Investigation of SARS-CoV-2 infection in domesticated animals from COVID-19 affected households in Bangladesh

Abstract

The emergence and rapid global spread of the novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has sparked significant interest in understanding its zoonotic origins. This study aims to investigate animal and environmental samples in Bangladesh to identify the zoonotic source and reverse zoonosis of SARS-CoV-2. This research adopted a comprehensive approach to gather and analyze samples from various animal species, including cattle, sheep, goats, cats, and dogs that are peridomestic in nature or remain in close contact, ensuring biosafety and avoiding cross-contamination. SARS-CoV-2 or related coronaviruses were identified using immunological detection and real-time reverse transcription-polymerase chain reaction (RT-qPCR). A total of 1028 samples from different regions of Bangladesh were collected from cattle (552), sheep (135), goats (112), cats (118), and dogs (111), of which 465 were rectal, 363 nasal swabs, and 200 blood samples. The samples were collected from those areas where there were human records of COVID-19 during July 2021- December 2022. The blood samples were collected and immediately used for antibody screening. No positive samples were found in both antibody test screens and RT-qPCR in fecal and nasal swab samples. The study indicated no COVID-19 infection was found in domestic animals and pets despite staying in close contact with COVID-19 patients or households, suggesting a limited risk of transmission from these animals to humans within the studied context. It's possible that domestic animals are not significantly involved in the COVID-19 epidemic in natural environment exposure conditions.