Background: This study reassesses the rate of vaccine associated adverse events (VAAE) and risk factors for VAAE in pet cats. The results may help inform veterinarians in the application of feline vaccination guidelines and help decrease risk of disease spread and outbreaks.
Objective: To determine the rates of VAAE in cats post vaccination. To determine possible risk factors associated with VAAE. We hypothesize that there will be a low rate of VAAE. Animals: Total of 1,543,413 vaccinated cats.
Methods: Retrospective cohort study of medical records obtained from Banfield Pet Hospital in the United States. Cats included those vaccinated with FVRCP, FeLV and/or rabies vaccine from 2015 to 2022. Medical records were searched for VAAEs using selected diagnosis codes (i.e. vaccine reaction, allergic reaction, dyspnea, vomiting, etc). Information was gathered about VAAE within 2 time windows: 0-3 and 4-15 days post-vaccination.
Results: 28,263 (0.8%) of cats vaccinated had a reported adverse reaction. VAAEs were most commonly reported within 3 days of vaccination. Increasing the number of vaccines administered at the vaccination visit was not associated with increased VAAE risk. Most VAAEs were associated with the rabies vaccine, and vaccines administered with rabies vaccine also had higher percentage of VAAEs than other combinations or sole vaccines.
Conclusions: Although overall VAAE rates were low, veterinarians should consider the finding that rabies vaccine may be more commonly associated with VAAE when creating vaccination strategies.
