I do know that there has been research done that showed that the hoarding cases (involved in the study) had an 8% rate of both FIV & FeLV in the hoarding cats versus the average rate of 2.5-5% and 2-3%respectively in the general population. It's higher, but not massively higher. Rates are also generally higher in sicker cats than healthy ones, so this tracks as hoarding cats are also usually much sicker with often multiple infections. Things like calicivirus, URI, giardia, coronavirus are much more prevalent in hoarding cats at rates as high as 56% (for giardia) and calicivirus at 80%.
We don't take the large hoarding cases at our rescue, but we tend to focus FIV/FeLV testing on cats showing signs of things like: bite wounds, dental issues, skin infections, persistent or recurring fevers, and urinary/bladder problems, especially if it involves older, unneutered males. Sometimes also animals with initially "mysterious" underlying health conditions.
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Michelle Flowers
Foster Program Manager
Seattle Area Feline Rescue
UW-AAB
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