ETIDIOH - NEW

  ABSTRACT Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a bat-originated virus causing severe diseases in piglets . Since the 2016 outbreak , diverse SADS-related CoVs (SADSr-CoVs) have been detected in Rhinolophus bats in China and Southeast Asia , but their potential interspecies infection and pathogenicity remain unknown. Herein, we sequenced the spike (S) genes of bat SADSr-CoVs and classified them into four genotypes . We constructed an infectious SADS-CoV cDNA clone (rSADS-CoV) and nine recombinant viruses by replacing the SADS-CoV S gene with that of bat SADSr-CoVs. Recombinant SADSr-CoVs could replicate efficiently in respiratory and intestinal cell lines and human- and swine-derived organoids and caused varying tissue damage and mortality in suckling mice. These viruses can be classified into at least five serotypes based on cross-neutralization assays . Our findings highlight the potential risk of interspecies infection and provide important information for fut...

  Abstract SARS-CoV-2 Spike - the sole neutralization target, is highly resilient to the immune pressure driving genetic evolution . While potency and breadth of neutralization are widely studied, the incomplete neutralization - the mechanism of resistance without needing genetic change - remains unexplored . Several monoclonal antibodies , although potent, showed incomplete neutralization of genetically homogeneous pseudovirus suggesting the existence of distinct spike conformations . The residual infectivity at high antibody concentration indicates a viral fraction with intrinsic resistance to the antibody. Although the published studies on spike glycosylation, structure, and conformations provide evidence of spike heterogeneity the precise mechanism for the incomplete neutralization has not been established. In this study, we devise a method to separate the un-neutralized virion population , called as persistent fraction of infectivity (PF), and characterize the viral spike prot...

  ABSTRACT With the SARS-CoV-2 Omicron XBB.1.9 subvariants circulating worldwide, two XBB.1.9 variants, EG.5.1 and HK.3 , spread rapidly and became dominant in mid-2023. However, the spike features, pathogenicity, and transmissibility of HK.3 are largely unknown. Here, we performed multiscale investigations to reveal the virological features of XBB.1.9 subvariants , including the newly emerging HK.3 . HK.3 revealed high replication efficiency and enhanced TMPRSS2 utilization in vitro. The HK.3 spike exhibited enhanced processing, although its infectivity, fusogenicity, and human ACE2 (hACE2) binding affinity were comparable to those of the EG.5 and XBB.1 spikes. All XBB.1.9.1, EG.5.1, and HK.3 strains demonstrated efficient transmission in hamsters , although XBB.1.9.1 exhibited stronger fitness in the upper airways . XBB.1.9.1, EG.5.1, and HK.3 exhibited greater pathogenicity than BA.2 in H11-K18-hACE2 hamsters. Our studies provide insights into the newly emerging pathogens EG.5.1...

  Significance Annual influenza epidemics in the United States cause hundreds of thousands of hospitalizations . Quantifying vaccine impact is vital, yet many analyses overlook vaccines’ dual benefits : directly protecting recipients and indirectly protecting their contacts . Using a mathematical model that accounts for both effects, we estimate that vaccination prevented about 70,000 hospitalizations during the 2022–2023 season , with another 19,000 potentially avoidable if coverage met the 70% national target. Despite uncertainty in vaccine effectiveness against infection, our findings suggest that vaccinating younger adults offers substantial indirect protection for older adults. Tailoring annual vaccination campaigns by age group and state could further strengthen their public health impact. Abstract During the COVID-19 pandemic early years, infection prevention measures suppressed transmission of seasonal influenza and other respiratory viruses . The early onset and moderate s...

  Abstract Background Plague, a zoonosis caused by Yersinia pestis, is endemic in Madagascar but knowledge on the epidemiological situation in the northern focus remains unclear . The aim of this study was to investigate the circulation of Y. pestis in terrestrial small mammals in north eastern Madagascar, where suspected plague outbreaks have been reported. Methods Sampling of terrestrial small mammals and their fleas was carried out in 22 trapping sites within 9 localities of the two sectors (1 and 3) of Makira Natural Park (MNP) and surroundings, from 2020 to 2022. Yersinia pestis was investigated in terrestrial small mammal spleen samples and their fleas using bacteriological, serological and molecular methods. Results A total of 614 terrestrial small mammals composed of eight species and 1,754 individual fleas were collected following 4,880 trap-nights. The black rat (Rattus rattus) represented the majority (87.8%) of the small mammal species caught. Flea infestation rate was ...

