Feline coronavirus is an enveloped single-stranded RNA virus that occurs as two pathotypes: feline enteric coronavirus (FECV), defined as the “ubiquitous enteric biotype,” and feline infectious peritonitis virus (FIPV), the “virulent biotype” that causes FIP in individual cats.84

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URL: https://www.sciencedirect.com/science/article/pii/B9780702053184000073