Trypanosoma cruzi :: Essays Papers

Trypanosoma cruzi Life History: Trypanosoma cruzi, a protozoan parasite, is the causative agent of Chagas disease. It is most commonly found among people, dogs, cats, and wild mammals in Central and South America, especially in rural communities where people reside in houses constructed from mud or thatch. The vector is the reduviid or kissing bug, which lives in the cracks of buildings and substandard houses8. Often substandard housing/living conditions are shown to have these structural fractures, which provide suitable habitats for reduviid bugs. The reduviid bug transmits T. cruzi by rubbing its own contaminated feces into an abrasion (wound or bug bite) or a mucous membrane of the host. Two other modes of infection are blood transfusions/organ transplants and perinatal/vertical transfer from mother to child3. In addition, there have been reports that infections originated from undercooked food that was contaminated8. The life cycle of T. cruzi: The vector, reduviid bug, bites and defecates on host. Parasites, in the form of trypomastigotes, are able to enter the blood via mucous membranes or a cut. During cell invasion, the trypomastigotes transform into amastigotes and undergo multiplication. Parasites are then released into the blood stream as trypomastigotes where they either spread to other tissues or are taken up by the vector to perpetuate the life cycle2. Chagas disease: Chagas disease exists in three stages: acute, indeterminate, and chronic. 1. The acute stage manifests shortly after infection from a bite or alternate mode of transmission and is generally found in only 1% of reported cases8. Although it is often asymptomatic, symptoms can include Romaà ±a’s sign (one swollen eye), fever, fatigue, enlarged liver/spleen, swollen lymph nodes, rash, loss of appetite, diarrhea, and vomiting. In adults, these symptoms generally subside within 4-8 weeks and may or may not require treatment. Very young children are a concern because they may sustain severe brain damage or die as a result of infection8. 2. The indeterminate stage may also be asymptomatic. Onset of this stage is reported about 8-10 weeks following infection and may persist for years. 3. The chronic stage is the most severe and the most common manifestation of Chagas disease. Chronic Chagas disease usually presents itself 10-40 years after infection, in about 30% of infected individuals. On average, developing this class of Chagas