaled wastewater surveillance as a proactive tool in monitoring and managing future outbreaks.

Source: MedRxIV, https://www.medrxiv.org/content/10.1101/2025.05.06.25327100v1

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A Highly Protective Clade 1 and 2 Cross-Reactive #Pandemic #Influenza Virus #Vaccine Based on a 4th Generation Fully Deleted Adenoviral Vector of a Rare Serotype

Abstract

The GreVac vaccine technology was created as a fast and flexible plug-and-play vaccine platform based on a 4th generation architecture of fully deleted (fd) helper virus independent (hi) adenoviral (Ad) vectors. For the initial proof-of-principle studies, we at Greffex had engineered an avian influenza vaccine, which delivered a transgene expression cassette for an avian influenza virus H5 hemagglutinin and N1 neuraminidase genes in a capsid of the common human Ad serotype 5 (Ad5). This vaccine proved highly immunogenic and protective in mice. These studies revealed that intramuscular (i.m.) delivery proved more efficient than subcutaneous (s.c.) or intranasal (i.n.) routes. In the human population, pre-exposure to the Ad5 virus is common. To minimize interference by pre-existing anti-Ad5 immunities, we created a new GreVac-based avian influenza vaccine, in which the fd Ad genome was packaged into a capsid of the rare human Ad serotype 6 (Ad6). We now report that at very low doses, the resulting GreFluVie6 vaccine given i.m. fully protected mice and ferrets against lethal challenges with the clade 1 A/Vietnam/1203/2004 avian influenza virus associated with induction of potent immune cellular and humoral immune responses. The recipient serum antibodies strongly crossreacted with clade 2.1.3.2 (A/Indonesia/05/2005) and clade 2.3.4.4b H5 hemagglutinins.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.04.30.651579v1

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Unique Phenomenon of #H5 Highly Pathogenic Avian #Influenza Virus in #China: Co-circulation of Clade 2.3.4.4b #H5N1 and #H5N6 results in diversity of H5 Virus

Abstract

Recently, Clade 2.3.4.4b H5N1 virus has been widely prevalent globally. Although no outbreaks of Avian Influenza have occurred in poultry in China recently, Clade 2.3.4.4b H5 virus can still be isolated from wild birds, live poultry markets and environment, indicating the ongoing co-circulation of H5N1 and H5N6 viruses. In this study, phylogenetic analysis of global Clade 2.3.4.4b viruses and 20 laboratory-isolated H5 strains revealed that Chinese H5N1 and H5N6 viruses since 2021 cluster into two distinct groups, G-I and G-II. Bayesian phylodynamic analysis reveals that G-I H5N6 virus has become an endemic virus in China. In contrast, G-II H5N1 virus, with South China as its main epicentre, has been disseminated in China and its surrounding countries, with its transmission more reliant on the connections of wild birds and waterfowl. Reassortment analysis indicates that since 2023, Clade 2.3.4.4b H5 viruses isolated in China have formed seven genotypes. The genome of H5 viruses has undergone changes compared to those previously prevalent in China. Animal experiments have shown that prevalent H5 viruses exhibit significant lethality in chickens. Additionally, certain H5 viruses have shown the capability of systemic replication in mice. It is noted that H5N6 viruses with HA genes derived from H5N1 viruses demonstrate stronger virulence and pathogenicity in chickens and mice compared to G-I H5N6 viruses. Our study indicates that the co-circulation of H5N1 and H5N6 viruses in China has increased the diversity of H5 viruses, making continuous surveillance of H5 viruses essential.

Source: Emerging Microbes and Infections, https://www.tandfonline.com/doi/full/10.1080/22221751.2025.2502005

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Single-dose replicon #RNA #Sudan virus #vaccine uniformly protects female guinea pigs from disease

Abstract

The Sudan virus (SUDV) outbreaks in Uganda in 2022 and 2025 created public health concerns in-country and the entire East African region. There are currently no licensed countermeasures against SUDV. We developed a SUDV vaccine candidate based on a nanocarrier (LIONTM) complexed with an alphavirus-based replicon RNA. Here, we compare the protective efficacy of the LION-SUDV vaccine either encoding the SUDV glycoprotein (GP) alone or in combination with the Ebola virus (EBOV) GP (LION-Combination). A LION-EBOV vaccine which is protective against EBOV was also included to determine the potential for cross-protection against SUDV infection. Single-dose vaccinations were conducted three weeks before challenge with a lethal dose of guinea pig-adapted SUDV using a female guinea pig disease model. We demonstrate 100% survival and protection with the LION-SUDV and the LION-Combination vaccines, while the LION-EBOV vaccine achieved 50% protection. Antigen-specific humoral responses correlate with decreased virus replication and survival. This result warrants further studies in larger animal species to ensure that protective efficacy is maintained with the single-dose LION-SUDV vaccine.

Source: Nature Communications, https://www.nature.com/articles/s41467-025-59560-1

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Antiviral #CD4+ T and myeloid cell responses to #influenza #vaccines are attenuated in older #adults

Abstract

Recent influenza vaccine formulations have improved the magnitude of B-cell antibody responses in older adults; however, older adults remain significantly at risk for severe influenza-related illness. Although antibodies are an important metric of vaccine effectiveness, they only represent one aspect of the immune response. In this study, we combined in vitro and ex vivo assays with human samples to investigate B, CD4+ T, and myeloid cell responses to influenza vaccine antigens. We found that older adults mounted equivalent antibody titers to younger adults but had fewer influenza-specific CD4+ T cells and reduced antiviral-associated T helper cell populations. Single-cell transcriptomics revealed that older adults had attenuated interferon transcriptional signatures in T helper and myeloid cell subsets. These data suggest that with aging, transcriptional programming alterations in myeloid cells contribute to reduced antiviral T cell responses, and formulating vaccines tailored to myeloid responses is necessary to improve outcomes in older adults.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.04.30.651528v1?rss=1

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#Influenza #H1N1pdm09 Virus #Resistance to #Baloxavir, #Oseltamivir and Sialic Acid Mimetics in Single and Dual #therapies: Insights from Human Airway Epithelia and Murine Models

Highlights

• Reconstituted human airway epithelia (HAE) are more effective than cell lines or mouse models for generating and predicting resistance-conferring mutations.

• The resistance barrier of oseltamivir is superior to baloxavir or HA targeting compounds in HAE or mouse model.

• HA-targeting therapeutics quickly led to resistant HA mutations without compromising viral fitness.

• A baloxavir-resistant virus with PA mutations E23G and C241Y was isolated in HAE.

