Lyme disease is a tick borne disease that 1 in 10 dogs in La Porte County test positive for. We highly recommend this vaccine. The company will cover the cost of testing and treatment if your dog comes back positive on their Lyme test after being on this vaccine consistently. The bacteria can lay dominant in the body for years with no symptoms. The main symptom we see in dogs are limping, painful joints and lameness. This vaccine can be started at 9 weeks of age and requires a booster 2-3 weeks later. A yearly booster is required and MUST be done at least 13 ½ months after the last vaccine or the company will not cover it and the vaccine series will need to be restarted for the company to guarantee it.