ETIDIOH - NEW

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 develo...

Abstract Highly Pathogenic Avian Influenza (HPAI) is a prominent candidate for a future human pandemic arising from a zoonotic spillover event . Its best-known strain is H5N1 , with South- or South-East Asia a likely location for an initial outbreak. Such an outbreak would be initiated through a primary event of bird-to-human infection, followed by sustained human-to-human transmission . Early interventions would require the extraction, integration and interpretation of epidemiological information from the limited and noisy case data available at outbreak onset. We studied the implications of a potential zoonotic spillover of H5N1 influenza into humans. Our simulations used BharatSim , an agent-based model framework designed primarily for the population of India , but which can be tuned easily for others. We considered a synthetic population representing farm-workers (primary contacts) in a farm with infected birds. These primary contacts transfer infections to secondary (household) co...

Abstract Zoonotic diseases have received significantly more attention over the last few decades , emerging with increasing frequency and causing the majority of notable disease outbreaks in this century, including the COVID-19 pandemic . As human activities and shifting climate patterns induce changes in the environment that alter habitat and range of reservoir species , the potential for human and animal interactions will increase and enhance the opportunity for spillover . Thus, any emergency response preparedness planning must take into account the function and coordination of agencies across the sectors of human, animal and environmental health. Within the Commonwealth of Pennsylvania a table-top exercise was performed to evaluate a multi-agency response during a hypothetical zoonotic disease investigation. The exercise was evaluated by the participants to gain feedback on the overall process and lessons learned. Here, we describe the tabletop exercise scenario and the insights gai...

Abstract Infections caused by endemic viruses , and the vaccines used to control them, often provide cross-protection against related viruses. This cross-protection has the potential to alter the transmission dynamics and likelihood of emergence of novel zoonotic viruses with pandemic potential. Here, we investigate how changes in population immunity after the COVID-19 pandemic have impacted the likelihood of emergence of a novel sarbecovirus , termed SARS-CoV-X. We show that sera from patients with different COVID-19 immunological histories possess cross-neutralising antibodies against the spike (S) protein of multiple zoonotic sarbecoviruses . Mathematical simulations using these viruses show a significant reduction in their likelihood of emergence in populations with current levels of SARS-CoV-2 natural and vaccine-derived immunity, with the outcome determined by the extent of cross-protection and the R_0 of the novel virus. We also show that preventative vaccination programs agains...

Abstract Using a phylogenetic framework to characterize natural selection , we investigate the hypothesis that zoonotic viruses require adaptation prior to zoonosis to sustain human-to-human transmission . Examining the zoonotic emergence of Ebola virus, Marburg virus, influenza A virus, SARS-CoV, and SARS-CoV-2 , we find no evidence of a change in the intensity of natural selection immediately prior to a host switch , compared with typical selection within reservoir hosts . We conclude that extensive pre-zoonotic adaptation is not necessary for human-to-human transmission of zoonotic viruses. In contrast, the reemergence of H1N1 influenza A virus in 1977 showed a change in selection, consistent with the hypothesis of passage in a laboratory setting prior to its reintroduction into the human population, purportedly during a vaccine trial. Holistic phylogenetic analysis of selection regimes can be used to detect evolutionary signals of host switching or laboratory passage, providing ins...

ABSTRACT Coronaviruses (CoVs) pose a significant threat to public health , causing a wide spectrum of clinical manifestations and outcomes. Beyond precipitating global outbreaks, Human CoVs (HCoVs) are frequently found among patients with respiratory infections. To date, limited attention has been directed towards alphacoronaviruses due to their low prevalence and fatality rates . Nasal swab and serum samples were collected from a paediatric patient , and an epidemiological survey was conducted. Retrospective surveillance investigated the molecular prevalence of CoV in 880 rodents collected in the Republic of Korea (ROK) from 2018 to 2022. Next-generation sequencing (NGS) and phylogenetic analyses characterized the novel HCoV and closely related CoVs harboured by Apodemus spp . On 15 December 2022, a 103-day-old infant was admitted with fever, cough, sputum production, and rhinorrhea , diagnosed with human parainfluenza virus 1 (HPIV-1) and rhinovirus co-infection . Elevated AST/ALT le...

Abstract Understanding wildlife-pathogen interactions is crucial for mitigating zoonotic risk . Through meta-transcriptomic sequencing we profiled the infectomes of 1,922 samples from 67 mammalian species across China , uncovering a remarkable diversity of viral, bacterial, fungal, and parasitic pathogens. Of the 195 pathogens identified , 62 were novel , including a bi- segmented coronavirus in diseased lesser pandas, which we propose represents a new genus – Zetacoronavirus . The orders Carnivora and Rodentia exhibited the highest pathogen diversity and were implicated in numerous host-jumping events. Comparative analysis of diseased versus healthy animals revealed a trend of higher pathogen loads in the former, with possible differences in tissue tropisms. In total, 48 zoonotic and 17 epizootic pathogens were identified, with frequent cross-species transmission , emphasizing the potential for emerging public health threats. This study highlights the urgent need for wildlife pathogen...

 Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.12.11.627926v1?rss=1  Abstract In 2018, a single detection of a novel reassortant swine influenza A virus (swIAV) was made in Denmark . The hemagglutinin (HA) of the virus was from the H1N1 pandemic 2009 (H1N1pdm09) lineage and the neuraminidase (NA) from the H1N1 Eurasian avian-like swine lineage (H1N1av). By 2022, the novel reassortant virus (H1pdm09N1av) constituted 27 % of swIAVs identified through the Danish passive swIAV surveillance program. Sequencing detected two H1pdm09N1av genotypes ; Genotype 1 contained an internal gene cassette of H1N1pdm09 origin , Genotype 2 differed by carrying an NS gene segment of H1N1av origin . The internal gene cassette of Genotype 2 became increasingly dominant, not only in the H1pdm09N1av population, but also in other Danish enzootic swIAV subtypes . Phylogenetic analysis of the HA genes from H1pdm09N1av viruses revealed a monophyletic source , a higher substitution rat...