The Oxford University reported in the science journal Nature that malaria infection rates in Africa have dropped by 50 percent since 2000. Those numbers apply to the most lethal form of malaria in sub-Saharan Africa which is transmitted by Plasmodium falciparum, a parasitic protozoan. That 50 percent reduction rate is equivalent to 663 million new cases of malaria.
Four species of the Plasmodium genus carry malaria: P. falciparum, P vivax, P. ovale, and P. malariae. The first two are the most common. All of them are transmitted by the bites of mosquitoes from the Anopheles genus. When the mosquito bites someone, they inject the parasite into the patient’s bloodstream.
The symptoms usually start a week or two after the bite. The first symptoms include fever, chills, headache and vomiting and may not be immediately recognized as malaria. Unfortunately, if P. falciparum malaria isn’t treated within 24 hours of showing symptoms, those symptoms can become increasingly severe and eventually kill the patient.
Malaria can be both treated and prevented, and many measures have been taken to do so. People have been treated with anti-malarial drugs and they have used nets and insecticides to deal with the mosquitoes.
The researchers found that the most effective way to prevent malaria and reduce the number of people getting infected was to set up bed nets. The mosquitoes are most likely to bite somebody between 10 p.m. and 2 a.m., and most people are asleep during those hours. The bed nets prevent mosquitoes from biting people in the first place. They are coated with insecticide, and one or two people sleep under them. Each net costs around $3.00 and lasts three or four years. The Oxford researchers credited bed nets with 68 percent of the reduction in malaria cases, medications with 22 percent and pesticides with 10 percent.
Back in the 1980s, the UK Medical Research Council (MRC) conducted a study, during which they set up nets in the Gambia. The results were so encouraging that medical organizations decided to deploy nets in many other areas plagued by malaria. The UN and the Bill and Melinda Gates Foundation helped fund the bed nets.