Long Drive

• How is a protozoan parasite different from bacteria and multi-celled parasites such as intestinal worms?

Bacteria have no true nucleus or membrane bound organelles, such as mitochondria. Protozoa do have many complex organelles within their cytoplasm (Anderson, 2014). A parasite is different than bacteria in the type of leukocyte that will accumulate as a result of an infection. Bacteria will have a strong reaction by neutrophils, while parasites will bring about more eosinophils.

• How does T. brucei differ from the closely related American trypanosome T. cruzi, the causative agent of Chagas disease, and from the P. falciparum parasite that causes malaria? Describe notable differences in morphology, life cycle, infectivity, transmission, geographical range, disease presentation, and treatment.

The life cycle of T. brucei starts as stage one of the disease in a fly which then transmits eggs to a human reservoir via the blood stream, after 3 weeks the blood brain barrier is crossed and the second stage of the disease starts as neurological affects are produced. This parasite is found only in Africa (Global Health - Division of Parasitic Diseases and Malaria, 2012). This differs from the close relative T. cruzi, which is only located in America, along with the fact that feces must enter a wound or body in another way for the latter infection to be produced (Global Health - Division of Parasitic Diseases and Malaria, 2012).

• How do people become infected with T. brucei? What are the risk factors as far as behavior, lifestyle, and geographic location?

People become infected with T. brucei by a tsetse fly. There are other ways of becoming infected like mother to child during labor. People are most at risk to be bitten during the daylight hours near rivers or streams, or in heavily wooded areas (Global Health - Division of Parasitic Diseases and Malaria, 2012).