Wormwood, artemesium absinthium`s anti parasitic properties, have been known since ancient Greek times, and are even mentioned in the Bible.  It is today used in Nigeria to kill the mosquito parasite in humans. Wormwood has no side effects, and its availabitlity in capsule form of the dried leaves or in a liquid extract form makes it easy and safe to take for those who dont wish to ingest synthetic chemicals. If I were a flight crew traversing the tropics I would take it before during and after each trip. I regularly take my extract on my Thailand holidays. Maybe your doctor hasnt mentioned this`, (they dont like the word  ^àlternative`),  but keep in mind thait took mainstream medicine 400 years to accept the natural cure for scurvy, that was Vitamin C, even though this one has been around a bit longer!.