Travel to tropical climates entails contact with a variety of insects capable of transmitting diseases.
The mosquito is the best known culprit and may transmit malaria, yellow fever, dengue fever, and Japanese encephalitis.
Ticks, flies, fleas, and other bugs and transmit debilitating and deadly illnesses.
There are specific prevention strategies for malaria (medical prophylaxis), yellow fever and Japanese encephalitis (vaccination), but the majority of insect-borne disease prevention relies on avoiding insect bites altogether.
There are three main ways for individuals to protect themselves from the hungry hordes.
A. Know your insects--learn about the peak biting times and locations, their different geographic and seasonal distributions.
B. Try to arrange accommodations that are well screened, air-conditioned, or have bed nets in good condition.
C. When at the beach, lie on a lounge or at least a blanket or a long towel. Do not lay clothing on the ground or shake them vigorously before re-dressing if you do.
D. In the tropics and subtropics avoid swimming or wading in fresh water and hiking around stagnant ponds and marshes. If fresh water contact occurs, towel dry immediately.
A. Clothing - wear long sleeved shirts tucked into pants, and pants tucked into socks or boots. Avoid dark or brightly colored clothing and jewelry. Wear shoes that provide maximum coverage. Avoid sandals. Don't go barefoot.
B. Eliminate Fragrance - use unscented hair and hygiene products. Avoid perfumes and aftershave.
C. Bed nets - when accommodations are not adequately screened or air-conditioned bed nets are essential for comfort and protection. Nets should be treated with permethrin and regularly checked for tears and holes. They should be tucked under the mattress. Treated nets provide some protection even if torn or your skin is against the net.
Double the protection to reduce the risk of bites and disease. Insect repellents produce an effect that causes them not to bite, whereas insecticides act primarily by killing on contact. Some chemicals have both effects.
A. Repellents -
The two repellents with the highest degree of effectiveness approved for use on the skin are DEET and Picaridin. Typically the higher the concentration the longer the duration of protection. However, with DEET the effectiveness plateaus at about 50%. Because there are variables such as sweating, abrasion from clothing, weather, etc. the duration listed on the label should only be used as a guide and repellent reapplied when biting activity is noticed.
There is a delayed release formulation of 20% DEET which can provide protection up to twelve hours at a lower risk of systemic absorption and local reactions.
Picardin is considered equal to DEET in effectiveness, can be less irritating and won't damage synthetics or plastics, and is now sold in the U.S. in adequate concentrations.
Do not use combined sunscreen and insect repellent products. If both are needed apply the sunscreen first. Be aware this may decrease the efficacy of the sunscreen by about a third.