• Combined therapy using clinical antiviral compounsd and HA-targeting compounds did not prevent the emergence of HA mutations.

Abstract

Influenza viruses pose a significant threat due to annual epidemics and pandemic potential. Resistance to current antivirals underscores the need for new drugs and strategies to prevent its emergence. We previously developed two novel HA-targeting compounds (CD-6’SLN and CD-SA) with demonstrated efficacy against influenza A and B strains. Here, we compared their resistance barrier to that of FDA-approved oseltamivir (OS) and baloxavir marboxil (BXM). We established a resistance testing assay in human airway epithelia (HAE) and in mice. We also evaluated the impact of combination therapies on resistance emergence. In HAE, highly reduced inhibition (HRI) by CD-6’SLN and CD-SA occurred within 2 and 4 weeks respectively without fitness loss, while reduced inhibition (RI) by baloxavir acid (BXA) emerged within 4 weeks. No reduction of susceptibility to OS was observed in the same time frame. Of note, emergence of RI by CD-SA was not delayed in BXA/CD-SA co-treatment, and slightly reduced upon OS/CD-SA co-treatment. In mice, RI by CD-SA was observed after 8 passages in one of three mice treated with OS/CD-SA, but not in mice with single therapies. This study demonstrates that (1) HAE represents a relevant model to detect emergence of resistance and (2) HA-targeting compounds are prone to induce resistance followed by BXA and OS. Importantly, combination of clinically available antivirals and HA-targeting compounds did not prevent the emergence of variants with HA substitutions. Additional research is needed to develop anti-influenza antivirals with high resistance barrier and compounds should be tested in HAE before moving to animal experimentation.

Source: Antiviral Research, https://www.sciencedirect.com/science/article/abs/pii/S0166354225001007?via%3Dihub

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Return of the Biennial #Circulation of #Enterovirus D68 in #Colorado #Children in 2024 Following the Large 2022 #Outbreak

Abstract

Enterovirus D68 (EV-D68) caused large biennial cyclical outbreaks of respiratory disease and cases of acute flaccid myelitis from 2014 to 2018 in the USA. An anticipated outbreak did not occur in 2020, likely due to non-pharmaceutical interventions targeting the COVID-19 pandemic. A large respiratory disease outbreak occurred again in 2022, but uncertainty remained regarding if circulation of EV-D68 would return to the pre-pandemic patterns. We conducted prospective active surveillance of clinical respiratory specimens from Colorado children for EV-D68 in 2023 and 2024. A subset of residual specimens positive for rhinovirus/enterovirus (RV/EV) were tested for EV-D68 via a validated in-house EV-D68 reverse transcription–PCR assay. During epi weeks 18–44 in 2023, 525 residual specimens positive for RV/EV all tested negative for EV-D68. In 2024, during epi weeks 18–44, 10 (1.8%) of the 546 RV/EV-positive specimens were EV-D68-positive. The EV-D68-positive cases were predominantly young children (median age 4.8 years) receiving treatment with asthma medications. Following the 2022 EV-D68 outbreak, an anticipated outbreak did not occur in 2023. While EV-D68 was detected in 2024, the number of cases was not as significant as in prior outbreak years. Continued surveillance for EV-D68 will be important to understand the future dynamics of EV-D68 circulation and prepare for future outbreaks.

Source: Viruses, https://www.mdpi.com/1999-4915/17/5/673

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Genesis and Spread of Novel Highly Pathogenic Avian #Influenza A(#H5N1) Clade 2.3.4.4b Virus #Genotype EA-2023-DG #Reassortant, Western #Europe

Abstract

In Europe, highly pathogenic avian influenza (HPAI) virus circulates in avian wildlife, undergoing frequent reassortment, sporadic introductions in domestic birds, and spillover to mammals. An H5N1 clade 2.3.4.4b reassortant, EA-2023-DG, affecting wild and domestic birds was detected in western Europe in November 2023. Six of its RNA segments came from the EA-2021-AB genotype, but the polymerase basic 2 and polymerase acidic segments originated from low pathogenicity avian influenza viruses. Discrete phylogeographic analyses of concatenated genomes and single polymerase basic 2 and polymerase acidic segments suggested reassortment in summer 2023 near the southwestern Baltic Sea. Subsequent continuous phylogeographic analysis of all concatenated EA-2023-DG genomes highlighted circulation in northwestern Europe until June 2024 and long-distance dispersal toward France, Norway, England, Slovakia, Switzerland, and Austria. Those results illustrate the value of phylodynamic approaches to investigate emergence of novel avian influenza virus variants, trace their subsequent dispersal history, and provide vital clues for informing outbreak prevention and intervention policies.

Source: US Centers for Disease Control and Prevention, https://wwwnc.cdc.gov/eid/article/31/6/24-1870_article

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Intranasally administered whole virion inactivated #vaccine against clade 2.3.4.4b #H5N1 #influenza virus with optimized #antigen and increased cross-protection

Abstract

The global spread, frequent antigenic changes, and pandemic potential of clade 2.3.4.4b highly pathogenic avian influenza H5N1 underscore the urgent need for robust cross-protective vaccines. Here, we developed a clade 2.3.4.4b H5N1 whole inactivated virus (WIV) vaccine strain with improved structural stability, productivity, and safety. By analyzing the evolutionary trends of clade 2.3.4.4b H5N1 viruses, we identified a key mutation (R90K) that increases heat stability while preserving antigenicity. Additionally, the PB2 gene of PR8 was replaced with a prototypical avian PB2 gene to increase replication efficiency in embryonated chicken eggs and reduce replication efficiency in mammalian cells, thereby improving productivity and biosafety. We found that our optimized clade 2.3.4.4b H5N1 vaccine strain (22W_KY), inactivated with binary ethylenimine (BEI), had superior antigen internalization into respiratory epithelial cells compared to those inactivated with formaldehyde or beta-propiolactone. Following intranasal administration to mice, the BEI-inactivated 22W_KY also elicited significantly stronger systemic IgG, mucosal IgA, and T-cell responses, especially in the lungs. Protective efficacy studies revealed that the BEI-inactivated 22W_KY vaccine provided complete protection against heterologous viral challenges and significant protection against heterosubtypic viral challenges, with no weight loss and complete suppression of the viral load in the respiratory tract in 2 of 3 mice. These results indicate that the BEI-inactivated 22W_KY vaccine could serve as a promising candidate for a safe, stable, cost-efficient, and broadly protective intranasal influenza vaccine against zoonotic and pandemic threats.

