VANCOUVER, Washington — In areas where malaria is prevalent, screening blood transfusions for the disease is uncommon. According to a report the in Oxford Journals, parts of sub-Saharan Africa cannot afford to lose blood, even if the blood is infected. The region often experiences “severe blood shortages,” which “would be exacerbated by rejecting blood that contained malaria parasites.” Additionally, even when blood is tested in resource-poor areas, the tests “are not sensitive enough to detect low levels of parasites.”
The World Health Organization says that the parasite that causes malaria, called Plasmodium, multiplies in the liver and then proceeds to contaminate red blood cells. This infection initially results in fever, headache and vomiting. However, if left untreated, malaria parasites “can quickly become life-threatening by disrupting the blood supply to vital organs.”
According to the Centers for Disease Control and Prevention, in countries with high rates of malaria, children and pregnant women with compromised immune systems are the most vulnerable to infection. The Oxford Journals states, “When malaria is transmitted through a blood transfusion to a non-immune recipient, it can be rapidly fatal.” Furthermore, it is unknown how recipients with semi-immunity will respond to infected blood. There is little in the way of conclusive research on the matter because the level of immunity is dependent on the prevalence of malaria regionally.
Maintaining a sufficient supply of blood has been an issue in sub-Saharan Africa for decades. The Oxford Journals reports that in the African country of Benin, over 30 percent of donors test positive for malaria. However, mortality rates would go up if infected blood were rejected.
The Lancet claims that “timely access to safe blood transfusions” would greatly reduce the number of maternal deaths that occur in Africa, which make up half of the maternal deaths worldwide. The Oxford Journals states that between 1970 and 2007, 26 percent of maternal hemorrhage deaths were specifically attributed to “lack of available blood for transfusion.”
For now, researchers have concluded that developing more sensitive tests for malaria is necessary to stop malaria infected blood from reaching transfusion recipients. While many living in areas where malaria is prevalent have developed some degree of immunity, children and pregnant women have notably weaker immune systems and receiving infected blood could prove fatal.
Development of new tests will be a long, difficult process. The Oxford Journals says that while microscopic evaluation of blood in areas where malaria is not endemic would be reasonable, the same testing could not be used in areas with high rates of malaria. For these areas, highly sensitive quantitative nucleic acid sequence-based amplification would be necessary, but “are not currently affordable or practical for routine malaria screening.”
Wealthy countries have developed new technology to reduce the amount of dangerous pathogens in blood. However, since blood is almost always donated whole (as opposed to in individual components, such as platelets,) this is not a reasonable or affordable solution for sub-Saharan Africa.
Alternative solutions to screening for malaria have been considered. For example, “adding antimalarials to the blood pack, marking units that test positive for malaria, and only screening blood destined for neonates” would reduce the need for in-depth testing.
– Bridget Tobin
Sources: CDC, World Health Organization, The Lancet, Oxford Journals