  Summary Background First discovered in 1999 in Malaysia, Nipah virus (NiV) causes yearly outbreaks throughout south and southeast Asia with associated mortality rates of 40–75 %. Due to the structural and sequence similarities between the NiV and Hendra virus (HeV) attachment G glycoproteins , and the extensive extant evidence of the ability of a recombinant soluble glycoprotein G (HeV-sG) to provide heterologous cross-protective immunity when used as vaccine (HeV-sG-V), this study aimed to evaluate HeV-sG-V for safety, tolerability, and immunogenicity against NiV. Methods We conducted a phase 1, single-centre, randomised, observer-blind, placebo-controlled study . Eligible participants were aged 18–49 years, healthy, and not pregnant; participants were ineligible if they were immunocompromised, had received blood products within 6 months of enrolment, had potential exposure to NiV or HeV, or had known allergies to components of the vaccine. Participants were randomly assigned in...

  Int J Infect Dis SILVA CAC, Bomfim AP, Medeiros JD, Silva JJ, et al Nasal Microbiota and Clinical Features in Acute Flu-Like Illness: COVID-19 Status and Long COVID Follow-Up. Int J Infect Dis. 2025 Nov 11:108196. doi: 10.1016/j.ijid.2025.108196. PubMed           Abstract available SONG J, Jeong S, Chun AY, Jung J, et al Incidence of Respiratory Infections after the COVID-19 Pandemic (2023-2024) and Its Association of Vaccination Among Entire Populations in Korea. Int J Infect Dis. 2025 Nov 7:108194. doi: 10.1016/j.ijid.2025.108194. PubMed           Abstract available VERGORI A, Matusali G, Lepri AC, Cimini E, et al Supporting equitable booster strategies: one-year real-world immunogenicity data in people with HIV (PWH) receiving different variant-adapted COVID-19 vaccines. Int J Infect Dis. 2025 Nov 7:108189. doi: 10.1016/j.ijid.2025.108189. PubMed           Ab...

  Arch Virol WANG P, Fu J, Wu H, Zhu L, et al Amino acid substitutions associated with adaptation of novel H10N3 and H10N5 avian influenza viruses to mice. Arch Virol. 2025;170:242. PubMed          Drug Saf WONG J, Donegan K, Harrison K, Jan T, et al Implementation and Results of Active Vaccine Safety Monitoring During the COVID-19 Pandemic in the UK: A Regulatory Perspective. Drug Saf. 2025;48:1365-1385. PubMed           Abstract available VAN HOLLE L Observed Versus Expected Analysis-How Does It Fit in the Pharmacovigilance Toolkit? Drug Saf. 2025;48:1325-1330. PubMed           Abstract available Drugs LEE A Onradivir: First Approval. Drugs. 2025;85:1609-1612. PubMed           Abstract available J Clin Microbiol HOGAN CA, Le AT, Khan A, Su LD, et al Comprehensive metabolomics combined with machine learning for the identificatio...

  Abstract We describe the clinical symptoms and epidemiologic characteristics of a patient infected with avian influenza A(H10N3) virus in Guangxi Province , China, in December 2024. Whole-genome sequencing showed that the virus was highly homologous to a virus from Yunnan Province . H10 subtype viruses should be monitored for potential zoonotic or reassortant events. Source: US Centers for Disease Control and Prevention,  https://wwwnc.cdc.gov/eid/article/31/11/25-0847_article ____

  Abstract H7 high-pathogenicity avian influenza (HPAI) virus outbreaks can cause high rates of morbidity and mortality in poultry flocks , leading to devastating impacts on poultry industries. In December 2024 , an HPAI virus was detected on a poultry farm in New Zealand , being the first time a case of HPAI was reported in the country. Whole-genome sequencing, subtyping, phylogenetic, and mutation analyses were performed to characterize the virus. Results indicated a novel high-pathogenicity H7N6 avian influenza virus arose through a reassortment event between endemic low-pathogenicity H4N6 and H7 viruses, followed by two mutations at the H7 gene cleavage site . Mutation analysis suggests the novel H7N6 virus exhibits increased risk of host specificity shift , but further work is required to fully understand the functional impacts of the detected mutational events. In this instance, a timely biosecurity response was effective in eliminating the virus and preventing its transmissi...

