Every day across Texas 100’s of dogs are euthanized in shelters simply because they are heartworm positive. Heartworm disease is spread by mosquitoes and can be contracted year-round because of our warm climate. Although it is cheap to prevent infection with the use of monthly o*** preventative or 6 month injections, it has been very expensive to treat once a dog has been infected. This high cost has kept otherwise wonderful dogs from being adopted, and sometimes dogs are even surrendered to shelters for euthanasia because of advanced heartworm disease. This disease is not contagious to humans but an infected dog poses a risk to other dogs in the area that are not kept on monthly heartworm preventative.