ETIDIOH - NEW

  Abstract Background Oropouche virus (OROV) is an emerging arbovirus primarily transmitted by biting midges and is increasingly recognized as a public health threat in Central and South America . With over 11,000 confirmed cases reported in 2024, a ten-fold increase from the previous year, its transmission dynamics and true burden remain poorly understood due to diagnostic challenges and fragmented surveillance systems. Objective This systematic review and meta-analysis (SRMA) synthesizes OROV prevalence data in humans and summarizes the available data for vectors and animal hosts sampled between 2000 and 2024 to provide updated estimates and identify key surveillance gaps. Methods We systematically searched Web of Science, PubMed, Embase, Medline, and LILACS for OROV seroprevalence and viral prevalence studies in human, insect, and animal populations, published up to September 12, 2024. The review protocol was registered with PROSPERO (CRD42024551000). Studies were extracted in d...

  Abstract Highly pathogenic avian influenza (HPAI) A(H5N1) clade 2.3.4.4b has recently emerged as a major threat to wildlife , agriculture, and public health due to its expanding host range and the increasing frequency of spillover into mammals . In July–August 2023, the mass death of over 3500 northern fur seals (Callorhinus ursinus) and at least one Steller sea lion (Eumetopias jubatus) was recorded on Tyuleniy Island in the Sea of Okhotsk, Russia. Two HPAI A( H5N1 ) viruses were isolated from fur seal carcasses and designated A/Northern_fur_seal/Russia_Tyuleniy/74/2023 and A/Northern_fur_seal/Russia_Tyuleniy/75/2023. Both viruses exhibited high pathogenicity in chickens (IVPI 2.7–3.0) and mice (MLD50 1.9–2.5 log10EID50/mL), with distinct differences in disease progression, histopathology, and organ tropism . Experimental infection of mice revealed that strain A/74/2023 induced more severe pulmonary and neurological lesions than A/75/2023. Whole-genome sequencing and phylogeneti...

  Abstract   SARS-CoV-2 is a major global public health burden associated with significant morbidity, mortality, and complications , including respiratory, cardiovascular, neurological , and digestive disorders. COVID-19 may induce venous and arterial thromboembolic complications , including deep vein thrombosis , myocardial infarction and cerebral infarction . Simultaneous myocardial and cerebral infarction, termed cardio-cerebral infarction , is exceedingly rare. There is only limited case of concurrent cardio-cerebral infarction in patients with COVID-19 . Although there is no standard treatment for the condition, antiplatelet and anticoagulation agents should be used. We emphasize the catastrophic coexistence of concurrent cardio-cerebral infarction in a patient co-infected with SARS-CoV-2 and influenza A. We described a 75-year-old woman was admitted for SARS-CoV-2 and influenza A coinfection . She received anti-viral agent treatment for the virus infection. The patient p...

  Overall Risk statement -- This RRA aims to assess the overall public health risk at the global level posed by the chikungunya virus (CHIKV) transmission during 2025, considering the criteria of potential risk for human health , the risk of geographical spread , and the risk of insufficient control capacities with available resources, and the implications for the 2026 transmission season .  -- Chikungunya virus (CHIKV) poses a significant and growing global health risk due to large and widespread regional outbreaks in recent years, climate-driven mosquito expansion , lack of specific treatment , and increasing international travel.  -- While mortality remains relatively low , the CHIKV infection can cause prolonged arthritis with disability as well as  severe illness in some patients.  -- From 1 January to 10 December 2025, 502 264 CHIKV disease cases including  208 335 confirmed cases, and 186 CHIKV deaths , were reported globally.  -- While certain ...

  Public domain. Source:  Link:  https://www.wikiart.org/en/jan-van-eyck/madonna-at-the-fountain-1439 ____

  Abstract Mexico has experienced recurrent viral epidemics of substantial intensity, including hyperendemic dengue, COVID-19, and recent reports of avian influenza A (H5N1) infections in birds , which pose an ongoing risk of zoonotic transmission . Mexico was also the location for the earliest detection of the pdmH1N1 virus during the 2009 influenza A pandemic. Under a One Health framework , markets represent a unique opportunity for low-cost virus monitoring at the human-animal interface . Under the hypothesis that these represent sentinel sites for an early virus detection , we implemented a pilot surveillance program at the central market of Merida city, Yucatan , Mexico, considered a regional hotspot for multiple and recent viral outbreaks . Longitudinal sampling was carried out over 11 months at 1-to-6-week intervals from April 2022 to February 2023 . We used multi-type surveillance in mosquitoes, live poultry, and wastewater . All samples were screened using RT-qPCR . Positi...

