Malaria Is the Word's Most Important Vector-Borne Disease

Malaria is the word's most important vector-borne disease. It is currently endemic (found

in a particular area or a particular group of people), and 2400 million people are at risk to

develop malaria (Martens et al., 1999). More than 90% of the worldwide cases are

reported in sub-Saharan Africa; Asia and Americas are thought to have 5-2o million cases per year, where 80% of these occur in Asia (Anderson et al., 1996). Million deaths

are caused by malaria every year, especially in young children in rural Africa (Hales and

Woodward, 2003) where malaria is responsible for the deaths of one in 20 children

before the age of five (Anderson et al., 1996).

But what is malaria and how is transmitted? Well, malaria is an infectious disease which

is conveyed from person to person by a mosquito. There are 422 species of mosquitoes

around the world but only about 70 species are vectors of malaria. The main vector

species in Africa, the Anopheles gambiae complex, is the major factor for the

transmission of this disease to humans (Martens et al., 1999). In addition, malaria is

caused by species of parasites which belong to the genus Plasmodium: Plasmodium

vivax, P.falciparum,P.ovale, and P. malariae. P.falciparum is the most common species

in tropical areas and the most dangerous clinically, while P.vivax has the most extensive

geographic range and is present in many temperate zones as well as the tropics and

subtropics. The transmission occurs through the female mosquitoes which require blood

for the development of her eggs (Anderson et al. 1996). Thus, P.vivax and P.falciparum

have different roles on the transmission