Since heartworms are transmitted by mosquitoes, why do I need to give heart worm prevention during the winter months?

Good question! The answer is for two reasons: 1) The risk is just too great. All it takes is ONE MOSQUITO BITE to transmit heartworms and cause heartworm disease. 2) The heartworm prevention products that we carry also protect against many common intestinal parasites, which dogs can be exposed to year-round. Intestinal parasites can cause weight loss and anemia, and in severe cases, death.