Source: Virology Journal, https://virologyj.biomedcentral.com/articles/10.1186/s12985-025-02760-4

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History of Mass Transportation: The FS ALn 668 Autorail

 

Distributed via CC (Creative Common), Source: Wikipedia: https://it.wikipedia.org/wiki/Automotrice_FS_ALn_668

Credit: Di Phil Richards - Flickr: 14.11.95 Palermo Centrale ALn668.1609, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=21836099

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Avian #Influenza A(#H5N1) Isolated from Dairy #Farm #Worker, #Michigan

Abstract

Influenza A(H5N1) viruses have been detected in US dairy cow herds since 2024. We assessed the pathogenesis, transmission, and airborne release of A/Michigan/90/2024, an H5N1 isolate from a dairy farm worker in Michigan, in the ferret model. Results show this virus caused airborne transmission with moderate pathogenicity, including limited extrapulmonary spread, without lethality.

Highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b viruses have displayed unprecedented global spread among wild birds leading to numerous spillover infections in mammalian species. Of note, outbreaks in dairy cattle and gallinaceous birds have resulted in human infections in the United States during 2024–2025 (1). Increased frequency of H5N1 viruses crossing species barriers has caused concern that the avian influenza viruses are adapting to mammals. A critical component of influenza pandemic preparedness is early identification of emerging novel influenza viruses that cause disease and transmit efficiently in humans. A clade 2.3.4.4b H5N1 virus, A/Michigan/90/2024 (MI90), genotype B3.13, was isolated from a conjunctival swab specimen collected from a human patient in Michigan with conjunctivitis after exposure to infected cattle (2,3). In this article, we report the pathogenesis, transmission, and airborne exhalation of MI90 virus in ferrets, the standard animal model for influenza virus risk assessments (4).

We inoculated 18 ferrets with MI90 virus as previously described (5,6). We euthanized 3 ferrets on 3 and 5 days postinoculation (dpi) to assess virus spread in tissues. We used 6 ferrets to assess transmission in a cohoused, direct contact setting as a direct contact transmission model and through the air in the absence of direct or indirect contact as a respiratory droplet transmission model. We paired each ferret with a naive contact, as previously described (4). We observed clinical manifestations daily and collected nasal wash (NW), conjunctival, and rectal swab samples every 2 days postinoculation or postcontact. We confirmed transmission by testing for seroconversion to homologous virus in the contact animals.

Although all MI90-infected ferrets survived the 21-day study, we noted moderate disease. In inoculated ferrets, the mean maximum weight loss was 9.8%, fever (1.8°C above baseline) and lethargy were transient, and nasal and ocular discharge and sneezing were evident on days 4–9 dpi (Table). We detected virus 3 dpi primarily in respiratory tract tissues; titers were highest in ethmoid turbinate samples (7.4 log10 PFU/mL) and at low levels in brain and gastrointestinal tissues. We observed similar results in tissues collected 5 dpi.

(...)

During the direct contact transmission experiment, inoculated ferrets shed virus in NW that peaked at 4.7–5.4 log10 PFU/mL at 1–5 dpi (Figure, panel A). Four of 6 cohoused contact animals had virus in NW (peak 2.5–4.9 log10 PFU/mL) at 5–7 days postcontact, whereas all 6 contact animals had viral RNA detected (3.6–7.7 log10 copies/mL) in NW (7) and seroconverted to MI90 virus, indicating that transmission was 100% (6/6 animals). In the respiratory droplet transmission experiment, NW collected from inoculated animals peaked 2.6–4.8 log10 PFU/mL at 1–3 dpi, whereas 3/6 contact ferrets had detectable virus in NW by day 7 postcontact (peak 2.6–4.8 log10 PFU/mL; days 9–11 postcontact) (Figure, panel B) as well as viral RNA (6.7–8.2 log10 copies/mL), and seroconverted, confirming transmission through the air in 50% of ferrets (3/6). We also detected infectious virus in conjunctival and rectal samples from inoculated animals, but only from 2 contact animals (Table).

To further evaluate the level of virus exhaled by MI90-inoculated ferrets and the potential for airborne transmission, we collected aerosol samples 1 time each day at 1–5 dpi for 1 hour from the 3 ferrets that were euthanized at 5 dpi. Air samples were analyzed for infectious virus and viral RNA by using the BC251 cyclone-based sampler (kindly provided by Dr. William Lindsley, National Institute for Occupational Safety and Health) and the SPOT water condensation sampler (Aerosol Devices, https://aerosoldevices.comExternal Link), as described previously (8) (Figure, panel D). The highest mean titer of virus was detected at 2 dpi in NW collected from all 3 inoculated ferrets (6.5 log10 PFU/mL) (Figure, panel C). Airborne virus was highest at 3 dpi as measured in both samplers, up to 133 and 41 PFU/hour, supporting transmission observed in both contact models within 3–5 days after exposure.

Overall, MI90 virus displayed reduced virulence in ferrets compared to another H5N1 virus isolated from a dairy farm worker in Texas (8,9); the Texas virus possesses a genetic marker in the polymerase basic 2 protein (E627K), known for enhanced replication and pathogenesis in mammals. At this position, MI90 encodes 627E, like most other viruses isolated from cattle, and contains polymerase basic 2 M631L, which is associated with mammal adaptation (3,9). In addition, polymerase acidic 142N/E has been linked to increased virulence in mice (10); the Texas virus has an E and MI90 virus has a K at this position. Both viruses have identical hemagglutinin sequences associated with receptor binding and the multi-basic cleavage site. Despite differences in virulence, both viruses transmitted in the ferret model with similar proficiency and levels of airborne virus.

Because avian H5N1 viruses cross the species barrier and adapt to dairy cattle, each associated human infection presents further opportunity for mammal adaption. This potential poses an ongoing threat to public health and requires continual surveillance and risk assessment of emerging viruses to improve our ability to predict and prepare for the next influenza pandemic.

Dr. Brock is a microbiologist in the Influenza Division, National Center for Immunization and Respiratory Diseases, at the Centers for Disease Control and Prevention. Her research interests include the pathogenicity, transmissibility, and host response associated with emerging strains of influenza virus.

