The Centers for Disease Control and Prevention recently recommended two new ingredients as mosquito repellents, picaridin and oil of lemon eucalyptus, marking the first time the agency has suggested anything other than the chemical DEET for mosquito bite prevention.
"We hope by giving people a wider range of options, that some nonusers might become interested in using repellents," said Emily Zielinski-Gutierrez, a behavioral scientist at the CDC's division of vector-borne infectious diseases.
DEET, in use for more than 40 years, has long been the standard in mosquito protection, but many Americans have not been buying products that contain the chemical. This is due partly to lingering consumer fears -- largely unwarranted, the agency says -- about the safety of DEET. Only 40 percent of Americans report regularly using mosquito repellents, says the CDC -- even though West Nile Virus has been found in 47 of the 48 continental states and the District of Columbia.
West Nile virus and other mosquito-borne infections can result in serious illness or death; those older than 50 are more vulnerable to the severe effects of West Nile. The virus also can cause milder illness, and many people show no effects when bitten by an infected mosquito.
The CDC recorded 2,535 West Nile cases for last year, according to numbers that are not yet finalized, down from 9,862 in 2003. The number of deaths also dropped, from 264 in 2003 to 98 in 2004, according to the most updated reports.
CDC officials said they chose to act now because recent studies have reassured them of the safety and effectiveness of the two ingredients. Agency scientists reviewed existing literature and concluded there was sufficient evidence to safely recommend picaridin, a chemical used in other countries and sold in one U.S. product, and oil of lemon eucalyptus, a natural ingredient found in various lotions and sprays.
Both ingredients previously had been registered with the Environmental Protection Agency, which means that the EPA has evaluated them for safety and efficacy. The CDC recommends that people use repellents whenever they go outdoors during warm-weather months, particularly between dusk and dawn.
The CDC also reaffirmed its recommendation for DEET, calling it a "highly effective repellent option" in a statement.
"DEET is very safe and effective, but some people just can't use it" because of its powerful smell and, in some cases, skin irritation, said Noah Scheinfeld, assistant professor of dermatology at Columbia University.
|¢ Use just enough to cover all exposed skin and clothing, but don't apply to skin underneath clothing.¢ Don't apply to wounds, cuts or irritated skin.¢ Don't apply to mouth or eyes, and use lightly around the ears.¢ When you return indoors, wash repellent-covered skin with soap and water. Wash clothing that has repellent on it before wearing again.¢ Don't spray pump or aerosol repellents in enclosed areas.¢ Don't apply pump or aerosol products directly onto your face. Instead, spray hands and then rub the product onto your face, avoiding the mouth and eyes.¢ When applying to children, put on your own hands first and then use your hands to apply the repellent on to the child.|
Scheinfeld wrote an article examining the research into picaridin that was published last year in the Journal of Drugs in Dermatology.
Another repellent option is permethrin, which the CDC recommends only for use on clothing -- particularly clothes so thin that a mosquito might be able to bite through them, said Zielinski-Gutierrez. It is not to be sprayed directly onto skin, she said.
CDC officials emphasized the need for consumers to read product labels when selecting mosquito repellents. Some work longer than others and many need to be reapplied every few hours. You also may need to reapply the repellent if you perspire or get wet. A general rule of thumb is to reapply the product if you start getting bitten, Zielinski-Gutierrez said.
If you intend to use a repellent on children, be sure to confirm the product is OK for their age group. And infants under 2 months old shouldn't use any repellents, Zielinski-Gutierrez said.