Prevention is key against biting insects

No vaccines are yet available to protect humans against outbreaks of mosquito- and tick-borne illnesses like West Nile virus and Lyme disease.

Prevention remains the best defense. Chances are good you'll minimize the threat by observing the following 'five D's':

' Dusk until dawn. Reduce the amount of time spent outdoors when the mosquitoes apt to transmit infectious diseases are most active.

' Drain standing water. Keep a tidy yard.

Mosquitoes need water to reproduce. Overturn such things as stagnant wading pools and pet dishes or saucers beneath potted plants. Clear clogged rain gutters. Haul away discarded tires and other containers that can capture even a few ounces of rainwater. Change the water at least weekly in birdbaths.

If you live near blacklegged or deer ticks whose bite is known to convey Lyme disease, then mow lawns short, clear brush and leaf litter away from buildings.

' Dress appropriately.

Wear long-sleeved shirts and long pants in areas frequented by mosquitoes and ticks. Tuck pant cuffs into the tops of your socks or shoes to create a tick barrier. Drape mosquito netting over infant carriers and wear a head net. Avoid dark or bright clothing, which often attracts biting insects.

' Doors and barriers.

Repair screens on doors and windows to prevent mosquitoes and other biting insects from gaining entry into your home.

' DEET and other insect repellents.

Apply insect repellent if you are outdoors for any period of time.

'People dislike repellents in general and DEET in particular, but DEET is the gold standard of anything out there,' said Joe Conlon, a technical advisor to the American Mosquito Association and a former Navy medical entomologist.

Newer blends have a better feel, he said. Several other EPA-approved compounds are available commercially and are proving to be good alternatives to DEET, the U.S. Centers for Disease Control and Prevention says.