Source: US Centers for Disease Control and Prevention, https://wwwnc.cdc.gov/eid/article/31/6/25-0386_article

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Introducing a #framework for within-host #dynamics and #mutations modelling of #H5N1 #influenza infection in #humans

Abstract

Avian influenza A(H5N1) poses a public health risk due to its pandemic potential should the virus mutate to become human-to-human transmissible. To date, reported influenza A(H5N1) human cases have typically occurred in the lower respiratory tract with a high case fatality rate. There is prior evidence of some influenza A(H5N1) strains being a small number of amino acid mutations away from achieving droplet transmissibility, possibly allowing them to be spread between humans. We present a mechanistic within-host influenza A(H5N1) infection model, novel for its explicit consideration of the biological differences between the upper and lower respiratory tracts. We then estimate a distribution of viral lifespans and effective replication rates in human H5N1 influenza cases. By combining our within-host model with a viral mutation model, we determine the probability of an infected individual generating a droplet transmissible strain of influenza A(H5N1) through mutation. For three mutations, we found a peak probability of approximately 10-3 that a human case of H5N1 influenza produces at least one virion during the infectious period. Our findings provide insights into the risk of differing infectious pathways of influenza A(H5N1) (namely avian-human vs avian-mammal-human routes), demonstrating the three-mutation pathway being a cause of concern in human cases.

Source: MedRxIV, https://www.medrxiv.org/content/10.1101/2024.09.01.24312235v4

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#Coronavirus Disease Research #References (by AMEDEO, May 3 '25)

 

Ann Intern Med

1. BILINSKI A, Emanuel N, Ciaranello A
   Sins of Omission: Model-Based Estimates of the Health Effects of Excluding Pregnant Participants From Randomized Controlled Trials.
   Ann Intern Med. 2025 Apr 29. doi: 10.7326/ANNALS-24-00689.
   PubMed         Abstract available
   
   
2. YEK C, Mancera AG, Diao G, Walker M, et al
   Impact of the COVID-19 Pandemic on Antibiotic Resistant Infection Burden in U.S. Hospitals : Retrospective Cohort Study of Trends and Risk Factors.
   Ann Intern Med. 2025 Apr 29. doi: 10.7326/ANNALS-24-03078.
   PubMed         Abstract available
   
   
3. RIDDLER SA, Moodie Z, Clark J, Yen C, et al
   High Frequency of Chronic Urticaria Following an Investigational HIV-1 BG505 MD39.3 Trimer mRNA Vaccine in a Phase 1, Randomized, Open-Label Clinical Trial (HVTN 302).
   Ann Intern Med. 2025 Apr 29. doi: 10.7326/ANNALS-24-02701.
   PubMed         Abstract available
   
   
4. KIM D, Danpanichkul P, Wijarnpreecha K, Cholankeril G, et al
   Trends in Mortality From Chronic Liver Disease Before, During, and After the COVID-19 Pandemic, 2015 to 2023.
   Ann Intern Med. 2025 Apr 29. doi: 10.7326/ANNALS-24-03218.
   PubMed        
   
   

   
   BMJ

5. YUEN ASC, Chen B, Chan AYL, Hayes JF, et al
   Use of gabapentinoid treatment and the risk of self-harm: population based self-controlled case series study.
   BMJ. 2025;389:e081627.
   PubMed         Abstract available
   
   

   
   Clin Infect Dis

6. CHRISTENSEN A, Nelson Z, Gustafson S, Stoecker R, et al
   Into the Unknown: Practical Remdesivir Restriction in the Era of Widespread SARS-CoV-2 Seropositivity.
   Clin Infect Dis. 2025 Apr 25:ciaf217. doi: 10.1093.
   PubMed         Abstract available
   
   
7. JONES KM, Greene MT, Meddings J, Mantey J, et al
   Impact of a Collaboration-Focused Intervention to Prevent Healthcare-Associated Infections Before and During the Coronavirus Disease 2019 Pandemic.
   Clin Infect Dis. 2025 Apr 29:ciaf122. doi: 10.1093.
   PubMed         Abstract available
   
   

   
   Emerg Infect Dis

8. SPENCER BR, Akinseye A, Grebe E, Stone M, et al
   Self-Reported SARS-CoV-2 Infections among National Blood Donor Cohort, United States, 2020-2022.
   Emerg Infect Dis. 2025;31:1006-1009.
   PubMed         Abstract available
   
   
9. GREBE E, Chacreton D, Stone M, Spencer BR, et al
   Detection of SARS-CoV-2 Reinfections Using Nucleocapsid Antibody Boosting.
   Emerg Infect Dis. 2025;31:958-966.
   PubMed         Abstract available
   
   

   
   Infect Control Hosp Epidemiol

10. NGAI V, Hsi JB, Singh RD, Mitchell JE, et al
    COVID-19 prevention training with video-based feedback in nursing homes: impact on staff safety behaviors.
    Infect Control Hosp Epidemiol. 2025 Apr 28:1-8. doi: 10.1017/ice.2025.
    PubMed         Abstract available
    
    

    
    Intensive Care Med

11. PETTENUZZO T, Balzani E, Sella N, Giani M, et al
    Prone positioning during veno-venous extracorporeal membrane oxygenation: a systematic review and meta-analysis.
    Intensive Care Med. 2025 Apr 29. doi: 10.1007/s00134-025-07877.
    PubMed         Abstract available
    
    
12. ESPERATTI M, Fuentes N, Olmos M
    Optimizing non-intubated respiratory support in COVID-19: evaluating the impact of bundle of care strategy on awake prone positioning tolerance. Author's reply.
    Intensive Care Med. 2025 Apr 29. doi: 10.1007/s00134-025-07904.
    PubMed        
    
    

    
    J Infect

13. DAHL TB, Aftab F, Prebensen C, Berdal JE, et al
    Imidazole propionate is increased in severe COVID-19 and correlates with cardiac involvement.
    J Infect. 2025;90:106494.
    PubMed        
    
    
14. OVERTON CE, Fyles M, Mellor J, Paton RS, et al
    SARS-CoV-2 test sensitivity and duration of positivity in the UK during the 2023/2024 Winter: A prospective cohort study based on self-reported data.
    J Infect. 2025;90:106485.
    PubMed         Abstract available
    
    

    
    J Med Virol

15. MESSALI S, Bertelli A, Dotta L, Giovanetti M, et al
    Outbreak of Enterovirus D68 in Young Children, Brescia, Italy, August to November 2024.
    J Med Virol. 2025;97:e70372.
    PubMed         Abstract available
    
    
16. TRIFONOV G, Buscher E, Fistera D, Kill C, et al
    Disease Burden of RSV Infection in Adult Patients in Comparison to Influenza Virus Infection.
    J Med Virol. 2025;97:e70373.
    PubMed         Abstract available
    
    

