ANDREA BRADY BIOL 062 African trypanosomiasis (Sleeping Sickness)

Epidemics have killed hundreds of thousands since no.html 76.jpg

Tens of thousands continue to die each year WHO estimated that in 2001, there were 48,000 deaths caused by sleeping sickness.

Tens of thousands continue to die each year WHO estimated that in 2001, there were 48,000 deaths caused by sleeping sickness. Currently, it is estimated the number of deaths per year has increased to 50,000 or as high as 100,000.

As many as 500,000 are currently infected.

Chart from World Bank, Most cases are found in Sub-Saharan Africa.

How can an infectious disease be contained to such a specific region of the world?

How can an infectious disease be contained to such a specific region of the world? Let’s take a closer look at how the disease is spread…

Disease Transfer The disease is caused by two parasites of the Trypanosoma Genus and brucei Species

Disease Transfer The disease is caused by two parasites of the Trypanosoma Genus and brucei Species. More commonly called Trypanosomes

Trypanosomes are protozoans. ces11512cvf.gif

Trypanosomes are protozoans.  (unicellular eukaryotes)  (single flagellum) ces11512cvf.gif

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Disease Transfer The trypanosomes are mainly transferred by the tsetse fly, which is found primarily in Sub- Saharan Africa. the tsetse fly The tsetse fly

Areas Infested by the Tsetse Fly

Distribution Map for African Sleeping Sickness rican_trypano/clip_image002.jpg

Areas Infested by tsetse fly Distribution of the disease

Trypanosoma brucei: Two different parasites African Sleeping Sickness is caused by two different parasites.

Trypanosoma brucei: Two different parasites African Sleeping Sickness is caused by two different parasites. Trypanosoma brucei gambiense Trypanosoma brucei rhodesiense

Trypanosoma brucei: Two different parasites Trypanosoma brucei gambiense Accounts for 90% of reported cases of African Sleeping Sickness. Causes the chronic form of the disease Prevalent mostly in West and Central Africa. ypano.html 59/en/

Trypanosoma brucei: Two different parasites Trypanosoma brucei rhodesiense Accounts for 10% of reported cases of African Sleeping Sickness. Causes the acute form of the disease. Prevalent mostly in Eastern and Southern Africa. ypano.html 59/en/

Method of Infection Begins with the bite of the tsetse fly

Method of Infection The bite will become red and swollen.

Method of Infection The bite will become red and swollen. From here, the infection will enter the bloodstream.

Method of Infection The bite will become red and swollen. The infection will enter the bloodstream. Long asymptomatic phase.

The disease has three distinct stages.

 Asymptomatic Phase 

The disease has three distinct stages.  Asymptomatic Phase  First Stage (haemolymphatic phase) 

The disease has three distinct stages.  Asymptomatic Phase  First Stage (haemolymphatic phase)  Second Stage (neurological phase) 

First Stage The pathogens will spread throughout the blood and the lymph.

First Stage Symptoms  Fever  Headache  Sweating  Joint Pain  Itching  Swollen Lymph Nodes  nterbottom%27s_sign.jpg/200px-Winterbottom%27s_sign.jpg

Second Stage Eventually, the disease will manage to cross the blood-brain barrier.

Second Stage Eventually, the disease will manage to cross the blood-brain barrier. This will cause an infection of the Central Nervous System

Second Stage Symptoms  Confusion  Sensory Disturbances  Poor Coordination  Disturbances of Sleep Cycles 8cac-423baecb957f.jpg

If not treated, the disease is fatal.

Diagnosis and Treatment Treatment varies depending on the stage of the disease.

Diagnosis and Treatment The disease is easier and more effective to treat the earlier it is diagnosed.

Diagnosis and Treatment The disease is easier and more effective to treat the earlier it is diagnosed. Much harder after the pathogens have crossed the blood-brain barrier.

Diagnosis and Treatment Four drugs are available for treatment 01.gif

Diagnosis and Treatment Four drugs are available for treatment  Two available for first- stage treatment  Two available for second-stage treatment  

Diagnosis and Treatment The two drugs available for second- stage treatment are significantly more dangerous.

Diagnosis and Treatment So, in summary, treatment during the first-stage is…

Diagnosis and Treatment So, in summary, treatment during the first-stage is…  More effective scientist.com/content/figures/images/yr2002/may13/iv.jpg

Diagnosis and Treatment So, in summary, treatment during the first-stage is…  More effective  Safer scientist.com/content/figures/images/yr2002/may13/iv.jpg

Diagnosis and Treatment Therefore, early diagnosis is imperative chaftliches_engagement/aerztin_patient_205.jpg

Like with malaria, if we could reduce the number of people with the disease, we could reduce transmissions and eventually eradicate the disease.

Organizations like WHO have began efforts to eliminate the risk of this disease

Organizations like WHO have began efforts to eliminate the risk of this disease HAT programme

Due to lack of funds and turmoil, there are an estimated 7 nations currently at “epidemic” level for the disease.

Like many other infectious diseases in third world countries, much change is needed in world health policies before we can effectively eradicate African Sleeping Sickness.

THE END.