Circulation and genetic diversity of Feline coronavirus type I andIIfrom clinically healthy andFIP‐suspected cats in China

Abstract

Feline infectious peritonitis (FIP) is a fatal infectious disease of wild and domestic cats, and the occurrence of FIP is frequently reported in China. To trace the evolution of type I and II feline coronavirus in China, 115 samples of ascetic fluid from FIP‐suspected cats and 54 fecal samples from clinically healthy cats were collected from veterinary hospitals in China. The presence of FCoV in the samples was detected by RT‐PCR targeting the 6b gene. The results revealed that a total of 126 (74.6%, 126/169) samples were positive for FCoV: 75.7% (87/115) of the FIP‐suspected samples were positive for FCoV, and 72.2% (39/54) of the clinically healthy samples were positive for FCoV. Of the 126 FCoV‐positive samples, 95 partial S genes were successfully sequenced. The partial S gene‐based genotyping indicated that type I FCoV and type II FCoV accounted for 95.8% (91/95) and 4.2% (4/95), respectively. The partial S gene‐based phylogenetic analyses showed that the 91 type I FCoV strains exhibited genetic diversity; the four type II FCoV strains exhibited a close relationship with type II FCoV strains from Taiwan. Three type I FCoV strains, HLJ/HRB/2016/10, HLJ/HRB/2016/11 and HLJ/HRB/2016/13, formed one potential new clade in the nearly complete genome‐based phylogenetic trees. Further analysis revealed that FCoV infection appeared to be significantly correlated with a multi‐cat environment (p < 0.01) and with age (p < 0.01). The S gene of the three type I FCoV strains identified in China, BJ/2017/27, BJ/2018/22 and XM/2018/04, exhibited a six nucleotide deletion (C4035AGCTC4040). Our data provide evidence that type I and type II FCoV strains co‐circulate in the FIP‐affected cats in China. Type I FCoV strains exhibited high prevalence and genetic diversity in both FIP‐affected cats and clinically healthy cats, and a multi‐cat environment and age (<6 months) were significantly associated with FCoV infection.

A Tale of Two Viruses: The Distinct Spike Glycoproteins of Feline Coronaviruses

“…From these studies, FCoVs corresponding to each serotype have been described: feline (serotype I or type I) and canine (serotype II or type II) [21,22]. While both serotypes have been categorized in FECV and FIPV forms, both of which can cause FIP, serotype I viruses are much more prevalent in cat populations and so are the leading cause of FIP [23][24][25][26]. Such viruses grow only poorly in cell culture and are hence understudied compared to serotype II viruses, which have arisen by independent recombination events with canine coronaviruses and replicate well in cell culture [27,28].…”

Oral Mutian®X stopped faecal feline coronavirus shedding by naturally infected cats

“…(Addie et al, 2012;Cave et al, 2004). Two FCoV genotypes are currently known: FCoV type I (FCoV-I), which is predominant in the field, (Addie et al, 2003;Li et al, 2019) and FCoV type II (FCoV-II), which derives from recombination between FCoV-I and canine coronavirus (Decaro and Buonavoglia, 2008;Herrewegh et al, 1998;Terada et al, 2014).…”

Development and evaluation of a SYBR Green I RT-qPCR assay for Feline Infection Peritonitis virus detection

“…However, infection with FCoV is associated with the development of the fatal and progressive disease manifestation of FIP in some cats [10]. Stem from its lethality, the difficulties in diagnosing FIP ante mortem and controlling the spread of FIPV, FIP is among the most serious viral infections in cats.…”