  {Excerpt} The constant emergence of novel SARS-CoV-2 variants has driven the COVID-19 pandemic and sustains the current endemic . Saltation variants , such as BA.2.86 ,1 encode highly mutated spike (S) proteins that efficiently evade neutralising antibodies . In November, 2024, a potential saltation variant, BA.3.2 , was detected in South Africa but its spread remained uncertain. Early studies on BA.3.2 did not include comparisons among its subvariants or with dominant variants NB.1.8.1 and XFG.2 ,3 Moreover, the effect of the often overlooked S protein insertion of Ala-Ser-Asp-Thr at position 214 remained unexamined. In this Correspondence, we provide an epidemiological and virological update on BA.3.2, with the use of BA.3 (parental lineage) and NB.1.8.1 and XFG (currently prevalent) as references. (...) Source: The Lancet Infectious Diseases,  https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(25)00658-9/fulltext?rss=yes ____

  Highlights •  Human antibody HB420 cross-reacts with neuraminidases from H3N2 and H5N1 •  HB420 engages the neuraminidase active site via a single Asp residue •  Germline HB420 is N2 specific but gains reactivity to N1 through somatic mutation •  HB420 provides in vivo protection against both H3N2 and H5N1 Summary The ongoing spread of highly pathogenic avian influenza H5N1 clade 2.3.4.4b virus in animals and its occasional spillover to humans have raised concerns about a potential H5N1 pandemic . Although recent studies have shown that pre-existing human antibodies can recognize H5N1 neuraminidase , the molecular basis of how this cross-reactivity develops remains poorly understood. In this study, we used a phage display antibody library derived from 245 healthy donors to isolate an antibody, HB420, that cross-reacts with neuraminidases of human H3N2 and avian H5N1 clade 2.3.4.4b viruses and confers protection in vivo. Cryogenic electron microscopy analysis r...

  Abstract Most emerging human infectious diseases are derived from animals , and monitoring such zoonoses is imperative to help prevent future outbreaks . In this Forum , we discuss the knowledge gaps in our current understanding of viral ecology, global disparities in virus discovery , and the applications of artificial intelligence in infectious disease monitoring. Source: Cell Host & Microbe,  https://www.cell.com/cell-host-microbe/abstract/S1931-3128(25)00429-9?rss=yes ____

  Abstract Influenza viruses cause hundreds of thousands of infections globally every year. In the past century, seasonal influenza viruses have included H1N1, H2N2 or H3N2 strains . H2N2 influenza viruses circulated in the human population between 1957-1968 . Previously, our group demonstrated a lack of H2N2 influenza virus immunity in individuals born after 1968 , as well as the effectiveness of hemagglutinin (HA) based vaccines for multiple influenza virus subtypes. In this study, H2 antigenic maps and radial graphs were generated using previously published data from H2 HA vaccinations of ferrets and seasonal influenza vaccinations of humans . The antigenic maps revealed a stark difference in clustering of HA antigens between the ferrets and humans, and the radial graphs showed specific antigen recognition varies greatly between different influenza preimmune ferrets . These maps also revealed the significant impact that different pre-existing immunities have on antigenic recogni...

  Abstract The spread of H5N1 clade 2.3.4.4b in dairy herds raises concerns about zoonotic transmission due to its high viral load in milk , a key contact point between livestock and humans . H5N1 clade 2.3.4.4b exhibits tropism for the mammary gland , with milk from infected animals containing high levels of infectious virus , posing potential risks to offspring via breastfeeding . Using a lactating ferret model , we demonstrate that mammary gland infection with bovine H5N1 transmits the virus to suckling kits , resulting in neonatal mortality . Viral RNA levels increased in milk and remained high in mammary tissue, with infected kits exhibiting elevated viral RNA in the oral and nasal cavities and feces . Additionally, we detected the H5N1 receptor, α2,3 sialic acid , in ferret and human mammary tissue . These data demonstrate that H5N1 clade 2.3.4.4b infection in lactating dams leads to mastitis-related disease and transmits to suckling pups, resulting in mortality among neonate...