    
    J Virol

17. SUN H, Yang Q, Zhang Y, Cui S, et al
    Syntaxin-6 restricts SARS-CoV-2 infection by facilitating virus trafficking to autophagosomes.
    J Virol. 2025 Apr 25:e0000225. doi: 10.1128/jvi.00002.
    PubMed         Abstract available
    
    
18. NEGI V, Kuhn RJ
    A BSL-2 chimeric system designed to screen SARS-CoV-2 E protein ion channel inhibitors.
    J Virol. 2025 Apr 30:e0225224. doi: 10.1128/jvi.02252.
    PubMed         Abstract available
    
    
19. ZHANG S, Xu C-L, Wang J, Xiong X, et al
    Spike proteins of coronaviruses activate mast cells for degranulation via stimulating Src/PI3K/AKT/Ca(2+) intracellular signaling cascade.
    J Virol. 2025 Apr 30:e0007825. doi: 10.1128/jvi.00078.
    PubMed         Abstract available
    
    

    
    JAMA

20. KIANG MV, Bubar KM, Maldonado Y, Hotez PJ, et al
    Modeling Reemergence of Vaccine-Eliminated Infectious Diseases Under Declining Vaccination in the US.
    JAMA. 2025 Apr 24. doi: 10.1001/jama.2025.6495.
    PubMed         Abstract available
    
    

    
    Nature

21. WANG N, Ji W, Jiao H, Veit M, et al
    A MERS-CoV-like mink coronavirus uses ACE2 as entry receptor.
    Nature. 2025 Apr 30. doi: 10.1038/s41586-025-09007.
    PubMed         Abstract available
    

#Influenza and Other Respiratory Viruses Research #References (by AMEDEO, May 3 '25)

 

Arch Virol

1. SVYATCHENKO SV, Boldyrev ND, Panova AS, Kolosova NP, et al
   Seroprevalence of anti-influenza antibodies in humans and characterization of seasonal influenza viruses isolated in Russia during the 2023-2024 flu season.
   Arch Virol. 2025;170:118.
   PubMed         Abstract available
   
   

   
   Biochem Biophys Res Commun

2. CHU X, Yang Y, Guo H, Ji X, et al
   SARS-CoV-2 NSP2 specifically interacts with cellular protein SmgGDS.
   Biochem Biophys Res Commun. 2025;764:151828.
   PubMed         Abstract available
   
   
3. ZHANG YH, Su AM, Hou XM
   Structural and functional insights into the SARS-CoV-2 SUD domain and its interaction with RNA G-Quadruplexes.
   Biochem Biophys Res Commun. 2025;764:151817.
   PubMed         Abstract available
   
   

   
   Epidemiol Infect

4. STERIAN M, Naganathan T, Corrin T, Waddell L, et al
   Evidence on the associations and safety of COVID-19 vaccination and post COVID-19 condition: an updated living systematic review.
   Epidemiol Infect. 2025;153:e62.
   PubMed         Abstract available
   
   

   
   J Gen Virol

5. ARANDA AJ, Aguilar-Tipacamu G, Perez DR, Banuelos-Hernandez B, et al
   Emergence, migration and spreading of the high pathogenicity avian influenza virus H5NX of the Gs/Gd lineage into America.
   J Gen Virol. 2025;106:002081.
   PubMed         Abstract available
   
   

   
   J Infect

6. CARSTENS G, Kozanli E, Bulsink K, McDonald S, et al
   Co-infection dynamics of SARS-CoV-2 and respiratory viruses in the 2022/2023 respiratory season in the Netherlands.
   J Infect. 2025 Mar 21:106474. doi: 10.1016/j.jinf.2025.106474.
   PubMed         Abstract available
   
   
7. WARD T, Paton RS, Overton CE, Mellor J, et al
   Understanding the Effectiveness of the Comirnaty Monovalent and Bivalent Vaccines During the Winter Coronavirus (COVID-19) Infection Survey.
   J Infect. 2025 Mar 5:106461. doi: 10.1016/j.jinf.2025.106461.
   PubMed         Abstract available
   
   

   
   Pediatrics

8. LOVEDAY T, da Hora C, Wells R, Chorny L, et al
   11-Year-Old Boy With B-ALL-Induced Hypereosinophilic Syndrome Presenting as Acute Encephalopathy.
   Pediatrics. 2025;155:e2024068064.
   PubMed         Abstract available
   
   
9. BAHADIR Z, Narayan P, Wolters R, Permar SR, et al
   Monoclonal Antibodies for Pediatric Viral Disease Prevention and Treatment.
   Pediatrics. 2025;155:e2024068690.
   PubMed         Abstract available
   
   
10. ZHANG L, Wang Y, Berger LM
    State-Based Eviction Moratoria and Child Maltreatment During the COVID-19 Pandemic.
    Pediatrics. 2025;155:e2024068174.
    PubMed         Abstract available
    
    
11. BANDELL A, Giles L, Cervelo Bouzo P, Sibbring GC, et al
    Safety of LAIV Vaccination in Asthma or Wheeze: A Systematic Review and GRADE Assessment.
    Pediatrics. 2025 Apr 24:e2024068459. doi: 10.1542/peds.2024-068459.
    PubMed         Abstract available
    
    

    
    PLoS Biol

12. KUBINSKI HC, Despres HW, Johnson BA, Schmidt MM, et al
    Variant mutation G215C in SARS-CoV-2 nucleocapsid enhances viral infection via altered genomic encapsidation.
    PLoS Biol. 2025;23:e3003115.
    PubMed         Abstract available
    
    

    
    PLoS Comput Biol

13. HODCROFT EB, Wohlfender MS, Neher RA, Riou J, et al
    Estimating Re and overdispersion in secondary cases from the size of identical sequence clusters of SARS-CoV-2.
    PLoS Comput Biol. 2025;21:e1012960.
    PubMed         Abstract available
    
    

    
    PLoS One

14. WITEK TJ JR, Sheikhan NY, Tran A
    Sensory effects of COVID-19 in wine professionals.
    PLoS One. 2025;20:e0321502.
    PubMed         Abstract available
    
    
15. MARSIGLIA MD, Bianchi S, Bai F, Tincati C, et al
    Effectiveness of Anti-SARS-CoV-2 monoclonal antibodies in real-life: RNAemia and clinical outcomes in high-risk COVID-19 patients.
    PLoS One. 2025;20:e0321356.
    PubMed         Abstract available
    
    
16. VANOUDENHOVE J, Liu Y, Nelakanti R, Kim D, et al
    Impact of memory T cells on SARS-CoV-2 vaccine response in hematopoietic stem cell transplant.
    PLoS One. 2025;20:e0320744.
    PubMed         Abstract available
    
