Navigation Links
Understanding Sleeping Sickness

Sleeping sickness or Human African trypanosomiasis is caused by the bite of an insect , called the glossinid tse-tse fly//, which passes on the parasite called the trypanosome, to human beings through the bite. There has been a come-back of this disease over the past two decades in Sub-Saharan Africa. The World Health Organization (WHO) has tried to collect the data of the number of people suffering this sickness, which is about 300,000, as mentioned in a 1998 communiqué. Evolved screening and treatment measures have indeed resulted in a considerable decline in the infection rates of this disease.

Sleeping sickness classically manifests itself in two forms, corresponding to two parasite subspecies. The chronic form, encountered in Central and West African countries, is caused by Trypanosoma brucei gambiense (T.b. gambiense). Its development cycle in the host vaires greatly, from a few months to several years. The acute form of the disease is brought on by Trypanosoma brucei rhodesiense (T.b. rhodesiense), in southern and eastern African countries. The infection it induces takes effect after a few weeks. More virulent than the chronic form, its development cycle is also more rapid and, consequently, clinical detection can be made earlier.

However, it is increasingly recognized that the existence of these two forms, the chronic one due to T. b. gambiense and the acute one provoked by T. b. rhodesiense, only partly reflect the real mechanisms at work. Concerning the Gambian form, the screening and treatment teams indicates the occurrence of several categories of subjects infected: some show Glossina fuscipes gorged with blood affected by classical chronic forms of the disease; others bear severe rapidly developing forms; still other people show no symptoms of human African trypanosomiasis, in spite of a long period of infection. This diversity in host clinical presentation in reaction to infection can have several sources: the host's ability to r espond to infection, the degree of parasite virulence or pathogenicity and the environment.

An IRD team focused particularly on the role of host genetic diversity in response to T. b. gambiense infection (whether or not the disease develops). As human experimentation is excluded, genetic, epidemiological and statistical methods, all brought under the term genetic epidemiology, were developed in order to identify the chromosome regions and/or DNA mutations involved in the development of the disease. The researchers used association techniques in order to determine the influence of certain mutations on the DNA of genes coding for particular immune system proteins (cytokines) in manifestation of the disease. This type of study consists in comparing the frequency of a mutation in subjects with symptoms and in healthy individuals. When the frequency of a mutation is significantly higher in the sick subjects than in the healthy ones, this mutation is associated with an enhanced risk of developing the disease. Conversely, a significantly lower frequency is an expression of a protective effect conferred by the mutation.

The two studies conducted in two distinct foci of the disease, respectively at Sinfra in the Ivory Coast and at Bandundu in the Democratic Republic of Congo (1), revealed evidence of three associations between a DNA mutation and the development of the disease. Depending on their position on certain cytokines genes, the mutations investigated were shown to be capable of inducing in the subject carrying them an increased risk of developing this human trypanosomiasis, or conversely a higher chance of a protector effect (2).

The associations brought out between these mutations and the disease necessitate work to confirm this in different populations and environments. New investigations, particularly in genetic epidemiology, are currently being put into operation in order to check up on possible effects of genetic predisposition already observed. The results obtained will help improve our knowledge about host-parasite interactions, by means of identifying genetic markers signalling risk. That should open the way in the long term to possible development of innovative control strategies against sleeping sickness.


Related medicine news :

1. Understanding The Predictors Of Prostate Cancer
2. Understanding Restless Legs Syndrome
3. Understanding Lung Cancer Metastasis
4. Understanding The Link Between Hormone Replacement and Respiratory Disease
5. Understanding The Risks Of Hormone Therapy
6. Understanding The Link Between Metabolic Syndrome And Drinking Patterns
7. A Better Understanding Of The Brain Network
8. Understanding The Predictor’s Of Alzheimer’s Diseae
9. Understanding The Harmful Effects Of Radiation Exposure
10. Understanding The Origin Of Tumors
11. Understanding Insulin Resistance
Post Your Comments:

(Date:10/13/2015)... ... October 13, 2015 , ... ... have developed valuable new strategies for enrolling and serving insurance consumers who do ... obtain health insurance and pay monthly premiums. In “Health Plan Engagement Strategies: The ...
(Date:10/13/2015)... (PRWEB) , ... October 13, 2015 , ... ... smoke-free communities, and the Florida Apartment Association (FAA) has partnered with the Florida ... communities meet the demand. , The FAA Smoke-Free Multifamily Housing Program launched ...
(Date:10/13/2015)... ... 13, 2015 , ... Just under three months ago, eMarketing Concepts ... promotion – effectively offering all of their services for just a buck in the ... flooded with phone calls from interested buyers. As a genuine one-stop-shop for internet marketing, ...
(Date:10/13/2015)... ... October 13, 2015 , ... ... a new PDF automation tool to batch conversions of CAD drawings, plans, ... 100% document fidelity. , CADConverter eliminates the complexity requirement of specialized applications to ...
(Date:10/13/2015)... (PRWEB) , ... October 13, 2015 , ... The Bill ... in San Diego, also offering expert reconstruction and flood remediation services. Family-owned and operated ... They have been named the Best San Diego plumber two years in a row ...
Breaking Medicine News(10 mins):
(Date:10/12/2015)... Va. , Oct. 12, 2015  Today, Divurgent is ... of Advisory Services. As a former CIO, Paul brings 15 ... not just understand or sympathize with today,s CIOs, he is ... the same challenges Paul has faced, and his new role ... in ensuring technology efficiencies across an organization. ...
(Date:10/12/2015)... DENVER , Oct. 12, 2015 Beginning ... ICD-10 Codes. Therapy Partner, the fastest growing practice management ... automated technology that easily converts all patient diagnostic codes ... --> --> ... Brief for all mental health practitioners to easily understand ...
(Date:10/12/2015)... INDIANAPOLIS , Oct. 12, 2015 Eli ... ACCELERATE study,s academic leadership have accepted the recommendation of ... 3 trial of the investigational medicine evacetrapib, due to ... the treatment of high-risk atherosclerotic cardiovascular disease and will ... --> --> The independent data ...
Breaking Medicine Technology: