What are the recommended malaria prevention measures for travelers to Madagascar?

Malaria Prevention for Travelers to Madagascar

Chemoprophylaxis Selection

Travelers to Madagascar should use atovaquone-proguanil, doxycycline, or mefloquine as first-line chemoprophylaxis, as Madagascar has chloroquine-resistant P. falciparum malaria. 1

First-Line Options for Chloroquine-Resistant Areas

The CDC recommends choosing from three equally effective first-line agents based on individual patient factors: 1

• Atovaquone-proguanil: Start 1-2 days before travel, continue daily during travel, and for only 7 days after departure—the shortest post-exposure duration of any regimen 1

• Doxycycline 100 mg daily: Start 1-2 days before travel, continue daily during travel, and for 4 weeks after departure 1, 2

  • Contraindicated in pregnancy and children <8 years 1
  • Patients must avoid excessive sun exposure due to photosensitivity risk 2
  • Take with liberal fluids to prevent esophageal irritation 2

• Mefloquine 250 mg weekly: Start 1-2 weeks before travel, continue weekly during travel, and for 4 weeks after departure 1

  • Avoid in patients with seizure history, psychiatric disorders, or those requiring precision movements 1
  • Neuropsychiatric side effects occur in 70% of cases during the first three doses; discontinue immediately if severe mood changes, hallucinations, or seizures develop 1

Special Populations

• Pregnant women: Use chloroquine as the safest option and carry Fansidar for presumptive self-treatment if fever develops and medical care is unavailable 1

• Children <15 kg: Use chloroquine; mefloquine and doxycycline are contraindicated 1

Critical Timing Requirements

Never stop prophylaxis early—continue for the full 4 weeks post-exposure (except atovaquone-proguanil at 7 days) even if feeling well, as symptoms can develop weeks to months after leaving Madagascar 1, 3

Personal Protection Measures Against Mosquito Bites

Combine chemoprophylaxis with rigorous mosquito avoidance measures, as no antimalarial regimen guarantees complete protection. 3

DEET-Based Repellents (First-Line)

• Apply DEET at 20-50% concentration to exposed skin—this provides optimal protection in malaria-endemic areas 3
• Higher concentrations (up to 50%) provide longer protection time and should be considered first choice 3

Critical DEET application guidelines to minimize toxicity risk: 4, 3

• Apply sparingly only to exposed skin or clothing
• Avoid high-concentration products on children's skin
• Do not apply to children's hands (risk of eye/mouth contact)
• Never use on wounds or irritated skin
• Wash treated skin after coming indoors
• Do not inhale, ingest, or get into eyes

Behavioral and Barrier Measures

• Remain in well-screened areas during evening and nighttime hours when Anopheles mosquitoes feed most actively 3
• Sleep under permethrin-impregnated mosquito nets 3
• Wear long-sleeved clothing and long trousers after sunset 3
• Apply permethrin (Permanone) spray to clothing for additional protection 3
• Use pyrethroid-containing flying-insect spray in living and sleeping areas during evening and nighttime hours 4

Prevention of Relapsing Malaria

For travelers with prolonged exposure in Madagascar (e.g., missionaries, Peace Corps volunteers), consider primaquine 30 mg base daily during the last 2 weeks of the 4-week post-exposure prophylaxis period to prevent relapses of P. vivax and P. ovale. 1

• Mandatory G6PD testing is required before primaquine use 1
• Contraindicated in pregnancy 1

Critical Warnings

• Any fever or influenza-like symptoms during or after travel to Madagascar requires immediate medical evaluation with thick and thin malaria smears 3
• Symptoms can develop as early as 8 days after initial exposure or as late as several months after leaving Madagascar, even after chemoprophylaxis has been discontinued 3
• No antimalarial regimen guarantees complete protection, and malaria can still be contracted despite perfect adherence to all preventive measures 3
• Doxycycline provides substantial but not complete suppression of P. falciparum asexual blood stages and does not suppress sexual stage gametocytes—treated individuals may still transmit infection to mosquitoes 2