A Field Trial to Assess the Effect of Vaccination against Feline Herpesvirus, Feline Calicivirus and Feline Panleucopenia Virus in 6-Week-Old Kittens

Abstract

A trivalent (feline panleucopenia, feline herpesvirus, feline calicivirus), modified live, commercially available cat vaccine was used at either 6, 9 and 12 weeks of age (early schedule) or 9 and 12 weeks of age (conventional schedule), and the serological response to vaccination was assessed. The level of maternally derived antibody present at 6 weeks of age was also established. The use of early vaccination at 6 weeks of age induced an antibody response to each virus by 9 weeks of age in a significant proportion of kittens compared with unvaccinated littermates. There was no difference between the conventionally and early-vaccinated groups in terms of antibody response to any antigen by 12 and 15 weeks of age.

Feline calicivirus

“…Some are licensed for earlier use [21]. There is now evidence to suggest that not all kittens are able to respond to vaccination at 12 weeks of age, such that under some circumstances, later kitten vaccinations may be needed to overcome persistent MDA [21,47].…”

Feline herpesvirus

“…However, there is considerable individual variation. In a more recent study, 25% of kittens had antibody titres of < 1 in 4 at six weeks of age, and such kittens may respond to early vaccination [18]. However, in some individuals, MDA may still be at interfering levels at 12-14 weeks of age [18,72].…”

“…In a more recent study, 25% of kittens had antibody titres of < 1 in 4 at six weeks of age, and such kittens may respond to early vaccination [18]. However, in some individuals, MDA may still be at interfering levels at 12-14 weeks of age [18,72]. It should also be noted that low levels of MDA do not necessarily protect against subclinical infection and latency [34].…”

“…Intranasal vaccines used in conjunction with parenteral vaccine on entry into shelters have reduced the severity of upper respiratory disease in such establishments [21]. They have also been advocated for use in young kittens, to induce protection in the face of MDA, although there is evidence that some injectable vaccines may also be effective at an early age [18,36,64].…”

“…For most situations, the only reasonable course is to attempt disease control, largely by ensuring queens are regularly vaccinated, reducing stress, isolating queens and their kittens, and considering early weaning kittens into isolation or initiating kitten vaccination at an earlier age [18,39]. In some cases, it may be necessary to reduce the number of cats in the colony.…”