IMPACT OF 2 FELINE RETROVIRUSES ON NATURAL-POPULATIONS OF DOMESTIC CAT

We compared the pattern of spread and the impact of two retroviruses, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) within natural populations of domestic cats. A four years epidemiologi cal study shows that FIV is present in three studied rural cat populat ions, whereas FeLV is absent in one out of the three, with no evolutio n in time for either virus. Factors influencing FIV transmission are d irectly linked to aggressive behavior, while factors influencing FeLV transmission are rather characteristic of amicable interactions. Resul ts of a deterministic model show that both infections are maintained i n the population as a stable equilibrium between susceptible and infec ted animals, slightly reduce the number of individuals at equilibrium, and have low transmission rates. Results of a long term dynamical stu dy indicate that the probability of dying from these viruses is low in natural conditions, and that, despite their presence, the size and st ructure of the populations remain stable. In conclusion, despite FIV a nd FeLV have different spread patterns (FIV infects and kills at-risk individuals, while FeLV infects individuals more indiscriminately), th e impact of both retroviruses on cat populations seems to be low.