    
17. GHIROTTO L, De Panfilis L, Perin M, Miraglia Raineri A, et al
    Psycho-oncology practice for cancer patients during the pandemic lockdown in Italy: A qualitative mixed-method study with psychotherapists.
    PLoS One. 2025;20:e0318241.
    PubMed         Abstract available
    
    
18. MOTIEI M, Hassanzadeh Rad A, Badeli H, Bayat R, et al
    Hospitalization dynamics during COVID-19: Insights into disease trends and patient outcomes.
    PLoS One. 2025;20:e0321269.
    PubMed         Abstract available
    
    
19. ROSA S, Pulido MA, Ruiz JJ, Cocucci TJ, et al
    Transmission matrix parameter estimation of COVID-19 evolution with age compartments using ensemble-based data assimilation.
    PLoS One. 2025;20:e0318426.
    PubMed         Abstract available
    
    
20. CHEN Q, Mat Sin NSB, Mohd Isa ANB, Chen D, et al
    Investigation on the association between college students' smartphone-related behaviors and sleep quality during COVID-19.
    PLoS One. 2025;20:e0321060.
    PubMed         Abstract available
    
    
21. LOHINIVA AL, Lehtinen JM, Arifulla D, Ollgren J, et al
    Factors influencing healthcare workers' compliance with personal protective equipment guidelines in long-term care during the COVID-19 pandemic-A theory-based mixed-methods study.
    PLoS One. 2025;20:e0321851.
    PubMed         Abstract available
    
    
22. SCHAEFER CM, Krause TM, Delclos GL, Greenberg RS, et al
    Risk of post-acute symptoms among adults: A comparison study of severe COVID-19, pneumonia, and influenza.
    PLoS One. 2025;20:e0322020.
    PubMed         Abstract available
    
    
23. WU R, He Y, Teng Z
    Energy price instability and energy efficiency: Korea's macroeconomic framework during the COVID-19 pandemic.
    PLoS One. 2025;20:e0321793.
    PubMed         Abstract available
    
    
24. GEBEYEHU DT, East L, Wark S, Islam MS, et al
    Food safety practices of individuals before and after the emergence of COVID-19: A pre- and post-comparative analysis.
    PLoS One. 2025;20:e0322235.
    PubMed         Abstract available
    
    
25. CARPALLO-PORCAR B, Jimenez-Sanchez C, Calvo S, Irun P, et al
    ARACOV-02. Specialized nutritional intervention and telerehabilitation in patients with long COVID: Protocol of a randomized controlled trial.
    PLoS One. 2025;20:e0321811.
    PubMed         Abstract available
    
    
26. OKMI M, Ang TF, Mohd Zaki MF, Ku CS, et al
    Mobile Phone Network Data in the COVID-19 era: A systematic review of applications, socioeconomic factors affecting compliance to non-pharmaceutical interventions, privacy implications, and post-pandemic economic recovery strategies.
    PLoS One. 2025;20:e0322520.
    PubMed         Abstract available
    
    
27. DENNIS A, Joseph J, Greenwell K, Miller S, et al
    A qualitative process evaluation of a nasal spray intervention to prevent respiratory tract infections.
    PLoS One. 2025;20:e0321314.
    PubMed         Abstract available
    
    
28. SHRESTHA S, Jha P, Shrestha L, Chaudhary LB, et al
    Trend of influenza before and during the COVID-19 pandemic in Nepal-A study from 2018 to 2022.
    PLoS One. 2025;20:e0299610.
    PubMed         Abstract available
    
    
29. FARUK MO, Siddik MAB, Chowdhury KUA, Bari N, et al
    Mental health of persons with disabilities during the COVID-19 pandemic in Bangladesh.
    PLoS One. 2025;20:e0322218.
    PubMed         Abstract available
    
    
30. HIRANBURANA N, Thippamom N, Avihingsanon A, Wacharapluesadee S, et al
    Differential immunogenicity in people living with HIV with varying CD4 levels after bivalent mRNA COVID-19 booster vaccination.
    PLoS One. 2025;20:e0317940.
    PubMed         Abstract available
    
    

    
    Proc Natl Acad Sci U S A

31. GRANULO A, Fuchs C, Bohm R
    Psychological reactance to system-level policies before and after their implementation.
    Proc Natl Acad Sci U S A. 2025;122:e2409907122.
    PubMed         Abstract available
    
    
32. CHI G, Abel GJ, Johnston D, Giraudy E, et al
    Measuring global migration flows using online data.
    Proc Natl Acad Sci U S A. 2025;122:e2409418122.
    PubMed         Abstract available
    
    

    
    Vaccine

33. SINGLETON KL, Post DJ, Augustine AD, Ison MG, et al
    Collaborative influenza vaccine innovation centers (CIVICs) program.
    Vaccine. 2025;54:127118.
    PubMed         Abstract available
    
    
34. ESSINK BJ, Vermeulen W, Andrade C, de Rooij R, et al
    Corrigendum to 'A randomised phase 2 immunogenicity and safety study of a MF59-adjuvanted quadrivalent subunit inactivated cell-derived influenza vaccine (aQIVc) in adults aged 50 years and older' Vaccine 51 (2025) 126791.
    Vaccine. 2025;56:127127.
    PubMed        
    
    
35. FATIMAH MNN, Thian BYZ, Wong CL, Ong HK, et al
    Chimeric virus-like particles of nodavirus displaying M2e of human and avian influenza A viruses as a potential dual-use vaccine: Inducing a broader immune response and protecting mice against viral infections.
    Vaccine. 2025;56:127165.
    PubMed         Abstract available
    
    
36. BUSTAMANTE Q, Sparkes D, Findlater L, Munro K, et al
    Understanding occupational and attitudinal factors influencing UK healthcare worker decisions for COVID-19 and influenza vaccination: A cross-sectional survey within SIREN.
    Vaccine. 2025;56:127160.
    PubMed         Abstract available

Modeling viral #shedding and #symptom #outcomes in #oseltamivir-treated experimental #influenza infection

