Please visit these links for more information on heartworm:
Heartworm Canine Heartworms and Preventing Disease – Veterinary Partner – VIN:
https://veterinarypartner.vin.com/default.aspx?pid=19239&id=11942142
Heartworm Infection in Cats – Veterinary Partner – VIN:
https://veterinarypartner.vin.com/default.aspx?pid=19239&id=4951471