The best way to avoid malaria is to avoid being bitten by a mosquito carrying the disease. In regions in which malaria is transmitted, this means avoiding mosquitoes which bite mainly in the evening/nighttime, covering up with clothing, using a bed net, using insecticides and insect repellents (DEET). There is lots of reliable information available, e.g., from the CDC.

Malaria preventatives are important for reducing malaria risk. Both the CDC and the WHO provide detailed information about malaria risk and drug resistance in different countries. There are several drugs used for malaria prevention, primarily: chloroquine, doxycycline, mefloquine, and atovaquoe/proguanil (malarone). Chloroquine resistance is widespread and mefloquine resistance is present in parts of Cambodia and Thailand. For each country, I determined if malaria was present and if it was resistant to chloroquine or mefloquine. Malarone is very expensive ($5.37/pill). Mefloquine would not be suitable for me, and there is also resistance in two of the countries I would be visiting. Chloroquine resistance is widespread. This leaves doxycycline, which costs only $0.1 per pill from Costco pharmacy. There are basically two Malaria exposure blocks in my trip: (1) India and SEA and (2) Africa and South America. Doxycycline needs to be taken 1-2 days before entry to a malarial region, daily while in the region, and for 28 days (4 weeks) after leaving the region. From this, it is straightforward to compute the number of days during which doxcycline is needed.

The main side effects of doxycycline are nausea and photosensitivity. The nausea can be reduced by taking it with food. Some 2% of people taking doxycycline develop severe photosensitivity (REF), but less severe photosensitivity is a common side effect. Doxycycline may also cause staining of adult teeth, especially if used in summer when presumabely there is significant sun exposure (Ayaslioglu E et al). I asked my doctor for a trial prescription; she said reactions appear within about five days, so I will try the medication for a week to test my reaction before getting the full year's worth of medication.

It is recommended to be tested for malaria exposure following a stay in a malarial region. I plan to get tested in Australia, where I may also restock on medications. This will be approximately my halfway point in the trip and a good chance to take care of any medical issues that may have arisen.

Ayaslioglu E et al 2005, Doxycycline-induced staining of permanent adult dentition, Australian Dental Journal, 50(4):273-5 doi:10.1111/j.1834-7819.2005.tb00373.x

Malaria self treatment

Based on my reading online, when traveling to areas where treatment may be delayed 24 hours, it may be necessary to self-treat for presumptive malaria. This should be done when having a high-fever in a malarial area and medical care and diagnosis should be sought as soon as possible. Do not take my word for it: I am not a doctor. See your doctor and visit some of the following web sites for competent information.

I am traveling in areas where there is resistance to Chloroquine and am already taking doxycycline for prophylaxis. Treatment needs to be done with drugs other than those being taken for prophylaxis. The best treatment for me would seem to be Atovaquone/proguanil (brand name Malarone. Atovaquone/proguanil is a drug combination administered as a single tablet of 250 mg atovaquone and 100 mg proguanil. The Canadian site listed below gives the treatment dosage as "1000 mg atovaquone AND 400 mg proguanil (4 tablets) once daily x 3 days". I should therefore carry at least 12 tablets of Malarone. I am currently in Chang Mai in Thailand where there is the Malaria Centre; I will contact them and see if they offer or can recommend a reliable place to get Atovaquone/proguanil.

http://www.phac-aspc.gc.ca/publicat/ccdr-rmtc/04vol30/30s1/page6_e.html
Canadian Recommendations for the Prevention and Treatment of Malaria Among International Travellers

http://wwwn.cdc.gov/travel/contentMalariaDrugsPublic.aspx
Information for the Public: Prescription Drugs for Malaria

WHO malaria drug resistance
http://www.who.int/drugresistance/malaria/en/index.html

CDC FAQ on Malaria
http://www.cdc.gov/malaria/faq.htm#4

Self-treatment for malaria: the evidence and methodological issues.
Health Policy Plan. 2002 Dec;17(4):333-44.
McCombie SC.
http://www.ncbi.nlm.nih.gov/pubmed/12424205

Getting Ready: Malaria
http://www.drwisetravel.com/malaria.html

Permethrin bed net treament protocol
Schreck, CE and Self, LS, Bed Nets that Kill Mosquitos, World Health Forum, 1985:6 p342-4.
http://whqlibdoc.who.int/whf/1985/vol6-no4/WHF_1985_6(4)_p342-344.pdf