Section 2.1: Lessons from animal models (from DOI: 10.1016/j.jcv.2020.104372)
From publication: "SARS-CoV-2: Is it the newest spark in the TORCH?" published as J. Clin. Virol.; 2020 Apr 14 ; 127 104372. DOI: https://doi.org/10.1016/j.jcv.2020.104372
Section 2.1: Lessons from animal models
Animal models for SARS and MERS coronaviruses have been described, although relatively little attention has been devoted to the prospects for congenital or perinatal transmission in these studies. Murine coronavirus (M-CoV) is a species of coronavirus which infects mice, and experiments using a virulent strain of this virus in a pregnancy/challenge model demonstrated infection of both placenta and fetus in susceptible BALB/cByJ mice. Fetuses were infected during all three trimesters of pregnancy, although there was variation among different strains of mice, insofar as infection of resistant CD-1 mice was limited, with no fetal infection. Betaarterivirus suid 1 virus (formerly known as porcine reproductive and respiratory syndrome virus) is a porcine arterivirus related to coronaviruses and was commonly associated with early fetal demise in pigs in another study following challenge during pregnancy. Infection of cats with the coronavirus feline infectious peritonitis virus results in newborn kittens becoming carriers of the virus. Interestingly (and paradoxically), increased morbidity compared to controls was observed in kittens born to queens pre-sensitized with a vaccinia virus-vectored spike (S) protein vaccine, following challenge with feline infectious peritonitis. The mechanism of increased mortality in the vaccine group was not clear but may be related to vaccine-induced immune enhancement of infection. Antibody-mediated enhancement of coronavirus entry into Fc receptor-expressing cells has been described for antibodies targeting the receptor binding domain of the MERS coronavirus. These observations may be relevant to COVID-19 vaccines as they move forward in clinical evaluation.