Heartworm disease is a disease that occurs in dogs, cats, and other mammals. A heartworm is a part of the Nemotoda phylum. It is a parasitic roundworm that uses the host (animal which it is in) in order to grow. In the animal, the parasitic roundworm is safe and receives a steady supply of nutrients. Heartworms usually reside in the arteries of the lungs or the right side of the heart. Heartworm disease can have a fatal effect on the host and can rapidly spread from animal to animal.
It is very difficult to detect signs of Heartworm in the earlier stages. In fact, animals will show no symptoms of being infected. As soon as the Heartworms have grown in number and matured, symptoms of weight loss, weakness, tiredness, and decreased appetite will be visible. Heartworm tends to have a greater effect on dogs in comparison to cats. This is because in cats fewer worms are able to mature into adults.
Heartworm is usually detected by blood tests. The problem with blood tests is that they are only able to detect the heartworms after approximately seven months of infection. The two types of blood tests used are the antigen detecting tests and the microfilaria detection tests.
Heartworm is caused by mosquitoes which are responsible for the transmission of the disease. The cycle begins when an infected dog for example, is bit by a mosquito. The infected dog contains microfilariae (the initial stage of a heartworm). As the mosquito comes in contact with the dog, it too becomes infected by the microfilariae. The microfilariae mature into larvae inside of the mosquito. The mosquito then will continue going from animal to animal. As the mosquito feeds, it transports the larvae. From there, the larvae burrow their way inside until they reach the blood stream. In dogs, it takes about six months for the heartworm to fully mature. In cats, it takes approximately seven to eight months. Once the heartworm is mature, it produces offspring and the cycle continues.
In dogs, a medication called adulticide is used to treat Heartworm. Adulticide is injected into the muscle. It essentially kills the heartworms. A number of injections need to be given. It is best for dogs to be hospitalized at this time. It usually takes about two months for dogs to recover in which exercise should be limited.
As for cats, there is no real treatment available for them. Cats are usually less susceptible to the disease in general. Most cats are actually able to rid themselves of the disease. However, this can result in cats not responding well to the dead worms inside of their body. This reaction can actually be life threatening.