Clinical and Molecular Relationships between COVID-19 and Feline Infectious Peritonitis (FIP)

Abstract

The emergence of severe acute respiratory syndrome 2 (SARS-CoV-2) has led the medical and scientific community to address questions surrounding the pathogenesis and clinical presentation of COVID-19; however, relevant clinical models outside of humans are still lacking. In felines, a ubiquitous coronavirus, described as feline coronavirus (FCoV), can present as feline infectious peritonitis (FIP)—a leading cause of mortality in young cats that is characterized as a severe, systemic inflammation. The diverse extrapulmonary signs of FIP and rapidly progressive disease course, coupled with a closely related etiologic agent, present a degree of overlap with COVID-19. This paper will explore the molecular and clinical relationships between FIP and COVID-19. While key differences between the two syndromes exist, these similarities support further examination of feline coronaviruses as a naturally occurring clinical model for coronavirus disease in humans.

Feline infectious peritonitis: A comprehensive evaluation of clinical manifestations, laboratory diagnosis, and therapeutic approaches

“…Feline infectious peritonitis (FIP) and COVID-19 are two distinct diseases caused by different coronaviruses and affecting different species [ 1 ]. Common features are observed in both FCoV and SARS-CoV-2, such as the rapid spread of infection, the potential to decrease infection rates by isolating infected patients, and the shared efficacy of comparable anti-inflammatory or antiviral compounds [ 1 , 2 ].…”

“…Feline infectious peritonitis (FIP) and COVID-19 are two distinct diseases caused by different coronaviruses and affecting different species [ 1 ]. Common features are observed in both FCoV and SARS-CoV-2, such as the rapid spread of infection, the potential to decrease infection rates by isolating infected patients, and the shared efficacy of comparable anti-inflammatory or antiviral compounds [ 1 , 2 ]. A virulent FCoV, or feline infectious peritonitis virus (FIPV), is disseminated via the mononuclear phagocyte system, while a nonvirulent FCoV is associated with asymptomatic persistent enteric infections [ 3 ].…”

“…A virulent FCoV, or feline infectious peritonitis virus (FIPV), is disseminated via the mononuclear phagocyte system, while a nonvirulent FCoV is associated with asymptomatic persistent enteric infections [ 3 ]. Host factors involved in FIP were stressful events, including surgery, rehoming, multi-cat households, and retrovirus co-infection, which may increase the susceptibility of cats to developing FIP [ 1 – 3 ].…”

Retrospective study and outcome of 307 cats with feline infectious peritonitis treated with legally sourced veterinary compounded preparations of remdesivir and GS-441524 (2020–2022)

“…FIP associated with effusion development (especially in the abdominal cavity) is the most common type of FIP encountered. 7 – 16 A range of other systemic signs can occur, such as pyrexia, inappetence, lethargy, 9 , 12 , 13 , 17 , 18 abdominal lymphadenopathy, 9 , 19 , 20 ocular signs 21 , 22 and/or neurological signs. 23 , 24 A definitive diagnosis usually relies on demonstration of the FCoV antigen or RNA in association with typical FIP histopathological changes, but a range of supporting diagnostic evidence can be obtained from haematology, serum and/or fluid sample (eg, effusion) biochemistry (eg, hyperglobulinaemia, increased alpha-1-acid glycoprotein [AGP], serum amyloid A, hyperbilirubinaemia, reduced albumin to globulin [AG] ratio), cytology (pyogranulomatous inflammation) and FCoV antigen or FCoV RNA detection (on samples such as effusions or fine-needle aspirates [FNAs]).…”

Detection of anti-feline infectious peritonitis virus activity of a Chinese herb extract using geneLEAD VIII, a fully automated nucleic acid extraction/quantitative PCR testing system

“…Feline infectious peritonitis virus (FIPV) is a variant of non-pathogenic or benign feline enteric coronavirus (FECV) of feline coronavirus (FCoV), and specific mutations in the viral genome are thought to be important for the conversion from FECV to FIPV although the positions of the mutations necessary or sufficient for this conversion are not yet clear [ 6 , 13 ]. FCoV, including FIP, belongs to the genus Alphacoronavirus in the subfamily Coronavirinae while severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV-2 are in the genus Betacoronavirus in the same subfamily [ 10 ]. Since effective therapies or vaccines against FIPV are currently not available, more efficient methods to study FIPV are necessary to develop new treatment and/or prevention against the disease in cats.…”