A subject of much debate in the field of immunology is the timing of booster injections. Based on a growing body of evidence, recommendations for booster vaccinations have been changing. In general, viral vaccines tend to stimulate longer immunity than bacterial vaccines. It is now believed that the protective response to vaccines for distemper, parvovirus, and rabies probably persists for several years following a vaccination series, and that booster shots can be given every three years instead of every year. This interval for booster shots may be extended even longer with the newer vaccines and updated research data on the duration of immunity.
On the other side of the scale, evidence also suggests that vaccines for parainfluenza, bordetella bronchiseptica and leptospirosis fail to protect for the full 12 months. These vaccines might need to be given twice a year, rather than annually, especially to dogs who are at increased risk. The best way to manage vaccinations is to work with your veterinarian to develop a customized vaccination schedule for your dog, based on your own dog’s health and risk factors.