Fight the bite: Advice for preventing mosquito bites in pregnant women and children

Summer is quickly approaching, which means mosquito season is beginning to ramp up here in the United States. In addition to the annoying itch after a bite, there are very real concerns in regard to different diseases mosquitoes can transmit. Here in the U.S., we have witnessed the transmission of West Nile virus every year since its introduction in 1999. West Nile virus can cause meningitis and encephalitis, and around 5 to 10 percent of those who develop severe disease will die from the infection. West Nile virus can affect people of all ages, with older adults being at the highest risk for severe disease and death. In addition to West Nile, there are other mosquito-borne diseases that are transmitted each year. Diseases can severely affect children, namely La Crosse encephalitis, eastern equine encephalitis and western equine encephalitis. Children are particularly vulnerable to mosquito bites since they spend more time outside and are more likely be exposed. Children also have to rely on an adult to provide and apply mosquito repellent.

We are no longer concerned only with local diseases that are being spread by mosquitoes. We are also extremely concerned about the possible emergence of the Zika virus. Over the past year, the Zika virus has rapidly spread throughout South and Central America, Mexico and the Caribbean. The rapid spread is directly related to human movement and travel. Mosquitoes can further spread the virus to others after feeding on an infected person. With the recent outbreak, we have discovered Zika is a very serious threat to pregnant women. If infected during pregnancy, the virus will invade the brain of the fetus, resulting in severe brain malformations (microcephaly) and even death. We have also learned the virus can be transmitted sexually, heightening concerns that women can be vulnerable to infection not just from mosquitoes, but also their partner. Since the majority of people infected will have no symptoms, a pregnant woman might not realize the risk if their partner is asymptomatic. If a pregnant woman or her partner lives in or plans to travel to an area where Zika is active, then mosquito bite prevention is critical.

Now that I have made the argument for the importance of protecting yourself and your children from mosquito bites, how best can that be accomplished? Of course, staying indoors 100 percent of the time can help reduce the risk of bites, but that is not realistic. Eliminating mosquito breeding grounds is an important step in helping reduce the mosquito population. Get rid of standing water and dump water out of any artificial containers around your house.

The best way to protect yourself when outdoors is to use mosquito repellent. A study recently published by Rodriguez et al. identified several repellents that were the most effective in preventing bites. As expected, repellents containing DEET performed the best. DEET is also recommended by the CDC; however, I have encountered many physicians who are hesitant to recommend a DEET-containing repellent for pregnant women and young children because they felt there wasn’t enough safety data in the literature. I have had no hesitation using DEET on myself or my children, particularly when traveling to Central America where I was concerned about dengue virus and chikungunya, and even here in Texas during the summer when I know we have West Nile virus-positive local mosquitoes. If you prefer something other than DEET, a natural alternative that was found to be as efficacious are those repellents contain oil of lemon eucalyptus. Once you have decided which one to use, keep in mind you will need to reapply the repellent every few hours to make sure you are continuously protected. Also, be careful when spraying to avoid getting it into the eyes, nose or airways.

Stay safe this summer, and don’t forget to pack your mosquito repellent along with your sunscreen when you head outdoors!

Reference:  Stacy D. Rodriguez, Lisa L. Drake, David P. Price, John I. Hammond, Immo A. Hansen.  The Efficacy of Some Commercially Available Insect Repellents for Aedes aegypti (Diptera: Culicidae) and Aedes albopictus (Diptera: Culicidae).  J. Insect Sci. (2015) 15(1): 140.