Margaret Stroz, MD
Medical Director, The Occupational Health Center at Chester County Hospital
Mosquitoes, ranked as the World’s Deadliest Animal by Newsweek in 2015, account for nearly one million deaths per year according to the Centers for Disease Control and Prevention and the World Health Organization. With the exception of the recent Zika Virus health crisis, few people in North America generally concern themselves with these facts. Travelers, however, may think otherwise.
As identifying specific risks related to a traveler's itinerary, OHC's pre-travel consultation allows you to best prepare for disease-free travel with vaccinations, medications and good advice. One thing that is clear from my numerous discussions with travelers is that many travelers are visiting tropical climates where mosquitoes reign, carrying with them an increased risk of a multitude of diseases from African Trypanosomiasis to Zika.
We believe that an educated and informed traveler is a safe traveler. In addition to our recommendations for vaccines and preventative medications, we provide advice for travelers' personal protective measures to avoid mosquito bites. Preventing mosquito bites is your best defense to ward off diseases these pests carry and transmit. In our local region, mosquitoes are primarily just that, a pest, leaving a local histamine response, or itchy area. But for travelers, the consequence is potentially much more severe.
Due to the seriousness of diseases encountered while traveling in tropical areas with mosquitoes, the CDC recommends the use of repellents containing DEET at 30-35% concentration or Picaridin at >20%. Many individuals prefer the more pleasant odor of the Picaridin products such as Cutter or Natrapel. Others prefer to use natural botanicals such as eucalyptus, citronella or geranium oil, with the assumption that they are safer than the noted EPA products. However, there is insufficient data regarding their safety, duration and effectiveness to recommend their use as viable alternatives when travelling in the tropics. Whereas DEET and Picaridin products, when applied as directed, have not shown significant toxicity for over 30 years of their use. In fact, both are safe in children as young as 2 month of age.
To maximize safe and effective use of repellents, remember this commonsense and not–so-obvious guidance:
- Limit the use of repellents by wearing light weight clothing to cover as much skin as possible.
- Don’t apply repellent underneath clothing.
- Avoid contact in the eyes, mouth or on open skin. To limit inhalation of repellents, use a lotion preparation.
- Wash your hands prior to eating to remove residual repellent.
- In children, avoid applying to portions of the child’s hands that are likely to have contact with eyes or mouth. Never allow a young child to apply their own repellents. Never use in children under 2 months of age.
- Although there is no evidence that repellents pose a hazard to unborn babies or children who are breastfeeding, pregnant and breastfeeding women should minimize use.
- Remember, the risk of disease to a pregnant female or her unborn child may pose greater harm than a potential risk of exposure to repellent.
- When applying both sun screen and repellent; apply sun screen first. The outer layer should be the repellent. Caution, both products may need more frequent reapplication.
- Reapply repellent if mosquito bites occur. Concentration reflect the duration of effectiveness, with lower concentrations requiring more frequent reapplication.
- Knowledge of mosquitoes breeds and the disease they transmit will effect times for diligent application of repellents. Malaria is transmitted by the Anonpheles mosquito, and Japanese Encephalitis by Culex mosquito, both of which bite from dusk to dawn, whereas the majority of viral diseases, including Yellow Fever, Dengue, Chikungunya, and Zika are transmitted by Aedes mosquitoes, which bite during daylight hours, particularly early morning and late afternoon. Application of insect repellents at greatest risk times is important. Remember if Malaria is the concern, think repellents after dark, if it’s Zika to be avoided, then daytime repellents are key.
- Consider pre-travel treatment of clothing with Permethrin, an insecticide licensed for clothing only which when applied correctly can be effective for several months.
- Remember to use repellents according to the label directions.
Reach Out To Chester County Hospital BEFORE You Travel
The health professionals at The Travel Medicine Program at Chester County Hospital can help you prepare for travel. To schedule an appointment for a travel-related health assessment and necessary immunizations and medications, click here.