Health Topic: Travel Medicine

by Dr. Wilbur Kuo, MD
March 29, 2016


Today's topic: Malaria Prevention

- Malaria is a parasite transmitted by mosquitoes
- It causes fever, headache, nausea, abdominal pain, diarrhea, vomiting, malaise
- This progresses to anemia and spleen enlargement
- And eventually to blood clots in multiple organs leading to multi-organ failure
- There were 1700 cases in the United States in 2012
- Cdc.gov/malaria has a map of where malaria can occur. It is predominately in Africa, south of the Sahara, and parts of Oceania, such as Papau New Guinea
- Relapses can occur many months after travel and you should always let your doctor know of any foreign travel in the past year before you became ill

Malaria prevention:non-medication methods
- pregnant women should avoid travel to malaria areas
- Avoid outdoor exposure between dusk and dawn when the mosquitoes are feeding
- Wear clothing that reduces the amount of exposed skin
- Wear insect repellant: DEET 30-50% or picardin
- Sleep within bed nets treated with insecticide such as permethrin
- Treat clothing with permethrin, sold in outdoor stores as permanone repellent
- Stay in well-screened or air-conditioned room

Malaria prevention: medications
- should be combined with mosquito bite prevention
- Choice of medication depends on location of travel, type of malaria present, and local drug resistance patterns. Cdc.gov/travel has up to date recommendations based on travel itinerary
- For example, travelers to Mexico and Central America are more likely to encounter P. vivax and travelers to Thailand, Cambodia, Laos, and Vietnam are more likely to encounter multi-drug resistant P. Falciparum
- Most malaria meds have to be started before travel and continued for some after travel to ensure that the parasite in all its forms is killed whether hiding in the liver or in the red blood cells

Common malaria prevention medications
Malarone
- Started 2 d prior to travel and continued until 1 week after return
- Taken daily
- Can cause gi upset
- Can't be given if pregnant or kidney problems
Mefloquine
- Taken once a week
- Start 2 weeks prior to travel and continue until 4 weeks after travel
- Some people get gi upset or strange dreams
- 5% will get anxiety or depression
- Can't be taken if seizure history or heart conduction problems
- Can be taken while pregnant
Doxycycline
- Start 2 d prior to travel and continue for 4 weeks after
- Taken once daily
- Can cause gi upset, sun sensitivity
Chloroquine
- taken once weekly
- Start one week prior to travel and continue for 4 weeks after travel

For more information check out cdc.gov/malaria
As always, consult your physician prior to making any diagnoses or changing your treatment decisions.