Preliminary investigation on feline coronavirus presence in the reproductive tract of the tom cat as a potential route of viral transmission

Abstract

Objectives Feline infectious peritonitis (FIP) is an immune-mediated disease initiated by feline coronavirus (FCoV) infection. To date, the only proven route of transmission is the faecal-oral route, but a possible localisation of FCoV in the reproductive tract of tom cats is of concern, owing to the involvement of the male reproductive tract during FIP and to the presence of reproduction disorders in FCoV-endemic feline catteries. The aim of the study was to investigate the presence and localisation of FCoV in semen and/or in the reproductive tract of tom cats, and its possible association with seroconversion and viraemic phase. Methods Blood, serum, semen and/or testicle samples were obtained from 46 tom cats. Serology was performed on 38 serum samples, nested reverse transcriptase PCR (nRT-PCR) and reverse transcriptase quantitative PCR (RT-qPCR) were performed on 39 blood samples and on 17 semen samples, and histology, immunohistochemistry and nRT-PCR were performed on 39 testicles. Results Twenty-four of 38 serum samples were positive on serology. Semen samples were negative on RT-PCR and RT-qPCR for FCoV, while all blood samples were negative at both molecular methods, except for one sample positive at RT-qPCR with a very low viral load. All testicles were negative at immunohistochemistry, while six were positive at nRT-PCR for FCoV. Serology and blood PCR results suggest that the virus was present in the environment, stimulating transient seroconversion. FCoV seems not to localise in the semen of tom cats, making the venereal route as a way of transmission unlikely. Although viral RNA was found in some testicles, it could not be correlated with the viraemic phase. Conclusions and relevance In the light of these preliminary results, artificial insemination appears safer than natural mating as it eliminates the direct contact between animals, thus diminishing the probability of faecal-oral FCoV transmission.

A meta-analysis of accuracy and sensitivity of chest CT and RT-PCR in COVID-19 diagnosis

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Feline Infectious Peritonitis: European Advisory Board on Cat Diseases Guidelines

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COVID-19 and male reproductive system: pathogenic features and possible mechanisms

“…One import point was to know the transmission of SARS-CoV-2 through the semen (Patel et al 2021 ). In a systematic review, it was emphasized that while SARS-CoV-2 might induce male infertility, there we no epidemiological evidence to confirm the sexual transmission of this virus (Tur-Kaspa et al 2021 ) The orchitis and testicular damages due to infection by the CoVs family have been reported in humans (e.g., SARS-Co) (Xu et al 2006 ) and animals (e.g., feline CoV) (Sigurðardóttir et al 2001 ; Stranieri et al 2020 ). While the various pathological characteristic with testicular damage and germ cell destruction was clearly observed in these cases (Xu et al 2006 ), the presence of virus in the testis and direct infection of tissue is still the subject of debate due to conflicting findings (Ding et al 2004 ; Gu et al 2005 ; Xu et al 2006 ).…”