Mosquito bites cause itching and irritation, and scratching may result in infected sores. Mosquitoes also transmit serious and sometimes fatal diseases to humans and their pets. Encephalitis is an inflammation of the brain that can be caused by viruses. Symptoms of encephalitis can range from mild to severe. Symptoms include rapid onset of severe headaches, high fever, and mental disturbances such as confusion, irritability, tremors, stupor and coma. Severe cases sometimes end in death or with survivors suffering permanent loss of limb function, reduction of intelligence and/or emotional instability.

Not all types of encephalitis viruses are carried by mosquitoes. However, mosquitoes carry at least two types of encephalitis viruses that cause human disease in Texas. West Nile and St. Louis encephalitis are normally an infection of wild birds but can be past to other mammals by mosquitoes; in humans both viruses affect mainly individuals over 50 years old or those with weakened immune
systems.

Mosquitoes can also infect dogs with heartworm. The worms live in the heart and can severely weaken or kill the dog. Although difficult to treat, this disease is easily prevented by medication that can be prescribed by your veterinarian.

All three of the viruses mentioned above are transmitted by a species of Culex mosquito. Culex mosquitoes, which breed in places like ditches, open septic systems, discarded tires, unused pools, and other assorted containers, particularly in shady areas. Mosquito larvae or "wrigglers" must live in still water for five or more days to complete their growth before changing into adult biting mosquitoes capable of transmitting disease. Often, the number of mosquitoes in an area can be reduced by removing sources of standing water. Hundreds of mosquitoes can come from a single discarded tire and thousands from an untreated swimming pool.

Is Your Home a Friendly Environment for Mosquitos?