Abstract
Viral infections with pandemic potential pose a significant threat to public health and animal health, with climate change increasing the risk of cross-species viral transmission.1,2 The health risks associated with infections caused by novel and existing viruses require a better understanding of the evolutionary ecology of these viruses in human and animal populations. Detection of SARS-CoV-2 in several animal species, including companion animals and wildlife, highlights the importance of carrying out surveillance of this new virus.3,4 Marine mammals may be susceptible to SARS-CoV-2 infection after being exposed to the virus via wastewater and marine debris, but this requires further investigation.5 Similarly, infections caused by avian influenza (AI) viruses have impacted wild populations, with reports of mass mortality events in Peruvian pelicans and sea lions being recently published.6-8 Furthermore, the adaptation of avian influenza viruses to mammals increases the risk of human transmission.6 Currently, SARS-CoV-2 and AI viruses may pose a threat to the health of the marine mammal populations, while wild mammals may also serve as reservoirs for zoonotic spread of these viruses; therefore, this study aimed to investigate the presence of AI and SARS-CoV-2 viruses in biological samples collected from Irish stranded seals.
From June to November 2023, faecal and nasal swabs were collected from harbor seal (Phoca vitulina) and grey seal (Halichoerus grypus) pups admitted to Seal Rescue Ireland (SRI) rehabilitation centre. Samples collected from 51 animals were processed at the Central Veterinary Research Laboratory of the Department of Agriculture, Food, and the Marine and tested by real-time reverse-transcription polymerase chain reaction for SARS-CoV-2 and AI.9,10 All 34 animals for which results are currently available tested negative for both viruses. Further testing is ongoing on the remaining samples.
While the negative results of SARS-CoV-2 and AI testing highlight the current absence of active infection/shedding of SARS-CoV-2 and AI viruses within the studied population, it does not rule out the circulation of these viruses in the wider population of seals in Irish waters. Ultimately, these preliminary results can provide baseline data that will inform the surveillance efforts warranted to monitor the ecological dynamics of SARS-CoV-2 and AI in the Irish marine ecosystem.
*Presenting author
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