What is T. b. gambiense?
Trypanosoma brucei gambiense is a subspecies of the parasite responsible for causing African trypanosomiasis, commonly known as
sleeping sickness. It is endemic to West and Central Africa and is transmitted to humans through the bite of an infected
tsetse fly. T. b. gambiense is responsible for the chronic form of sleeping sickness, which can progress over months or even years.
What are the symptoms?
The disease progresses in two stages: the
hemolymphatic stage and the
neurological stage. In the early hemolymphatic stage, symptoms may include intermittent fever, headaches, joint pains, and itching. If untreated, the disease progresses to the neurological stage, where it invades the central nervous system. This stage is characterized by confusion, sensory disturbances, poor coordination, and disruptions in the sleep cycle, which gives the disease its name.
How is it diagnosed?
Diagnosis of T. b. gambiense is challenging and typically involves a combination of clinical evaluation and laboratory tests. Initial screening often involves serological tests like the
CATT. If positive, confirmation is made by detecting the parasite in body fluids, such as blood or lymph node aspirates. Cerebrospinal fluid examination is crucial to determine if the central nervous system is affected.
What are the treatment options?
Current treatment depends on the stage of the disease. In the hemolymphatic stage,
pentamidine is typically used, which is effective but comes with some side effects. For the neurological stage, treatment options include
eflornithine and
NECT (a combination of nifurtimox and eflornithine). These require hospitalization and careful monitoring due to their potential toxicity.
What are the challenges in controlling the disease?
Control of T. b. gambiense is complicated by several factors. The disease is endemic in remote areas with limited access to healthcare facilities, making it difficult to diagnose and treat. Moreover, the chronic nature of the disease means that individuals can carry the parasite for extended periods, serving as reservoirs. Additionally, the
control of tsetse fly vectors continues to be a significant challenge.
What are the recent advancements?
Recent advancements include the development of
fexinidazole, an oral medication that simplifies treatment protocols and can be administered outside of hospital settings. There are also ongoing efforts in developing vaccines, although none are currently available. Furthermore, improved diagnostic tools and strategies are being researched to enhance early detection and treatment.
What is the global impact?
Although the incidence of T. b. gambiense has decreased in recent years due to concerted efforts by organizations such as the
WHO and various NGOs, it remains a public health concern in affected regions. The socio-economic impact is significant, affecting productivity and development in endemic areas. Continued surveillance and control measures are essential to achieve the ultimate goal of eradication.
How can the disease be prevented?
Prevention strategies focus on reducing contact with tsetse flies and include wearing protective clothing, using insect repellent, and implementing community-wide vector control programs. Additionally, early detection and treatment of cases are crucial to reduce transmission. Raising awareness and training healthcare workers in endemic areas are also key components of prevention efforts.
