Principles of Feline Coronavirus Antibody Detection

Serological tests do not confirm FIP because antibodies do not distinguish between non-variant FCoV infection and FIP virus infection. Many healthy cats are antibody positive for FCoV, but most of these cats do not have FIP. In addition, seropositivity does not distinguish between active infection and past infection.

Non-FCOVs (e.g., canine coronavirus and porcine transmissible gastroenteritis virus) related antibodies can cross-react with FCOV antibodies, further reducing detection specificity.

Seroconversion occurred 1 to 3 weeks after FCoV exposure.

Positive coronavirus antibody does not confirm FIP, and absence of FCoV antibody does not preclude a diagnosis of FIP.

Many commercial diagnostic laboratories test antibody titers for FCoV, however, the methods vary. So the results can't be compared between LABS. For example, in a detection procedure, both cat and non-cat virus antigens will affect the titer value, the lowest and highest titer levels.

Antibody titer levels of FCoV were quantitatively measured using a reliable commercial diagnostic laboratory. Avoid the use of rapid in-hospital enzyme-linked immunosorbency (ELISA) tests, which report only positive or negative results and do not quantify antibody titers.

The 7B gene antibody ELISA test has been used commercially as a "FIP-specific test". However, the mutation is not specific for FIP, and the test does not offer an advantage over traditional serological tests.

The serum or plasma used for antibody detection of FCoV can be refrigerated or stored at minus 20 ° C without affecting the detection.

Antibodies to FCoV can also be tested with exudate, CSF, or anterior chamber fluid. Some studies have suggested that these tests have more diagnostic value than serological tests, but these claims are unreliable.