Antibody response and virus survival in cats vaccinated against feline leukaemia

Abstract

WE have shown that leukaemia virus can be transmitted from cat to cat by contact or aerosol¹. There is also substantial epizootiological evidence that such transmission occurs in natural conditions^2,3. Horizontal transmission occurs because feline leukaemia virus (FeLV) replicates not only in cells of the haematopoietic system but is also found in large amounts in respiratory and alimentary mucous membranes and is excreted in the urine¹. It is therefore not surprising that the infection in cats is fairly common. In the City of Glasgow we found that about one third of the cats sampled had antibodies against FeLV (mean titre = 2; ref. 4). We recently examined 100 young cats from the surrounding countryside and found antibody in six (mean titre = 20). These facts indicate that vaccination would be valuable and we have evidence that it is feasible. Here we report on the use of FeLV-infected cells to produce an immune response of a high level in cats.