**2. Education**

Before travel, counseling the individual on the specific risks in the areas they may be visiting is an essential part of trip preparation. When counseling the traveler prior to visiting an endemic area, they must be made aware of the route of transmission of malaria, associated symptoms, variable incubation periods prior to symptom onset, when to seek medical aid, and the risks of contracting the disease, including death, especially in high-risk populations. They need to be aware that recent immigrants to non-malaria endemic areas returning to their home of origin to visit friends and relatives (VFR's) are at high risk for contracting malaria as acquired immunity is not long lasting (Centers for Disease Control and Prevention, 2012). Travelers should be counseled on proper personal protective measures including mosquito bite avoidance, especially during the peak transmission periods of evening and nighttime hours, mechanical and chemical barrier protection, vector control, and the appropriate use and importance of chemoprophylaxis.

Malaria can be effectively treated if suspected and recognized early and appropriate medical intervention is made within a timely manner. Time to symptom onset from initial exposure can vary, ranging as early as 7 days following a mosquito bite to several months or greater following departure from an endemic region. The diagnosis of malaria is a medical emergency since time to definitive treatment is a critical factor in determining clinical outcome. For these reasons, travelers should be counseled to seek medical care as soon as possible if they have any symptoms that may be related to malaria. The clinical presentation of malaria consists of a nonspecific, flu-like illness manifested by fever, chills, malaise, anorexia and headache. In cases of severe illness, altered mental status, seizures, respiratory disease (ARDS) and coma may be present (CDC, 2012).

Availability of medical care while traveling should be explored prior to travel. There may be rare instances where the chemoprophylaxis regimen is suboptimal or the traveler does not agree to medically advised chemoprophylaxis. In cases when the traveler develops clinical symptoms consistent with malaria and does not have timely access to medical care and definitive parasitological diagnosis, presumptive, self-administered therapy may be considered (WHO, 2010; CDC, 2012). When prescribing presumptive self-treatment, the CDC recommends a consecutive 3-day course of either atovaquone-proquanil or artemetherlumefantrine. One should never use the same drug for treatment that had been prescribed for prophylaxis. It should be stressed to the traveler that even though presumptive treatment may be available, they should seek medical care as soon as possible.

#### **3. Personal protective measures**

Several measures can be taken by the traveler while in endemic areas to reduce the risk of mosquito bites, thus reducing the risk of contracting malaria. The *Anopheles* mosquito only feeds at night, making the hours between dusk and dawn those that the traveler must be most vigilant for vector avoidance and mosquito control measures. Staying indoors, sleeping in screened-structures, and using mosquito nets during peak feeding times are all effective and relatively simple ways to reduce transmission of malaria. Other protective measures including clothing that minimizes exposed skin, eliminating mosquito breeding sites, and using appropriate repellents/insecticides on skin and clothing, should be discussed with the traveler as well (Chen et al., 2006; CDC, 2012).

A systematic literature review concluded that environmental management programs were highly effective at reducing the morbidity and mortality associated with malaria, and if educated properly travelers can reduce their risk significantly through these personal and environmental protective measures (Keiser et al., 2005).

Insecticides such as permethrin can be used as a spray to kill mosquitoes on contact, or can be used to impregnate clothes and mosquito nets for long-term protection. A 2003 randomized-controlled trial in sub-Saharan Africa showed a reduction in all-cause child mortality by 15-33% with the use of permethrin treated bed nets and curtains, and a 1995 study of permethrin impregnated uniforms in Columbian soldiers showed a decrease in incidence of malaria from 14% to 3% (Phillips-Howard & Nahlen et al., 2003; Soto & Medina et al., 1995), indicating mosquito avoidance and control measures can be highly effective in preventing malaria transmission.

Repellents prevent arthropod bites via alterations to sensorial organs. There are several different commercially available repellents including DEET (*N*,*N*-diethly-3-methylbenzamide), picaridin (2-(2-hydroxyethyl)-1-piperidinecarboxylic acid 1-methylpropyl ester), oil of lemon eucalyptus (*para*-menthane-3,8-diol), and IR3535 (3-[*N*-butyl-*N*-acetyl] aminopropionic acid, ethyl ester). The efficacy and duration of repellents vary considerably among products and species of mosquito (Zielinski-Gutierrez et al., 2012). Several studies have suggested DEET and picaridin to be the most efficacious and long lasting (Fradin & Day, 2002; Trigg, 1996; Govere et al., 2000; Badolo et al., 2004). Both DEET and picaridin demonstrate efficacy between five and seven hours after application, with variations in efficacy and duration of effectiveness related to repellent concentration, humidity, temperature, perspiration, exposure to water, and abrasion (Zielinski-Gutierrez et al., 2012). There seems to be a ceiling effect with DEET at concentrations above 50%, where higher concentrations do not offer additional benefit.

DEET, at concentrations up to 50%, can be used on children over two months of age. Children less than two months should be protected with a child carrier covered with a mosquito net. Beyond labeled precautions, the U.S. Environmental Protection Agency (EPA) and CDC do not recommend additional warnings for repellents in children > 2 months, pregnant or lactating women (Zielinski-Gutierrez et al., 2012). Like physical barriers, repellents and insecticides are only effective if used properly and consistently, thus ensuring the traveler is aware of proper use before departing is an essential part of pre-trip counseling.
