SleepingSickness

African trypanosomiasis or sleeping sickness[1] is a parasitic disease of humans and other animals. It is caused by protozoa of the species Trypanosoma brucei.[2] There are two types that infect humans, Trypanosoma brucei gambiense (T.b.g) and Trypanosoma brucei rhodesiense (T.b.r.).[1] T.b.g causes over 98% of reported cases.[1] Both are usually transmitted by the bite of an infected tsetse fly and are most common in rural areas.[1]

Initially, in the first stage of the disease, there are fevers, headaches, itchiness, and joint pains.[1] This begins one to three weeks after the bite.[3] Weeks to months later the second stage begins with confusion, poor coordination, numbness and trouble sleeping.[1][3] Diagnosis is via finding the parasite in a blood smear or in the fluid of a lymph node.[3] A lumbar puncture is often needed to tell the difference between first and second stage disease.[3]

Prevention of severe disease involves screening the population at risk with blood tests for T.b.g.[1] Treatment is easier when the disease is detected early and before neurological symptoms occur.[1] Treatment of the first stage is with the medications pentamidine or suramin.[1] Treatment of the second stage involves: eflornithine or a combination of nifurtimox and eflornithine for T.b.g.[3] While melarsoprol works for both it is typically only used for T.b.r. due to serious side effects.[1]

The disease occurs regularly in some regions of sub-Saharan Africa with the population at risk being about 70 million in 36 countries.[4] As of 2010 it caused around 9,000 deaths per year, down from 34,000 in 1990.[5] An estimated 30,000 people are currently infected with 7000 new infections in 2012.[1] More than 80% of these cases are in the Democratic Republic of the Congo.[1] Three major outbreaks have occurred in recent history: one from 1896 to 1906 primarily in Uganda and the Congo Basin and two in 1920 and 1970 in several African countries.[1] Other animals, such as cows, may carry the disease and become infected.[1]