Traditionally the interscapular/dorsal cervical spine region has been used for vaccine administration in cats. Following the emergence of feline injection site sarcomas (FISS), concerns over vaccine safety and controversy about the locations used for vaccine administration have arisen.

As part of a large study in relation to the risk factors for and the incidence of FISS in the UK, a questionnaire concerning vaccination protocols was distributed to practices enrolled in the study. One of the questions asked which sites were commonly used for feline herpes/calicivirus (FHV/FCV), feline panleukopenia (FPV), feline leukaemia (FELV), Chlamydophila (CHL) and rabies (RAB) vaccination. A schematic diagram of a cat was provided for each antigen, and the vets were asked to mark the site they used with an 'X'. For analysis, the cat diagram was divided into 7 areas--interscapular/dorsal cervical region (IS), left forelimb (LF), right forelimb (RF), right flank (RFL), right hindlimb (RH), left hindlimb(LH), and left flank (LFL).

The questionnaire was distributed to 366 practices. The initial response rate was 43% before any reminders were sent out, and 155/158 practices had answered the questions regarding the location of vaccine administration. Not all practices provided an answer for every antigen. 93.5% (145/155) of practices used the IS region for administration of FHV/FCV and FPV vaccines; other sites used included RH (0.6%), LH (0.6%), and LFL (1.3%). 86.9% (133/153) of practices used the IS region for administration of FELV vaccines; other sites used included LF (0.6%), RF (0.6%), RFL (0.6%), RH (1.3%), LH (3.3%) and LFL (2%). 92.9% (91/98) of practices used the IS region for administration of CHL vaccines; other sites used included RH (1%), and LFL (2%). 93.7% (133/142) of practices used the IS region for administration of RAB vaccines; other sites used included LF (0.7%), RH (2.1%), LH (0.7%), and LFL (0.7%).

These data suggest that the majority of practices in the UK commonly use the interscapular/dorsal cervical spine region for the administration of vaccines to cats.