Malaria is spread by night-biting mosquitoes, so bite avoidance is the first defence: use insect repellent on exposed skin, sleep under an insecticide-treated net, cover up after dusk, and stay in screened or air-conditioned rooms where possible.
For many destinations a doctor or travel clinic will prescribe antimalarial medication. The right choice depends on the country, drug resistance patterns, your medical history, pregnancy, and how long you are staying. These medicines must be started before you arrive and continued for a set period after you leave, so plan a travel-health appointment several weeks ahead.
No prevention is fully foolproof. Seek urgent medical care if you develop fever, chills, headache, or flu-like symptoms during travel or for up to a year after returning from a malaria area, and tell the clinician where you travelled. Untreated malaria can become life-threatening quickly.