Haitian Child

Haitian Child

Monday, December 3, 2012

Elephantiasis in Haiti

Lymphatic filariasis is a mosquito-spread worm infection that is present in 80% of the regions of the country, which really means in every region of the country.


Microfilaria of Wuchereria bancrofti. Photo courtesy CDC.

There are five stages in the life cycle of the worm. Mosquitoes ingest the first stage or microfilariae and the second and third stages develop in the mosquito. Third stage larvae are inoculated into humans for the final two stages. The larvae take about a year to mature to the fifth stage worm. The worms invade the lymphatic system and the symptoms of elephantiasis are due to blockade of lymph flow, which leads to permanent swelling of an arm or leg, or of the scrotum in men. Female worms are about 3 to 4 inches long and the males are half that size. Elephantiasis is the common name for the affliction, and describes the gross deformity of the affected region of the body. Filariasis is rarely fatal, but the gross deformities that result are such that the World Health Organization (WHO) identified the disease as the second leading cause of permanent and long-term disability in the world, after leprosy.
  
Haitian mother with elephantiasis. Photo courtesy New York Times. 

The most common symptoms of an acute infestation are fever, increase in the size of the lymph nodes (groin, axilla, elbow), scrotal pain, limb or genital swelling, and skin exfoliation. The urine can turn "milky" if fatty lymph fluid is present. The swollen skin is susceptible to secondary infection with a fungus or bacteria.  

Albendazole and diethylcarbamazine (DEC) kill the larval form, which if not treated, will mature in about a year to a worm that cannot be killed. 

Studies have shown that if an entire population takes the drug once a year, and every year, for a sufficient number of years, the amount of parasite circulating in humans and mosquitoes will fall low enough to eradicate the infection. One estimate is that 70% of the population needs to take a medication once each year for eight consecutive years.

A Center for Disease Control (CDC) survey recently reported that 8.7 million Haitians (over 80% of the population) received one dose of medication by two years after the earthquake. If that successful effort can be sustained for seven more years, there is hope to eradicate filariasis in Haiti!

However, "every mouth counts." Providers must not presume an individual takes the medication. For success (compliance), providers have learned that they must be present when an individual swallows the medication.

Salt fortified with DEC has been used to widen coverage. This strategy was invented by Frank Hawking, the father of Stephen Hawking, and was used in a filariasis-eradication campaign in China in the 1980's.

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