Prevalence of Multiple RNA Virus Infections in Nine Types of Commonly Used Laboratory Animals in China

Introduction: Laboratory animals are widely used in biomedical research. Surveillance of naturally occurring virus in laboratory animals is important to fully understand the results of animal experiment, control laboratory-acquired infections among research personnel and manage viral transmission within laboratory animal populations. This study aimed to investigate the prevalence of multiple RNA viruses in laboratory animals commonly used in China.

Methods: We screened viral RNA for five different potentially zoonotic RNA viruses (astrovirus, coronavirus, hepevirus, hepatovirus and picornavirus) that can be transmitted via the faecal-oral route in 759 faecal samples collected from nine commonly used laboratory animals (mice, rats, monkeys, rabbits, pigs, dogs, ferrets, goats and tree shrews) in China. Viral RNA was screened by broad-spectrum reverse transcription polymerase chain reaction (RT-PCR) using primers annealing in genome-conserved regions. The laboratory mice and rats used in this study were specific-pathogen-free. The other laboratory animals were conventional animals.

Results: At least one selected virus was detected in each of the nine sampled laboratory animal types, except tree shrews. The total positive rates of viral RNA for astroviruses, coronaviruses, hepeviruses and picornaviruses in the selected laboratory animals were 4.3%, 7.6%, 8.0% and 1.1%, respectively. Among these, the positivity rates for hepevirus RNA in laboratory ferrets (41.3%) and rabbits (17.8%), astrovirus RNA in laboratory pigs (75.0%) and coronavirus RNA in laboratory ferrets (45.7%) were relatively high. Viral RNA for hepatovirus was negative in all selected laboratory animals. Co-infection with multiple viruses has also been observed in laboratory dogs, pigs, ferrets and rabbits.

Conclusions: Our findings highlight the need for the surveillance of natural viral infections in laboratory animals.