African Trypanosomiasis

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African Trypanosomiasis

• African Sleeping Sickness
• Kristen Sena
• Period 2

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General Information

• Two types East and West
• Infection is caused by the bite of an infected
  tsetse fly that are only found in Africa
• It is caused by the protist Trypanosoma Brucei
• The tsetse fly is only found in rural areas of
  Africa
• If left untreated the victim will lapse into a
  coma and eventually death
• It is estimated that 500,000 people are currently
  infected with this disease
• It also can infect the livestock of the rural
  population in Africa

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History and Transmission

• History The African Sleeping Sickness has been
  present in Africa since at least the 14th century
  and was identified in 1903 by Sir David Bruce on
  what is now the country of Mail. In 1960 the
  disease was almost eliminated and then surged
  back as the health systems began to fail because
  of political problems and war in Africa
• Methods of transmission
• -Mother to child (crosses the placenta)
• -Laboratories (can be transmitted through organ
  transplants but this is uncommon)
• -Blood transfusion
• -Infected Tsetse fly bite

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West vs East Sleeping Sickness

• West Found in Central and West Africa, rarely
  carried to America, Symptoms show within a few
  months to a year, death occurs after several
  years if not treated, caused by Trypanosoma
  brucei gambiense
• East Found in South and East Africa, more easily
  carried to America than is West, Symptoms show
  within 1-3 weeks and death occurs after several
  months if not treated, caused by Trypanosoma
  brucei rhodesiense

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Symptoms

• West and East chancre sores, fever, severe
  headaches, irritability, extreme fatigue, swollen
  lymph nodes, aching muscles and joints, can
  invade CNS and cause neurological problems
  including confusion and personality changes, some
  develop a skin rash, enlarged spleen, and
  increased heart rate
• Symptoms only found in West swelling of face and
  hands, itching skin, weight loss, daytime
  sleepiness and nighttime disturbances

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Tests and Treatment

• Tests include a blood sample and sometimes a
  spinal tap
• Treatment depends on the patients lab results but
  it includes the drug Melarsoprol made of an
  arsenic and anti-freeze compound, but this drug
  is very dangerous and kills about 15-20 of those
  treated, another drug that used to be
  manufactured is eflornithine. The production of
  this miracle drug stopped because of the high
  cost of manufacturing it, low profit, and the
  negative effect It had on treating cancer which
  was its original purpose.
  

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Effect and Potential treatment

• The parasite overcomes the bodies defenses
  causing anemia, endocrine, cardiac, kidney
  diseases and disorders. It enters into a
  neurological state when it passes through the
  blood-brain-barrier
• Potential treatment A team of CNRS researchers
  has found protein within the parasite and
  without this protein, the protist would not be
  able to feed itself causing it to die. The
  researches are trying to find a way to eliminate
  or prohibit this protein from functioning within
  the parasite.

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The Infection

• The parasite lives in the gut of the fly and
  travels into the saliva when it bites infecting
  either a human or animal. The protist lives in
  the bloodstream of the host but often will travel
  to other parts of the body after infection.

- The Tsetse fly is found in rural areas and
bites during the day light hours. They inhabit
forests and thick vegetation along rivers and
water holes. The majority of the flies in Africa
do not carry this protist.
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Cell Structure

• Mostly like a eukayotic cell
• Unusual features a single large
• mitochondria with condensed
• mitochondria DNA and is associated with the
  flagellum
• The surface of the cell also has a dense coat of
  glycoproteins to avoid the immune system of its
  host. It does this by frequent genetic
  modification or switching allowing a new VSG
  coat to be created. This way it is constantly
  avoiding the immune respose that recognizes it
  and tries to eliminate it by changing the active
  expression or by changing the VSG gene in the
  active site. This creates a chronic infection.

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Reproduction

• The constant switching of its outer protein coat
  allows it to be unrecognizable and allows time
  for reproduction.
• This pathogen undergoes a mitotic process but is
  different in the cytoskeletal process.
• -The basal body replicates
• -The kinetoplast replicates and the two daughter
  cells are seaerated by the basal bodies
• -The second flagellum grows and the nucleus
  replicates
• -The mitochondria divides and cytokinesis occurs

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Effect on the Body

• After the fly bites the protist enters the
  bloodstream and begins to avoid the bodies immune
  system by antigenic variation. While this is
  ocuring it gives the protist a chance to
  replicate and inhabit other parts of the body.
  The replicated protists move throughout the body
  and begin affecting the bodies organs. In
  advanced cases of this disease the parasite
  invades the central nervous system and can change
  the patients behavior and cause other
  neurological problems