Abstract

Influenza remains a global public health concern, and although the antiviral drug oseltamivir is widely used to treat infections, questions regarding its actual antiviral efficacy and clinical benefits remain. Here, we evaluated the effects of oseltamivir on viral shedding dynamics in the context of experimental influenza infection. We analyzed individual participant data, including viral load, time to symptom alleviation, and laboratory test measurements, obtained from three publicly available clinical trials involving experimental infections with influenza A and B viruses. We applied mathematical modeling and estimated parameters using a nonlinear mixed-effects model to capture viral infection dynamics. Our analysis revealed that, compared with placebo groups, the oseltamivir-treated groups tended to have lower values in terms of viral load area under the curve, duration of infection, peak viral titer, and time to peak; however, most of these differences were not significant; and no dose-dependent effects were observed. Moreover, there was no significant correlation between time to symptom alleviation and viral load. Some laboratory test parameters showed opposing correlations with symptom-related and viral load-related outcomes. These findings are consistent with distinct mechanisms underlying the symptom-alleviating effects of oseltamivir and its antiviral activity. Our findings suggest that the availability of individual-level data for public use is essential because it enables the evaluation of mechanisms in clinical trials and the development of more appropriate outcome measures.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.05.02.651873v1

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#Pigeons exhibit low susceptibility and poor #transmission capacity for #H5N1 clade 2.3.4.4b high pathogenicity avian #influenza virus

Abstract

The ongoing panzootic of H5N1 high pathogenicity avian influenza virus (HPAIV) has caused the deaths of over half a billion wild birds and poultry, and has led to spillover events in both wild and domestic mammals, alongside sporadic human infections. A key driver of this panzootic is the apparent high viral fitness across diverse avian species, which facilitates an increased interface between wild and domestic species. Columbiformes (pigeons and doves) are commonly found on poultry premises and are highly connected to humans in urban settlements, yet relatively little is known about their potential role in contemporary HPAIV disease ecology. Here we investigated the epidemiological role of pigeons (Columba livia) by determining their susceptibility using decreasing doses of clade 2.3.4.4b H5N1 HPAIV (genotype AB). We investigated infection outcomes and transmission potential between pigeons and to chickens for each dose. Following direct inoculation, pigeons did not develop clinical signs, and only those inoculated with the highest dose shed viral RNA or seroconverted to H5N1-AB, revealing a MID50 of 10^5 EID50. Even in the high dose group, only low-level shedding and environmental contamination was observed, and low-level viral RNA were present in the tissues of directly inoculated pigeons, with no distinct pathological lesions. Pigeons did not transmit the virus to naive pigeons or chickens placed in direct contact. Overall, these findings suggest that pigeons have a low susceptibility to clade 2.3.4.4b H5N1 HPAIV and are less likely to significantly contribute to disease ecology, incursions into poultry, or pose a significant zoonotic threat.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.05.02.651910v1

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#US CDC: #Results of #Influenza #Risk Assessment Tool {#IRAT, May 2 '25}

At a glance

-- The Influenza Risk Assessment Tool (IRAT) is a CDC evaluation tool developed with assistance from global animal and human health influenza experts.

-- The IRAT is used to assess the potential pandemic risk of influenza A viruses that are not currently circulating in people.

-- This latest IRAT assessed two recent clade 2.3.4.4b avian influenza A(H5N1) viruses: A/California/147/2024 and A/Washington/239/2024.

-- These viruses scored in the "moderate risk" category for potential emergence and public health impact, similar to previous assessments of earlier clade 2.3.4.4b avian influenza A(H5N1) viruses. These results validate the proactive, coordinated U.S. government response.

-- The IRAT does not assess the immediate risk to the public's health, which is unchanged and remains low, and it does not predict future pandemics.

Purpose

The IRAT uses expert opinion to evaluate the potential of a representative novel influenza A virus to gain the ability for person-to-person spread and the resulting potential public health impact if that were to happen, and it allows for comparison to other viruses evaluated in past IRAT reports. 

The IRAT does not assess the immediate risk to the public's health, and it does not predict future pandemics. 

The immediate risk to the public's health from clade 2.3.4.4b avian influenza A(H5N1) viruses is unchanged and is currently considered to be low. 

The current H5N1 bird flu situation continues to be mostly an animal health issue. 

Human infections with avian influenza A(H5N1) viruses are rare, and these viruses still are not well-adapted to spreading among people, as they do not currently have the ability to easily infect the human upper respiratory tract. 

Of the 70 cases in the United States from 2024-2025, 41 were associated with exposure to influenza A(H5N1)-infected cattle and 24 were associated with exposure to influenza A(H5N1)-infected poultry/birds. 

In addition, there were two cases with backyard poultry exposure and three cases with unknown exposure. 

Globally, most past human infections with avian influenza A(H5N1) viruses have occurred following close, unprotected contact with sick or dead birds.

This report summarizes the findings of an IRAT conducted on two viruses that caused recent human illnesses: 

-- A/California/147/2024 

and 

-- A/Washington/239/2024. 

The resulting score places both of these viruses, representative of two main groups of avian influenza A(H5N1) viruses currently circulating among animals in the United States, in the category of "moderate risk" for potential future emergence and public health impact. This is similar to previous assessments of earlier avian influenza A(H5N1) viruses. The scores for this IRAT were submitted on March 14, 2025.

During a public health response, the IRAT can be used to assess the appropriateness of the ongoing response efforts and whether additional actions are warranted based on the risk score. 

The results of this IRAT validate the proactive, coordinated U.S. government response. Assessing risk is an iterative process with new information being assimilated regularly and response activities adjusted as indicated.

Key findings

On May 2, 2025, CDC published a new IRAT assessment for two clade 2.3.4.4b avian influenza A(H5N1) viruses: A/California/147/2024 and A/Washington/239/2024. 

A/California/147/2024 is a B3.13 genotype virus, like the ones currently circulating in dairy cows in the United States and causing sporadic human infections, mostly among people who had exposure to H5N1 virus-infected or presumed infected dairy cattle. 

A/Washington/239/2024 is a D1.1 genotype virus, like those that are most commonly circulating in wild/migratory birds and also causing poultry outbreaks and sporadic human illnesses, mostly among people who had exposure to poultry confirmed to have influenza A(H5N1) virus infection. The genes of this virus are more closely related to what has been circulating most commonly in U.S. wild birds and poultry.

Previously, CDC assessed three other clade 2.3.4.4b avian influenza A(H5N1) viruses, including A/American wigeon/South Carolina/AH0195145/2021, A/mink/Spain/3691-8_22VIR10586-10/2022, and A/Texas/37/2024. All three previously assessed viruses had overall estimated IRAT scores in the moderate risk category range of 4.0 to 7.9.

This updated assessment includes new information, including information from additional human cases reported in the United States. 

This updated assessment indicates that these two viruses (A/California/147/2024 and A/Washington/239/2024) scored slightly lower in some risk elements and slightly higher in others compared with the previously assessed H5N1 clade 2.3.4.4b viruses. 

