Malaria, the dreadful mosquito-born infectious disease infects more than 200 million people a year fatally. Malaria is transmitted by an infected female Anopheles mosquito. The mosquito bite introduces the parasites into a person’s blood, which travel inside the body and reaches liver, where they mature and reproduce. A total of five species of Plasmodium can infect humans. Of this 5, most deaths are caused by P. falciparum. The other species P. vivax, P. ovale, and P. malariae generally cause a milder form of malaria. The species P. knowlesi rarely causes disease in humans.
Recently, in a research, it was found that, the protein (RIFIN) produced by some strains of the malarial parasite can cause red blood cells to form clumps. These clumps increases the severity of disease, especially in people with Blood Group A. These clumps are formed due to sticking of one cell to the other cell and also to the walls of blood vessels. They obstruct the blood flow, damage the tissues, and leads to death.
In another research it was found that, the protein produced by the strains of the malarial parasite bound weakly to the people with Blood Group O. And it does not affect these people as serious as it affects people with blood group A.