West Nile Virus. Those three words have a growing number of people on the run—to the indoors, that is. The mosquito-borne illness has become a seasonal near epidemic in North America, erupting in the summer and continuing into autumn. The virus, which first appeared in the United States in 1999, has spread to every state except Washington and is most prevalent in California, Colorado, Arizona, New Mexico, Texas, and Louisiana. In 2004, West Nile virus caused 88 deaths in humans (down from 264 in 2003).

Infected mosquitoes spread West Nile virus after contracting it from infected birds. The virus causes a range of symptoms in humans, from mild fever to permanent neuromuscular damage and even death. Luckily, less than 1 percent of people infected with West Nile develop severe symptoms.

Still, prevention is key to staying healthy. Here are some tips for keeping the buggers at bay.

  • Go light>> Dark colors, especially blue, magnetize mosquitoes—that’s another reason to wear a lighter clothing palette, which also keeps you cool. Khakis and light-colored neutrals reflect strong light particularly well to help keep mosquitoes away.
  • Use natural repellents>> If you are concerned about DEET, try natural alternatives. Citronella, an extract of lemongrass, is one of the few repellents registered by the Environmental Protection Agency for human application. Mark Blumenthal, executive director and founder of the American Botanical Council, has used citronella in the United States and beyond with great success. “I haven’t used chemical repellents for more than ten years, even when schlepping through the jungle,” Blumenthal says. “The downside is that it doesn’t last as long as DEET, so you have to reapply every couple of hours. But I would prefer to reapply [something natural] rather than use DEET.” Other essential oils that act as natural repellents are clove (Syzygium aromaticum), thyme (Thymus vulgaris), and peppermint (Mentha piperita). A word of caution, however: Essential oils must be diluted with a carrier oil before application to skin.
  • Indulge in garlic>> Odiferous garlic can act as a repellent—just ask your friends. No, really, eating a clove or two can work to ward off mosquitoes, but the herb is most effective as an adjunctive or complementary therapy with other natural repellents, according to Blumenthal.
  • Have sense about scents>> How sweet you smell may determine how often you get bit. (Note: Reread the garlic tip.) Scented toiletries and laundry detergents, especially with heavy floral notes, attract bugs. Instead, use unscented products or peppermint soap to help reduce unfavorable attention.
  • Keep dry>> Mosquitoes are drawn to water, whether to the smell of sweat and the moistness of perspiration, or to stagnant puddles in your yard. So after your daily hike in the hills, clean up and towel off before you hit the hammock. Additionally, standing water can be a breeding ground for mosquitoes. Unclog roof gutters, change water in birdbaths frequently, and remove old tires or anything else that holds water.
  • Avoid rush hours>> Be alert to peak mosquito hours, which tend to be at dawn and twilight. Take care to use extra repellent, or stay inside during these times.
  • Screen carefully>> Install or repair window and door screens to keep mosquitoes out of your home.