Friday, July 31, 2009

Malaria in Bolivia

Travel websites warn tourists to "consider taking medication for malaria prophylaxis (cholorquine, doxycycline, or mefloquine)," particularly in the areas "surrounding Santa Cruz," where "yellow fever and malaria are two common mosquito-borne diseases" (MDTravel). The CDC indicates that "areas of Bolivia with Malaria" include "all areas <2,500 m" in the regions of "Beni, Chuquisaca, Cochabamba, La Paz, Pando, Santa Cruz, and Tarija." However, the CDC also warns that Chloroquine, commonly used to prevent and treat malaria, "is NOT an effective anti-malaria drug in Bolivia and should not be taken to prevent malaria in this region" (CDC). In reality, "none of the currently available prophylactic medications is 100% effective. If travel to malarious areas is unavoidable, insect protection measures must be strictly followed at all times" (MDTravel).

Furthermore, areas above 2,500 meters are not absent of the disease. "Malaria cases have been reported on the Bolivian high plateau, confirming scientists' predictions that mosquitoes have adapted to a colder climate." These cases "were found in Oruro, western Bolivia, around 3,710 metres above sea level". Researchers have "demonstrated that some anopheles mosquitoes" (the ones that carry malaria) "have adapted to living at altitudes between 2,520 and 3,590 metres--conditions very different from their usual environment: warm, tropical and subtropical regions below 2,600 metres." Some researchers postulate that "a new subspecies has emerged." Scientists have noticed that the tails "have become shorter" and the "mosquito can live in dirty water rather than the clean water it inhabits at lower levels. It can survive" nighttime temperatures "as low as eight degrees Celsius" (Pabon) This can be terrifying news for the residents of these high-altitude regions since many do not have access to adequate health care to combat malaria.

One case study, examines the village of Tuntunani, which is "situated at an elevation of 2,300 meters." This community "experienced its first malaria outbreak in 1998". "An investigation two years later indicated that the epidemic resulted from introduced transmission...58% of the people had been ill for three weeks or longer" as a result. "This outbreak demonstrates the vulnerability of highland populations with poor access to health care to introduced malaria" (Rutar 15).

It seems that malaria is spreading in a country where its effects are already devastating. "Malaria affects over 3.5 million people in Bolivia each year. The Amazon basin regions of Beni and Pando have the country's highest infection rates. In these regions, migratory worker populations, such as castaneros" (Brazil nut farmers) "run a high risk of malaria infection"
When these harvesters "are sick with malaria, the family income drops since workers do not earn their wages and family members stay home to care for them." Estimates indicate that "at least 15,000 families from rural areas depend on this market for survival" (USAID). USAid led a pilot study among the community of Brazil nut harvesters and found that one-third of the farmers tested positive for malaria.

Pregnant women in Bolivia are also at high risk for the disease. Malaria affects pregnant women and children drastically. The anemia and fever from malaria can cause birth defects and death. Furthermore, there is no approved treatment or avoidance measures for pregnant women to take in Bolivia. Many of the prophylactic medications that work against the Bolivian strain of malaria can cause birth defects or miscarriages during the first trimester. At this time, most women find that they can only use mosquito repellent and mosquito nets to avoid contracting malaria during pregnancy.

Map of regions in Bolivia where malaria is endemic

Pabon, Cristina. Malaria spreading on Bolivian High Plains. SciDevNet.
Rutar, Tina. Eduardo J Baldomar Salgueiro, James H Maguire. "Introduced Plasmodium Vivas Malaria in a Bolivian Community at an Elevation of 2,300 Meters."
TravelMD. Bolivia.
USAID Reducing Malaria in Migrant Populations

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