  Abstract The highly pathogenic H5N1 avian influenza A virus (IAV) clade 2.3.4.4b has spread globally and spilled over into multiple mammalian species , raising concerns about its pandemic potential . In late 2022, clade 2.3.4.4b viruses devastated seabird and marine mammal populations along the Pacific coast of South America . Here, we report the first evidence of H5 IAV infections in wild bats globally, focusing on common vampire bats (Desmodus rotundus) in coastal areas of Peru . Longitudinal serological screening , stable isotope analysis and metabarcoding revealed repeated exposures to H5 IAVs in vampire bats which feed on coastal wildlife species heavily impacted by the 2.3.4.4b epizootic, but no evidence of infection in populations without access to marine prey. We further report bat gene flow between IAV-exposed and IAV-naive populations , and IAV infections in a vampire bat colony that fed on both marine and terrestrial livestock prey, providing insights into how future I...

  Summary -- What is already known about this topic? - A total of 117 H9N2 cases of human infection of Chinese origin had been reported to the World Health Organization (WHO) by May 9, 2025, with 22 of them originating in Hunan Province. -- What is added by this report? - This article reported on the investigation of three new H9N2 avian influenza virus (AIV) infections detected in Changsha, Hunan Province , in April 2025. No epidemiological link was found among them. Exposure to live poultry was identified as the primary risk factor for infection. Sequence analysis of the three H9N2 AIVs showed a similarity of 99.71%–99.82% between hemagglutinin (HA), and the homology of the neuraminidase (NA) genes was 98.41%–99.83%. Although the tests showed that the HA had enhanced binding ability to upper respiratory tract cells’ receptors , no evidence of sustained human-to-human transmission has been found so far. -- What are the implications for public health practice? - This study indicate...

  Summary -- What is already known about this topic? - The H3N8 avian influenza virus (AIV) demonstrates considerable capacity for interspecies transmission and has been documented in multiple mammalian hosts , including equine and canine species. During 2022–2023, three laboratory-confirmed human infections with H3N8 were reported in China, heightening public health concerns about the zoonotic spillover potential of H3 subtype AIVs. -- What is added by this report? - This study reports the isolation of a genetically reassorted, low-pathogenicity H3N8 avian influenza virus (AIV) from an islet in Niukouyu Wetland Park, Beijing Municipality — the first detection of this viral strain in a wild environment within the city. Throat swabs collected from park staff tested negative for influenza viruses. Phylogenetic analysis demonstrated that the viral hemagglutinin gene originated from the Eurasian lineage, while the neuraminidase gene was derived from the North American lineage . Althoug...

  Abstract Influenza pandemics arise when novel influenza virus subtypes emerge in populations with little or no pre-existing immunity . The recent expansion of H5N1 virus circulation in mammals — including documented spread in cattle and sporadic human infections — coupled with the emergence of mutations associated with enhanced pandemic potential , underscores the persistent threat of novel influenza strains. Pandemic preparedness critically depends on developing effective vaccines capable of providing broad protection across diverse viral strains. While vaccination remains the most effective strategy for preventing influenza and its complications, pandemic vaccine development faces substantial challenges . These include the rapid mutation rates characteristic of influenza viruses, driven by error-prone RNA replication, broad host range, environmental selection pressures, and frequent genetic recombination. Such factors complicate predictions of which strain will trigger the next...

  Authors: Freja CM Kirsebom{1}, Catherine Thompson{2}, Tiina Talts{2}, Beatrix Kele{2}, Heather J Whitaker{3}, Nurin Abdul Aziz{1}, Christopher Rawlinson{1}, Rebecca E Green{1}, Catherine Quinot{1}, Nicholas Gardner{1}, Elizabeth Waller{1}, Alex Allen{1}, Conall H Watson{1,4}, Suzanna LR McDonald{1}, Maria Zambon{2}, Richard Pebody{4,5}, Mary Ramsay{6,7}, Katja Hoschler{2}, Anika Singanayagam{*2,4}, Jamie Lopez Bernal{*1,4}  {*} Joint last authors  {1} Immunisation and Vaccine-preventable Diseases Division, UK Health Security Agency, Colindale, London  {2} Respiratory Virus Unit (RVU), UK Health Security Agency, Colindale, London  {3} Modelling Division, UK Health Security Agency, Colindale, London  {4} NIHR Health Protection Research Unit in Respiratory Infections, Imperial College London, United Kingdom  {5} Epidemic and Emerging Infections Directorate, UK Health Security Agency, Colindale, London  {6} Public Health Programmes Directorate, UK H...