As a concerned cat owner, have you heard of feline foamy virus (FFV or FeFV)? It is not listed in the excellent Cat Owner’s Home Veterinary Handbook and yet the AVMA in their online journal recently say that it is present in a high proportion of domestic cats. For example 64% of domestic cats in eight shelters have it in some US states. It is called a Spumavirus and it is a retrovirus.
To measure how widespread it is scientists use the word ‘seroprevalence’ which means the existence of the disease as evidenced by its presence in the cat’s blood (blood serum). I’ll presume that this refers to the existence of antibodies against the disease in the blood.
This is what Katie Burns wrote on Feb 12 2020 in JAVMA News:
Among domestic cats admitted to shelters because of nonowner surrender or that were involved in trap-neuter-return programs, the FFV seroprevalence was 75.0% in Southern California, 52.4% in Colorado, and 41.9% in Florida. Among pumas, the FFV seroprevalence was 69.1% in Southern California, 77.3% in Colorado, and 83.5% in Florida.
So FFV is everywhere in the domestic cat population. And it also infects mountain lions to the same level (78.6% of pumas in three states). There is transmission of the virus between domestic/feral cats and mountain lions. Transmission between domestic cats is said to be through ‘intimate social contact’ and less commonly aggressive behaviour i.e. biting.
So what the hell is it? Well, it seems that the reason why we don’t hear about it is because there are no symptoms of illness but I think this is work in progress. It is said to be ‘apathogenic’ meaning not pathogenic i.e. not capable of causing disease. So the virus is simply present in the body with no effect. Is that correct? It sounds odd that a disease does not cause disease!
However, the virus is still ‘poorly understood’. Can it work in conjunction with well know viruses such as FIV and FeLV and make them worse?
A study published in May 2008 on sciencedirect.com says that cats show no outward symptoms of disease but that an examination of the kidney and lung tissues of the cats by microscope showed changes. The researchers said that more work was needed to assess the significance of the finding.
It was referred to in a study as long ago as 1999. That study said that in domestic cats over 9-years-of-age it was present in over 70% of them. FFV seems to have been under the radar of concerned cat guardians. I sounds a bit like toxoplasmosis in terms of it’s asymptomatic behavior. But the question is whether FFV does have an impact on domestic cat health in hidden way.
Sources: JAVMA, 2 studies and dictionaries.
SOME MORE ON FELINE VIRUSES: