DEET

Obviously, the most effective antimalarial is avoiding the female Anopheles mosquito bite that causes the disease in the first place. The best way to dodge this dusk-to-dawn pest is still through use of repellents containing DEET, scientifically known as N, N-diethyl-m-toluamide. The chemical’s been around since the ’40s, when the Agriculture Department developed it. Though DEET occasionally causes allergic reactions, EPA studies have concluded that it is not carcinogenic.

Surprisingly, the term “repellent” is a misnomer: DEET actually works by confusing mosquitoes, not repelling them. The chemical clogs receptors in mosquitoes’ mouths and eyes that can normally detect your body’s carbon dioxide excretions from as far away as 70'. After a good whiff, the inebriated pest finds herself unable to sort out all the cacophonous signals her brain is receiving. It may take several hours to cure her hangover.

Some people report that natural repellents or Avon’s “Skin So Soft” work for them. You may have had success with these at home. But unless they’ve proved successful for you in the tropics, it’s wise to carry DEET just in case — from Outside and other sources.