Von Col André Kritzinger, CC BY-SA 3.0,  https://commons.wikimedia.org/w/index.php?curid=11506789 Source:  Link:  https://de.wikipedia.org/wiki/Spoornet-Klasse_14E ____

Par Daniel Wipf — Travail personnel, CC BY-SA 4.0,  https://commons.wikimedia.org/w/index.php?curid=59022313 Source:  Link:  https://fr.wikipedia.org/wiki/EC_250_%C2%AB_Giruno_%C2%BB ____

  Abstract Human (avian) influenza A viruses, especially highly pathogenic avian influenza (HPAI) viruses, pose a significant public health threat , and a multivalent vaccine is the primary prophylactic measure to control these viruses. To establish such a vaccine, we generated two multivalent vesicular stomatitis virus (VSV)-based vaccine candidates (V-EtM2e/H505 and V-EtM2e/H522) and characterized their ability to induce protective immune responses. Our results revealed that vaccine immunization in mice induced high humoral immune responses against both the HPAI hemagglutinin (HA) protein and the ectodomain of M2 (M2e) protein . Intriguingly, vaccine-immunized mouse sera exhibited highly efficient neutralizing activity against the corresponding H5 pseudovirus and mediated potent and broad antibody-dependent cellular cytotoxicity (ADCC) activity against M2e derived from human and avian influenza H5, H1, H3, and H7 viruses . Furthermore, both intranasal and intramuscular immunizati...

  Abstract SARS-CoV-2 immunity and innate immune training may influence influenza vaccine immunogenicity . We investigated this in India . Adult volunteers with hybrid SARS-CoV-2 immunity were administered FluarixTM Tetra (GlaxoSmithKlein) 2022/2023 NH Vaccine in 2022. Significant induction of hemagglutinin inhibition-specific antibodies and polyfunctional central memory CD4+ T-cells (TCM) were observed 1-week post-vaccination with variable induction of CD8+T-cell and innate effectors. Vaccination also expanded Flu-specific regulatory T-cells (Treg), which negatively correlated with CD4 responses , highlighting vaccine immunogenicity may be subject to Treg dampening . FluarixTM did not boost SARS-CoV-2 immunity . However, SARS-CoV-2 -specific T-cell responses correlated positively with vaccine-induced T-cell responses. We evaluated trained immunity post-COVID-19 as a potential regulatory mechanism linking SARS-CoV-2 and heterologous vaccine immunogenicity . We observed, elevated fr...

  Abstract The global spread of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b viruses has recently extended to include diverse mammalian species , raising new concerns about pandemic risk . In 2023, this clade was first detected in Russian marine mammals during a mass mortality event among northern fur seals in the Far East . Genetic analyses revealed the causative viruses to belong to genotype A3 of European origin , which is known to have circulated in wild birds across the Far East since 2022. Notably, these isolates harbor the mammalian-adaptive substitutions PB2-K482R and NP-N319K—mutations previously linked to enhanced virulence in non-H5 avian influenza viruses , but whose impact on A(H5N1) clade 2.3.4.4b viruses remained to be characterized. The heightened virulence of A3 genotype viruses is confirmed by data obtained via a mouse model . However, despite these adaptive changes, ferret transmission models showed no evidence of airborne transmission of the fur seal...

  Abstract We investigated macrolide resistance and P1 genotypes of Mycoplasma pneumoniae during the 2024–2025 outbreak in Hamilton, Ontario, Canada . Macrolide resistance remained stable at ≈10%–20%, but significant shifts in P1 genotype distribution and resistance rates in P1 types occurred, indicating notable changes in M. pneumoniae molecular epidemiology in Ontario since 2011–2012. Source:  Link:  https://wwwnc.cdc.gov/eid/article/31/12/25-0872_article ____

  Abstract Up-to-date estimates of COVID-19 vaccine effectiveness (VE) are needed to inform COVID-19 vaccination strategies and recommendations . This target trial emulation study aimed to estimate the long-term vaccine effectiveness (VE) of the 2024-2025 COVID-19 vaccines targeting the KP.2 Omicron variant within the Veterans Health Administration . The study population (90.9% male, mean age 70.7 years) included 538,631 pairs of vaccinated (i.e., received the KP.2 COVID-19 vaccine) and matched unvaccinated (i.e., did not receive the KP.2 COVID-19 vaccine) persons enrolled from August 2024 to January 2025. Over a mean follow-up of 172 days (range 97-232) extending to April 12, 2025, VE was low against laboratory-diagnosed SARS-CoV-2 infection ( 16.60%, 95% confidence interval [CI], 11.92-21.44), SARS-CoV-2-associated emergency department/urgent care (ED/UC) visit ( 21.05%, 95% CI, 14.22-27.21), SARS-CoV-2-associated hospitalization ( 19.53%, 95% CI 6.56-30.10) and much higher again...

