Malaria Chemoprophylaxis for Travellers
A 27-year-old soldier will deploy for three months to the southern border region of Saudi Arabia, working outdoors in intense sunlight. He takes fluoxetine for depression, which is well controlled, and has no other medical problems or drug allergies. He attends the travel clinic for advice on preventing malaria. Which of the following is the best chemoprophylaxis regimen?
- A.Doxycycline
- B.Mefloquine
- C.Chloroquine
- D.Atovaquone plus proguanilCorrect
Explanation
The Jazan and Aseer border areas are the only remaining focus of Plasmodium falciparum transmission in Saudi Arabia, and chloroquine resistant falciparum predominates across the region including neighbouring Yemen. Atovaquone plus proguanil is therefore the preferred regimen for this traveller: it is effective against chloroquine resistant falciparum, is taken daily beginning one to two days before travel, and is continued only seven days after leaving the area. Mefloquine is contraindicated in people with depression, anxiety, psychosis or seizure disorder because of its neuropsychiatric adverse effects, which removes it in this soldier. Doxycycline is an effective alternative but causes marked photosensitivity, a real problem for someone working outdoors all day, and it also requires four weeks of post travel dosing with attention to oesophagitis. Chloroquine is obsolete for this region because of widespread resistance. No chemoprophylaxis is fully protective, so personal protective measures remain essential: long sleeves, permethrin treated clothing and bed nets, and repellents containing DEET or picaridin. Any febrile illness during or up to a year after travel needs urgent blood films or rapid antigen testing. Primaquine and tafenoquine require documented normal glucose-6-phosphate dehydrogenase activity before use.
Why each option
- A.
- Doxycycline is effective but causes photosensitivity in a soldier working in intense sun and needs four weeks of continued dosing after departure.
- B.
- Mefloquine is contraindicated in depression and other psychiatric or seizure disorders because it can precipitate anxiety, psychosis and vivid neuropsychiatric reactions.
- C.
- Chloroquine is ineffective where resistant Plasmodium falciparum circulates, which includes the southwestern border region and the Horn of Africa.
- D.
- Correct. Atovaquone plus proguanil covers chloroquine resistant falciparum, avoids neuropsychiatric risk and lacks the photosensitivity that would trouble an outdoor worker.
Reference: CDC Yellow Book: Health Information for International Travel, Malaria Chapter, 2024. WHO Guidelines for Malaria, 2023.
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