The new treatment for malaria

Southeast Asia -- particularly Laos and Cambodia is renowned for harboring resistant strains of malaria, the deadly mosquito born disease. Malaria carrying mosquitoes bite in the evening and at at night. Wearing long sleeved shirts, pants, and staying in sealed air conditioned bedrooms -- or using a chemically treated mosquito net -- goes a long way toward preventing the bites that cause malaria (or dengue fever, a common mosquito-born disease for which there is no drug treatment).

The world breathed a sigh of relief when artemisinin -- a Chinese and Southeast Asian herbal treatment for malaria -- was rediscovered by modern scientists. Artemisinin Project explains the trajectory of this ancient therapy to its modern pharmaceutical application:
The World Health Organization (WHO) and other development agencies first endorsed artemisinin-based therapies for the treatment of malaria in 2004. The WHO 2005 recommendations for first-line malaria treatment include several ACTs - in fact, all six recommended therapies include artemisinin derivatives.
Recently fears have arrisen that this brilliant new malaria drug might soon become ineffective, as in Southeast Asia some mosquitoes have shown resistance to the drug. This concern prompted the World Health Organization's director-general to tell drug companies they must not market the drugs made from the Chinese plant artemisinin except in combination with other, older malaria drugs. The biggest manufactures of the drug were quick to comply with the demand, but some doctors assert that certain patients require artemisinin monotherapy.

A 2006 study on traveler experiences Artemisinin therapies advises:
Artemisinin derivatives, such as artesunate, artemether and dihydroartemisinin, are the most parasiticidal of all the antimalarial drugs against Plasmodium falciparum . . . However, several challenges remain, including the limited availability of GMP quality drugs, the emergence of fake drugs, and their optimal deployment in malaria-endemic countries. . . . Artemisinin-based drugs are easily available in several malaria-endemic countries and are sold as mono- or combination therapies. They are manufactured in several countries, packaged differently and contain package inserts of varying quality and accuracy. WHO currently recommends malaria-endemic countries to use three days of an artemisinin-based combination treatment (ACT) e.g. artemether/lumefantrine (A/L), artesunate (4 mg/kg/day) plus an effective, longer acting partner drug, such as amodiaquine or mefloquine [3]. If used alone, seven days of treatment of an artemisinin derivative is necessary because shorter courses result in unacceptably high rates of recrudescence. . .

Travellers should be aware that artemether/lumefantrine is known as Riamet® in temperate countries and CoArtem® in malaria-endemic countries. Adult Riamet® contains 24 tablets (six dose regimen) but adult CoArtem® contains only 16 tablets (4 dose regimen).
Let's say you get malaria on your trip to Southeast Asia. Unless you came prepared -- or get yourself to a Bangkok hospital quickly -- the anti-malarial medication for sale at the local hospital in Laos or Burma could well be fake. I blogged about fake drugs here.

Because of the fake drug problem, if you are traveling in an infested area, consider getting a prescription for the treatment before you go. Another option is to start taking preventative drugs prior to your entry into a malarial region.*

For country-by-country information about diseases, including malaria, and appropriate medications, I recommend Britain's NaTHNaC (National Travel Health Network and Center) sponsored by the Foreign and Commonwealth Office. The website is excellent.

Generally speaking, unless you are going off the beat-and-track sensible clothing, air conditioned or (at least) well-sealed sleeping quarters, and some applications of mosquito repellent is likely to prove sufficient precaution against malaria. These precautions are necessary anyway, to protect you against dengue fever, for which there is no drug treatment.*

What else? Well, in my opinion mosquito coils are not a good idea. Certain natural alternatives to Deet stack up well -- at least in the laboratory.
-Artemisinin Project
- Welcome Trust has the story behind the (re)discovery of the drug.
* Modern drugs used preventively against malaria include mefloquine (Lariam®), doxycycline (available generically), and the combination of atovaquone and proguanil hydrochloride (Malarone®). Lariam ® is the subject of great controversy: "Scores of Peace Corps volunteers are coming forward saying that over the past 12 years they suffered crippling paranoia, anxiety, hallucinations, memory loss, suicidal behavior and physical ailments from seizures to vision difficulty because of the drug handed out by government doctors to prevent malaria," reported UPI in 2002. Malarone ® is a new drug which happens to be quite expensive but I have not found any reports indicating it to be especially unsafe. Doxycycline is safe for most people and cheap.
** In recent years, there have been cases of dengue in every Southeast Asian city, including Singapore. Dengue, like malaria, can be fatal. In Thailand alone, 60000 cases of dengue and 29 deaths were reported in 2007.

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