The summer mosquito season increases the threat of encephalitis, an untreatable, mosquito-borne virus that occasionally is fatal. Mosquitoes also can transmit the West Nile virus, a potentially serious illness that flares up in the summer and continues into the fall.
Encephalitis, an inflammation of the brain and spinal cord commonly known as “sleeping sickness,” can result in fever and headaches that can last two weeks. But in its severest form, particularly among the very young and very old, it can lead to confusion, paralysis, coma and death, says Stuart Cohen, an infectious disease expert at UC Davis Health System. Mosquito season runs from June through October in California.
To lower the risk of mosquito bites, Cohen suggests:
- Avoid being outdoors during the early morning and early evening, when mosquitoes are most active.
- Wear long-sleeved shirts or spray insect repellant with the active ingredient diethyltolumide on your clothing when you go outside.
- Empty all containers of water in your yard; a little water left in bucket can spawn 15,000 mosquitoes in one week.
- Cover swimming pools or clean them every day with filter skimmer.
- Put mosquito fish, which eat mosquito larvae, in ponds, fountains or other bodies of water that cannot be drained.
- Sleep under a mosquito net when camping in mosquito-infested areas.