Malarial parasites asexual stages

Malaria. Malaria infection occurs in over 30% of the world s population and almost exclusively in developing countries. Approximately 150 X 10 cases occur each year, with one million deaths occurring in African children (87). The majority of the disease in humans is caused by four different species of the malarial parasite. Vaccine development is problematic for several reasons. First, the parasites have a complex life cycle. They are spread by insect vectors and go through different stages and forms (intercellular and extracellular sexual and asexual) as they grow in the blood and tissues (primarily fiver) of their human hosts. In addition, malaria is difficult to grow in large quantities outside the natural host (88). Despite these difficulties, vaccine development has been pursued for many years. An overview of the state of the art is available (89). 

Perlman, H., Berzins, K., Wahlgren, M., Carlsson, J., Bjorkmin, A., Patarroyo, M. E., and Perlmaann, P. (1984) Antibodies in malarial sera to parasite antigens in the membrane of erythrocytes infected with early asexual stages of Plasmodium falciparum J. Exp. Med. 159,1686-1704. 

Krungkrai, J., Burat, D., Kudan, S., Krungkrai, S., and Prapunwattana, P. (1999) Mitochondrial oxygen consumption in asexual and sexual blood stages of the human malarial parasite, Plasmodium falcipamm. Southeast Asian J Trop Med Public Health 30 636-642. 

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