However, the mean-high and mean-low acceptable score ranges for these viruses overlap, indicating that these viruses remain similar, and their overall risk scores remain "moderate."

The average risk scores for the potential emergence of the A/California/147/2024 and A/Washington/239/2024 viruses were 5.59 and 5.21, respectively, placing them in the mid-low range of the moderate risk category.

The average risk scores for these two viruses to potentially impact public health was 5.91 and 6.00, respectively, placing them in the mid-range of the moderate risk category.

These scores reflect a decrease of at least 0.20 in the potential emergence question and a decrease of at least 0.09 in the potential public health impact question compared with the previous A/Texas/37/2024 virus evaluation from last year, but both questions on emergence and public health impact still fall into the moderate risk category.

Some variation was seen among subject matter expert (SME) point estimate scores across the risk elements, including Human Infections and Infections in Animals, where the scores ranged from moderate to high risk for the A/California/147/2024 virus, and Disease Severity and Pathogenesis, Global Distribution of Animal Influenza Viruses, and Human Infections for the A/Washington/239/2024 virus. This indicates some uncertainty in interpretation and confidence of the available data.

Sensitivity analyses using the lowest and highest scores for these four risk elements resulted in adjusted ranges for the overall emergence risk and the potential impact risk that continued to place this virus in the mid-range of the moderate risk category. This indicates that the categorization of HPAI A(H5N1) clade 2.3.4.4b virus, including A/California/147/2024 and A/Washington/239/2024, as moderate risk was unchanged by the range of scores within the risk elements exhibiting variation.

The full report is available at Virus Descriptions and Report Summaries.

Background

Input on IRAT assessments is provided by a diverse group of U.S. government animal and human health influenza experts. More information about the IRAT, including a description of its methodology and definitions for its risk elements and categories, is available at Influenza Risk Assessment Tool (IRAT). The IRAT is updated when new zoonotic or novel influenza A viruses with pandemic potential emerge or undergo a change in characteristics that prompts the need for a new assessment.

Summary of U.S. Human Cases of H5 Bird Flu

In the United States since April 2024, 70 human illnesses with H5 bird flu have been reported in 13 states. One additional human case of H5N1 bird flu was reported in the United States in April 2022 in a farm worker who experienced fatigue without any other symptoms and while depopulating poultry at a poultry farm with confirmed avian influenza A(H5N1) virus.

Summary of U.S. human cases associated with dairy cattle exposure

The first human case in the United States associated with the outbreaks of A(H5N1) virus among dairy cattle was reported on April 1, 2024, by the State of Texas. As of April 2024, 41 human cases of H5 bird flu have been associated with the ongoing multi-state outbreak of A(H5N1) in dairy cattle, with 36 cases occurring in California, two cases in Michigan, and one case each reported in Colorado, Nevada and Texas. All infections occurred in dairy workers who had direct exposure to cattle presumed to be infected with A(H5N1) virus. Infections associated with U.S. dairy cattle to date have involved mild respiratory symptoms or conjunctivitis. No patients have been hospitalized.

Summary of U.S. human cases associated with poultry or backyard flock exposure

Twenty-four human cases of H5 bird flu have been detected in farm workers who were involved in the depopulation of poultry at a poultry facility experiencing an outbreak of HPAI A(H5N1) virus, and two cases involved exposures to backyard flocks in Louisiana and Wyoming. Eleven of the 24 cases in farm workers were reported in Washington state, nine in Colorado, and one each in Iowa, Ohio, Oregon, and Wyoming. Most of these workers who tested positive reported mild illness, such as redness/watery eyes and respiratory symptoms. However, one case in Ohio was severe and required hospitalization; the patient subsequently recovered. In addition, the two cases exposed to backyard birds were severe, required hospitalization, and one died.

Summary of U.S. human cases with no known animal exposure

The exposure source is unknown for three cases, two cases in children in California and one adult case in Missouri.

(...)

Source: US Centers for Disease Control and Prevention, https://www.cdc.gov/pandemic-flu/php/monitoring/irat-virus-summaries.html

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#USA, Monitoring for Avian #Influenza A(#H5) Virus In #Wastewater (as of May 2 '25)

{Excerpt}

Time Period: April 20, 2025 - April 26, 2025

- H5 Detection: 5 sites (1.2%)

- No Detection: 402 sites (98.8%)

- No samples in last week: 91 sites

(...)

Source: US Centers for Disease Control and Prevention, https://www.cdc.gov/bird-flu/h5-monitoring/index.html

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#H5 #influenza virus #mRNA-lipid nanoparticle (LNP) #vaccination elicits adaptive immune responses in Holstein #calves

Abstract

Highly pathogenic avian influenza (HPAI) clade 2.3.4.4b H5N1 is circulating widely in lactating cows in the United States. Due to the critical need for intervention strategies for this outbreak, we evaluated antibody and cellular immune responses of a clade 2.3.4.4b H5 mRNA-LNP vaccine in calves. We found that the H5 mRNA-LNP vaccine induced a robust antibody and CD8+ T cellular-mediated immune response and conferred protection against clade 2.3.4.4b H5N1 infection.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.05.01.651548v1

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#Ecology and #environment predict spatially stratified #risk of #H5 highly pathogenic avian #influenza clade 2.3.4.4b in wild #birds across #Europe

Abstract

Highly pathogenic avian influenza (HPAI) represents a threat to animal and human health, with the ongoing H5N1 outbreak within the H5 2.3.4.4b clade being the largest on record. However, it remains unclear what factors have contributed to its intercontinental spread. We use Bayesian additive regression trees, a machine learning method designed for probabilistic modelling of complex nonlinear phenomena, to construct species distribution models (SDMs) for HPAI clade 2.3.4.4b presence. We identify factors driving geospatial patterns of infection and project risk distributions across Europe. Our models are time-stratified to capture both seasonal changes in risk and shifts in epidemiology associated with the succession of H5N6/H5N8 by H5N1 within the clade. While previous studies aimed to model HPAI presence from physical geography, we explicitly consider wild bird ecology by including estimates of bird species richness, abundance of specific taxa, and "abundance indices" describing total abundance of birds with high-risk behavioural traits. Our projections of HPAI clade 2.3.4.4b indicate a shift in persistent, year-round risk towards cold, low-lying regions of northwest Europe associated with H5N1. Methodologically, we demonstrate that while most variation in risk can be explained by climate and physical geography, adding host ecology is a valuable refinement to SDMs of HPAI.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.07.17.603912v2

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