Friday, January 25, 2008

Optimism follows malaria vaccine trials

Researchers remain optimistic after the results of an initial test of a new malaria vaccine showed a six-fold increase to the body’s defense system against the mosquito-born disease. The doctors supervising the study from the Malaria Research and Training Center at the University of Bamako point out that the initial survey only included 60 participants, one-third of whom received a full dose of the vaccine, another third taking a half dose and the final third took a control dose of a licensed rabies vaccine.

Each participant received three doses of their respective treatments, spaced one month apart. And all participants showed prior exposure to malaria parasites.

From Science News:

Those who received the candidate vaccine tolerated it very well and experienced a significant boost (up to a sixfold rise) in levels of vaccine-specific antibodies, while those who received the rabies vaccine had declining levels of antibodies as the rainy season receded.

Researchers will now increase the study to include 400 children in Mali, all between the ages of one years old and six.

How to get malaria
Malaria is a parasitic infection transferred through female Anopheles mosquitoes. (Males do not feed on blood.) These mosquitoes act as transmitters of the disease by receiving the malaria parasite by simply stinging an infected person. These females usually bite at night, but they transfer the disease through saliva, injecting a protozoan parasite called Plasmodium (or in some extreme cases Plasmodium falciparum) into the bloodstream of the host (you or your friends).

Once the human (you) becomes infected, malaria develops in two separate stages: Through the liver or directly to red blood cells. If the Plasmodium heads to the liver, it can lie dormant for up to two weeks where it begins attacking by asexually reproducing inside red blood cells. Once enough of the parasite is available to attack the red blood cells, it could break out to invade other cells. This is what creates fevers in the host body, which is attempting to fight back the attack on its red blood cells. By staying within the cells, malaria evades the body’s immune system and can continue its attack.

The parasite often attacks in stages, producing cyclical periods of hot and cold in the body. For the most part, malaria causes symptoms very similar to the flu: chills, headache, muscle ache, vomiting and malaise (whatever that means). However, the Center for Disease Control warns, if malaria is left untreated some people can develop complications like brain disease, anemia and kidney failure.

Economic affects
The CDC estimates that each year 500 million are treated for malaria at a hospital or clinic. At least six out of ten of those falling sick reside in sub-Saharan Africa. Malaria kills an estimated one million people per year, and sub-Saharan Africa makes up 80 percent of those victims. In Africa, children make up a large majority of malaria deaths.

For adults who fall ill from the disease, its effect on income is substantial. Lost hours due to sick time and money spent on treatment adds up to reducing sub-Saharan Africa’s economic growth by 1.3 percent each year, according to findings from a study conducted by the World Health Organization and the London School of Hygiene and Tropic Medicine.. Taken all together, Africa has lost an estimated $100 billion if malaria had been wiped out in Africa 35 years ago

There are also researchers who claim that countries with high malaria incidences (and mortality rates) lose investment opportunities. Also, tourism and travel to that country may by inhibited by high malaria rates.

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