susceptible-infected-recovered-susceptible (SIRS) model of the epidemiology of feline leukemia virus is formulated and analysed. The dynamics of the disease are dramatically different in no-risk, low-risk and high-risk subpopulations of asocial, free roaming, and multiple cat household cats. Among low risk ( < 1% prevalence) free roaming cats, the model predicts than an effective immunization rate of 4% year−1, or an effective removal rate of 8% year−1are adequate to control the disease completely. Under higher risk (10% prevalence) conditions, an effective immunization rate of 23 –72% year−1or a removal rate of 60 –145% year−1are required for control. At very high (30%) prevalance rates, even heroic measures may not suffice to substantially reduce disease prevalance: a vaccination rate of 100% year−1even if attainable, would only slightly reduce disease prevalence from 30% to 29%. We conclude that the current estimated effective feline leukemia virus immunization rate of 11 –19% of the general population is inadequate to provide herd immunity in the subpopulation of cats which are genuinely at risk of infection. A substantial increase in the vaccination rate and/or intensification of test and removal efforts in the at risk population would be required to attain an effective level of protection.
Lubkin, S. R., Romatowski, J., Zhu, M., Kulesa, P. M., & White, K. (1996). Evaluation of feline leukemia virus control measures. Journal of Theoretical Biology, 178(1), 53-60. https://doi.org/10.1006/jtbi.1996.0006