By Richard Harkness
Enquirer contributor

Question: We enjoy outdoor activities and I'm worried about the return of West Nile virus this year. If one of us gets it, can we transmit it to another family member? What is the best mosquito repellent and is it safe?

Answer: As warmer weather slides in, we can expect to see larger numbers of mosquitoes and increased West Nile virus activity.

Birds carry the virus, which can be transmitted to mosquitoes that bite them. In turn, humans and animals can get the virus when they are bitten by infected mosquitoes.

The good news is that even in areas where the virus is circulating, very few mosquitoes harbor it.

To answer your first question, West Nile virus does not appear to be transmitted from person to person or from animal to person.

As to your second question, the most effective and best-studied insect repellent is called DEET. You apply it to exposed skin.

You may wonder what strength of DEET to use.

According to a recent study, here's how it breaks down:

• 23.8 percent DEET provided an average of 5 hours of protection from mosquito bites.

• 20 percent DEET provided almost 4 hours of protection.

• 6.65 percent DEET provided almost 2 hours of protection.

• 4.75 percent DEET provided about 1.5 hours of protection. (Natural product advocates: 2 percent soybean oil provided the same protection.)

Knowing this, you can choose a product based on how long you plan to stay outdoors.

DEET appears to be safe when used according to label directions. The American Academy of Pediatrics recommends products containing no more than 10 percent DEET on children ages 2 to 12 years.

Mosquitoes are most active around dusk and dawn, so be sure to apply repellent when outdoors at these times. Wear long-sleeved shirts, long pants and socks. Don't apply DEET to skin under clothing.

Mosquitoes lay their eggs in standing water such as ponds, roadside ditches and containers. Be sure to empty any containers of standing water around your house.

E-mail rharkn@aol.com