how often do dogs need to be vaccinated for leptospirosis
For pups, the initial vaccine is administered at 12 weeks old and repeated two to four weeks later. For older puppies (over four months old) or adults receiving the leptospirosis vaccine for the first time, two doses two to four weeks apart are recommended. Annual revaccination is recommended for dogs at sustained risk of exposure to the leptospirosis disease-causing organism. Dogs at exceptionally high risk should be vaccinated every six to nine months throughout the period of their continued high risk of exposure.