Respiratory disease in cats associated with human-to-cat transmission of SARS-CoV-2 in the UK

Hosie, Margaret J; Epifano, Ilaria; Herder, Vanessa; Orton, Richard J; Stevenson, Andrew; Johnson, Natasha; MacDonald, Emma; Dunbar, Dawn; McDonald, Michael; Howie, Fiona; Tennant, Bryn; Herrity, Darcy; Da Silva Filipe, Ana; Streicker, Daniel G; Willett, Brian J; Murcia, Pablo R; Jarrett, Ruth F; Robertson, David L; Weir, William

Two cats from different COVID-19-infected households in the UK were found to be infected with SARS-CoV-2 from humans, demonstrated by immunofluorescence, in situ hybridisation, reverse transcriptase quantitative PCR and viral genome sequencing. Lung tissue collected post-mortem from cat 1 displayed pathological and histological findings consistent with viral pneumonia and tested positive for SARS-CoV-2 antigens and RNA. SARS-CoV-2 RNA was detected in an oropharyngeal swab collected from cat 2 that presented with rhinitis and conjunctivitis. High throughput sequencing of the virus from cat 2 revealed that the feline viral genome contained five single nucleotide polymorphisms (SNPs) compared to the nearest UK human SARS-CoV-2 sequence. An analysis of cat 2’s viral genome together with nine other feline-derived SARS-CoV-2 sequences from around the world revealed no shared catspecific mutations. These findings indicate that human-to-cat transmission of SARS-CoV-2 occurred during the COVID-19 pandemic in the UK, with the infected cats developing mild or severe respiratory disease. Given the versatility of the new coronavirus, it will be important to monitor for human-to-cat, cat-to-cat and cat-to-human transmission.