Unlike the North, where it is common for dogs to be given heartworms prevention during the spring and summer and not in the winter, southeastern weather is not cold long enough to kill mosquitoes, which are heartworm carriers. Mosquitoes transmit heartworms by taking blood from one heartworm-infected dog and injecting it into another dog. The juvenile heartworms transported by the saliva of the mosquito then multiply rapidly in the bloodstream. The lungs are blocked as well, and in some cases the dog fatigues quickly in exercise or coughs. In a more advanced stage, the abdomen of the dog may swell due to fluid accumulation.
Preventative medication is available in three types.
This is the oldest of the three commonly used treatments today, but the owners who use Filaribits find their dogs look forward to the pill as if it were a treat. Several manufacturers produce a second treatment method under the common names Heartguard, Interceptor and Sentinel. The external option that Revolution offers may be an asset if the dog shows apprehension about taking pills. Frontline and Advantage treat external threats fleas and some parasites, but not heartworms. A short test detects a dog's heartworm infection and is available at the local veterinarian.