The Leptospirosis vaccine is the most common culprit of causing adverse reactions. Plus, it's very ineffective. The vaccine only protects against a couple of the many strains of the bacteria. And although it is around, it's relatively rare. Many of the more informed vets have stopped giving Lepto shots for these reasons.
There is now a vaccine available for Lyme disease. However, a good number of vets refuse to use it. The vaccine causes many side effects. Vets state that it's actually easier treating the disease itself. Also, there's no reason to have your pet vaccinated for Lyme unless you live in a tick infested area. But dogs who live in these areas often have a natural immunity, which is stronger, so giving the vaccine is pointless.
Corona produces symptoms somewhat like mild Parvo, however most dogs recover quickly, with little treatment. The vaccine has never been proven effective. Very few Veterinary Colleges (which lead the way in medical research) use the vaccine. |