ABSTRACT
A highly transmissible severe acute respiratory coronavirus 2 (SARS-CoV-2) caused the coronavirus diseases 2019 (COVID-19) pandemic, which resulted the highest morbidity and mortality rates among SARS-CoV and MERS-CoV. SARS-CoV-2 B.1.1.7 variant indicated the higher transmission among human-to-human and increasing hospitalisation. SARS-CoV-2 infection was observed in domestic animals showing human-to-pet transmission. In the current study, we report the first direct known human-to-cat transmission of the SARS-CoV-2 B.1.1.7 variant within the same family. Previous findings showed that companion animals can get infected by COVID-19 patients after 3-6 weeks; however, according to our molecular findings, the cat was infected by the viral variant at the same period. Moreover, B.1.1.7 infection caused and developed several clinical symptoms including cardiac and ocular abnormalities. Overall, our findings determined the first direct and high transmission ability of the B.1.1.7 variant from COVID-19 affected family members to cat. This result showed that the SARS-CoV-2 B.1.1.7 variant could have the highest transition capacity from human to domestic cat as shown for human-to-human. The governmental or worldwide policies should consider more detailed against the war with COVID-19 pandemic.