  Situation at a glance Since the beginning of 2025 and as of 21 December 2025, a total of 19 cases of Middle East respiratory syndrome coronavirus (MERS- CoV), including four deaths have been reported to WHO globally.  Of the 19 cases, 17 were reported by the Kingdom of Saudi Arabia (KSA), and two were reported from France .  Between 4 June and 21 December 2025, the Ministry of Health (MoH) of KSA reported a total of seven cases of MERS-CoV infection, including two deaths .  In addition , at the beginning of December 2025, the National IHR Focal Point (IHR NFP) for France also reported two MERS-CoV travel – associated cases ; involving individuals with recent travel to countries in the Arabian Peninsula.  The notification of these latest cases does not change the overall risk assessment , which remains moderate at both the global and regional levels .  These cases show that the virus continues to pose a threat in countries where it is circulating in dromed...

  {Eurasian Teal} {Eurasian Wigeon} {Mute Swan} ___ This is a new event opened to report outbreaks for which the N subtype could not be determined due to insufficient diagnostic material; in these cases, only the presence of H5 can be confirmed. Three Common Teals (Friuli Venezia Giulia, Lombardy) , two Eurasian Wigeons (Friuli Venezia Giulia), one Mute Swan (Lombardy).  Source:  Link:  https://wahis.woah.org/#/in-review/7144 ____

  The Official Veterinary Service (OVS) of the state of Mato Grosso received a notification of a suspected case influenza A viruses of high pathogenicity in domestic birds from a multi-species backyard , on December 20, 2025. Official Laboratory (LFDA-SP) analysis confirmed the presence of the H5N1 virus, clade 2.3.4.4b. The premises have been placed under quarantine. Birds will be culled, and carcasses, products, and any potentially contaminated materials will be destroyed. The OVS is currently conducting an epidemiological investigation in the surrounding area. Source:  Link:  https://wahis.woah.org/#/in-review/7147 ____

  Abstract Since 2021, highly pathogenic avian influenza viruses (HPAIV) belonging to H5N1 clade 2.3.4.4b have caused high mortality in North American wild birds and poultry . In 2025 , a new D1.1 genotype caused two human deaths and host-switched to dairy cattle . However, the evolutionary origins and dynamics of D1.1 have not been fully characterized. Here, our phylogenetic analysis of 17,516 H5N1 genome sequences uncovers how D1.1 introduced a major shift in the antigenic diversity and ecology of the H5N1 epizootic in North America. D1.1 is the first major H5N1 genotype to (a) emerge in the Pacific flyway and spread west-to-east faster than any prior genotype; (b) antigenically shift via reassortment with the North American N1 segment, displacing the previously fixed Eurasian N1 ; and (c) transmit to a broader range of host species than any H5N1 genotype to date, introducing mammalian adaptations . Competing Interest Statement The authors have declared no competing interest. Fun...

  ABSTRACT The 2009 pandemic H1N1 (pH1N1) influenza A virus (IAV) is a reassortant virus with two polymerase components, PA and PB2, originating from avian IAV . Avian IAV polymerase does not function efficiently in mammalian cells without host-adaptive mutations . The mechanism by which pH1N1 replicates in human hosts is not fully elucidated , as pH1N1 does not contain the host-adaptive PB2 E627K mutation required for species-specific interaction with ANP32 , which facilitates replicase (polymerase oligomer) formation. Our previous research revealed that mutations in PA played a key role in mammalian host adaptation of pH1N1. These mutations were found in two separate domains of PA, the C-terminal (CTD) and N-terminal domains (NTD). We reported that the NTD mutations increase the expression of NP through enhanced association of GRSF1 with the mRNA transcripts. However, the role of CTD mutations, which are located at the interface of the polymerase oligomers , has not been elucidat...

  Abstract Influenza D virus (IDV) is prevalent in cattle in China , and a risk for spillover to other species exists. We detected IDV antibodies in 6/315 of black donkeys in northern China , suggesting cattle-to-donkey transmission and demonstrating the expanding host range of IDV and the need for reassessment of cross-species transmission risks. Source:  Link:  https://wwwnc.cdc.gov/eid/article/31/12/25-0666_article ____

  Abstract Poultry workers in Washington, USA, were infected with highly pathogenic avian influenza A(H5N1) virus and recovered. The viruses were clade 2.3.4.4b genotype D1.1, closely related to viruses causing poultry outbreaks . Continued surveillance and testing for influenza A(H5) clade 2.3.4.4b viruses remain essential for risk assessment and pandemic preparedness of zoonotic influenza viruses. Source:  Link:  https://wwwnc.cdc.gov/eid/article/31/12/25-1118_article ____