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Malaria is an arthropod-borne parasitic infection caused by Plasmodium species and remains endemic in sub-Saharan Africa, parts of South and Southeast Asia, Oceania, and Central and South America. In the United States, malaria occurs almost exclusively in travelers returning from endemic regions, with approximately 2000 cases reported annually between 2007 and 2022. The disease is transmitted through the bite of an infected Anopheles mosquito. Pretravel evaluation is essential for individuals planning travel to malaria-endemic areas. Clinicians should review the traveler’s medical history, current medications, pregnancy status, allergies, itinerary, and duration of travel. Selection of an appropriate chemoprophylaxis regimen should also consider regional Plasmodium species, resistance patterns, and transmission intensity. Commonly used prophylactic agents include atovaquone–proguanil, doxycycline, mefloquine, chloroquine, primaquine, and tafenoquine. In addition to chemoprophylaxis, travelers should be counseled on mosquito-bite prevention measures, including wearing protective clothing, using DEET-containing repellents, sleeping under permethrin-treated bed nets, and avoiding outdoor exposure during peak mosquito activity. Effective malaria prevention depends on appropriate medication selection, patient adherence, and coordinated care among healthcare professionals. This activity reviews the evaluation and management of malaria chemoprophylaxis and highlights key strategies for risk assessment, prevention counseling, and medication selection. This activity also emphasizes the role of the interprofessional healthcare team in improving outcomes for travelers who may be exposed to this potentially life-threatening infection. Objectives: Identify travelers at risk for malaria based on destination, duration of travel, and planned activities in endemic regions. Select appropriate chemoprophylaxis based on patient-specific factors, travel itinerary, and current evidence-based guidelines. Implement effective counseling strategies to promote mosquito-bite prevention, including the use of repellents, protective clothing, and bed nets. Collaborate with interprofessional healthcare providers to ensure safe medication selection, provide effective patient education, and reduce the risk of travel-associated malaria. Access free multiple choice questions on this topic.

Malaria is a parasitic infection caused by six species of Plasmodium and is one of the leading causes of fever in returning travelers. The species that cause disease in humans are Plasmodium falciparum, P vivax, P ovale curtisi, P ovale wallikeri, P malariae, and P knowlesi. The protozoa are transmitted to humans through the bite of an infected Anopheles mosquito, which is most active during the early morning and evening hours. (see Image. Anopheles Species Mosquito). After transmission, Plasmodium sporozoites infect hepatocytes and multiply within the liver, where they mature into schizonts. The schizonts are then released from liver cells, where they infect red blood cells and continue to multiply. Clinical disease results from the release of Plasmodium merozoites during the rupture of infected erythrocytes (see Image. Plasmodium falciparum Ring Stage in Erythrocytes). P vivax and P ovale can persist in the liver as dormant hypnozoites, which may reactivate and cause infection weeks to years after the initial exposure.[1][2] Malaria is endemic to sub-Saharan Africa, Central and South America, South and Southeast Asia, Oceania, and focal regions of the Middle East. In the United States, cases occur almost exclusively among travelers returning from these regions. Approximately 2000 cases were reported annually between 2007 and 2022. In the European Union, about 8000 cases were reported each year between 2018 and 2019. Travelers to endemic areas should therefore receive counseling on malaria risk in geographic areas, mosquito-bite prevention, and appropriate chemoprophylaxis (Centers for Disease Control and Prevention [CDC]; Data and Statistics on Malaria in the United States).

Healthcare professionals, including primary care clinicians and advanced practice nurses, should be familiar with malaria prophylaxis. The interprofessional healthcare team should provide accessible, culturally appropriate guidance for travelers, particularly those visiting friends and relatives in malaria-endemic areas. Clinicians should assess travel-related risks and encourage both mosquito-bite prevention and the use of chemoprophylaxis when indicated. Using a health belief model to identify potential barriers to chemoprophylaxis adherence and to explore acceptable alternatives may improve counseling outcomes. In addition to prescribing prophylaxis, clinicians must educate travelers on strategies to avoid mosquito bites. Nurses should ask patients about recent or planned travel to endemic regions and initiate appropriate steps for malaria prevention in collaboration with the clinician. Pharmacists play an important role by reviewing medication selection, verifying dosing, and counseling patients about potential adverse effects and drug–drug interactions. Clinicians should also use these encounters to assess risk for the entire traveling party and encourage all travelers to seek a pretravel consultation. Preventive education should emphasize practical measures such as wearing protective clothing, applying a DEET-containing insect repellent, using mosquito nets while sleeping, and limiting outdoor exposure after dusk during peak mosquito activity. Effective malaria prevention requires coordinated efforts across the interprofessional healthcare team.

Missed Dosing of Chemoprophylaxis CDC guidance for missed doses varies by medication. In general, travelers who miss a dose of a once-weekly prophylactic medication should take the dose as soon as they remember and then resume the regular weekly schedule. If the dose is missed by more than 2 days, drug levels may fall below protective levels. The missed dose should be taken as soon as possible, followed by the next dose 7 days later, then weekly thereafter. For daily dosing regimens, the medication should be taken at the same time each day. If a dose is missed by 1 to 2 days, protective drug levels may be reduced. The missed dose should be taken as soon as it is remembered, and subsequent doses should continue daily at the usual time.

Clinicians should consider monitoring the INR in patients taking atovaquone–proguanil with warfarin. Creatinine clearance should be assessed before prescribing doxycycline, and patients should be screened for G6PD deficiency before initiating primaquine or tafenoquine for malaria prophylaxis.