In October, 1847 was the first report of heartworm in a dog in The Western Journal of Medicine and Surgery.  Due to “low owner compliance in administering preventive medicines, people taking  their pet with  them when traveling, and a sudden surge of infected strays approximately 160 years later has spread heartworm to every state,” says John W. McCall, Ph.D., vice president of the American Heartworm Society. 

The cause of heartworm is a parasitic roundworm living in a dog’s lungs and heart. The female worms release their young – microfilariae – into the dog’s blood stream and are transferred to mosquitoes when they bite the dog. In the female mosquito the microfilariae mature into infective larvae which are transferred to another dog two weeks later, again through a mosquito bite. The adult worms are fully developed in the dog six months later.

 You can detect if your dog has  heartworm disease  with a blood test. Mild and severe heartworm cases often present symptoms such as exercise intolerance, coughing, and abnormal heart and lung sounds. Heartworm is potentially fatal if untreated.

 Even though, heartworm can be killed through a series of injections,  preventive oral and topical spot-on treatments are more economical for the owner and safer for the dog. There are several types of preventive drugs, including ivemectin, mibemycin, selamectin, moxidectin, and dethylcarbamazine. Always talk with your vet about choosing the preventive drug that’s right for your dog.

 Dogs can become infected the moment they are born, so preventive care should begin at 8 weeks of age and continued all year around.