Discuss the cause, progression and prevalence of "sleeping sickness"

Answer 1

Occurring in 36 countries in sub-Saharan Africa, sleeping sickness is a vector-borne parasitic disease. This means that the disease is transmitted to humans via a carrier of a different species, or vector, while the agent of disease is a parasite. In the case of sleeping sickness, the vector is the tsetse fly, Glossina genus, which acquires the parasite, protozoa of the Trypanosoma genus, from either humans or other carrying animals. Once bitten by the tsetse fly, a person develops flu-like symptoms within weeks. If left untreated, the parasite eventually attacks the central nervous system, resulting in neurological symptoms (brain function), loss of motor control (movement), and eventually death. There are two forms of sleeping sickness, the Gambiense and the Rhodesiense. In the Gambiense form, the disease typically takes years to fully affect the body, whereas the Rhodesiense form can result in death within months. As of 2011, the estimated number of cases of sleeping sickness was 30,000, although 2009, the most recent year of reporting, saw reported cases drop below 10,000 for the first time in 50 years (World Health Organization, 2010). This drop was due to sustained prevention efforts by public-private partnerships including the WHO, pharmaceutical companies, nongovernmental organizations, and national organizations engaged in vector-control activities such as ministries of health.