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Malaria vaccine fails to protect people in Mali

a malaria vaccine tried out in Mali in 2003 was not suited to protect people from the pathogen prevalent in the area, according to a joint study by researchers in Mali and the us. The researchers studied samples from people in Bandiagara, a rural town in northeastern Mali, and found that before administering the vaccine, its possible effect on the strain of mosquito being targeted was not taken into consideration.

Reporting the results of the study in the online journal Public Library of Science (plos) in November 2006, the researchers from University of Maryland School of Medicine, usa, University of Bamako, Mali, and National Institutes of Health, Bethesda, said the results showed the importance of determining the genetics of the pathogens before starting vaccine trials.

The main vector in the Mali countryside is Anopheles gambiae, which spreads the pathogen Plasmodium falciparum. A variety of strains of Plasmodium can cause malaria and different strains produce different antigens. These antigen are used to make vaccines. A vaccines is effective if it contains the same antigen as the parasite it has to produce antibodies against.

The research team collected 1,300 blood samples from malaria patients between July and January each year (1999-2001). They sequenced their dna to examine the presence of a particular gene