Interestingly, human carriers of the recessive gene for sickle-cell anemia are more resistant to Malaria than others.
That means that if there were a world-wide pandemic of Malaria, then, if all other things were equal, black people would have a considerable survival advantage over white people.
But of course, wealth and the availability of treatments changes the entire equation.
Malaria
From Wikipedia, the free encyclopedia
There are several families of drugs used to treat malaria. Chloroquine was the antimalarial drug of choice for many years in most parts of the world. However, resistance of Plasmodium falciparum to chloroquine has spread recently from Asia to Africa, making the drug ineffective against the most dangerous Plasmodium strain in many affected regions of the world.
There are several other substances which are used for treatment and, partially, for prevention (prophylaxis). Many drugs can be used for both purposes; larger doses are used to treat cases of malaria. Their deployment depends mainly on the frequency of resistant parasites in the area where the drug is used.
Currently available anti-malarial drugs include:
* Artemether-lumefantrine (Therapy only, commercial name Coartem)
* Artesunate-amodiaquine (Therapy only)
* Artesunate-mefloquine (Therapy only)
* Artesunate-Sulfadoxine/pyrimethamine (Therapy only)
* Atovaquone-proguanil, trade name Malarone (Therapy and prophylaxis)
* Quinine (Therapy only)
* Chloroquine (Therapy and prophylaxis; usefulness now reduced due to resistance)
* Cotrifazid (Therapy and prophylaxis)
* Doxycycline (Therapy and prophylaxis)
* Mefloquine, trade name Lariam (Therapy and prophylaxis)
* Primaquine (Therapy in P. vivax and P. ovale only; not for prophylaxis)
* Proguanil (Prophylaxis only)
* Sulfadoxine-pyrimethamine (Therapy; prophylaxis for semi-immune pregnant women in endemic countries as "Intermittent Preventive Treatment" - IPT)
The development of drugs was facilitated, when Plasmodium falciparum was successfully cultured.<18> This allowed in vitro testing of new drug candidates.
Since 2001 the World Health Organization has recommended using artemisinin-based combination therapy (ACT) as first-line treatment for uncomplicated malaria in areas experiencing resistance to older medications. The most recent WHO treatment guidelines for malaria recommend four different ACTs. While numerous countries, including most African nations, have adopted the change in their official malaria treatment policies, cost remains a major barrier to ACT implementation. Because ACTs cost up to twenty times as much as older medications, they remain unaffordable in many malaria-endemic countries.
Extracts of the plant Artemisia annua, containing the compound artemisinin or semi-synthetic derivatives (a substance unrelated to quinine), offer over 90% efficacy rates, but their supply is not meeting demand.
A 2005 study published in Nature Structural And Molecular Biology (NSMB) described possible drug resistance, although the finding could help the development of other drugs.<19> These findings contradict other findings published at Plos Genetics which suggest the mitochondria as the major target of action of artemisinin and its analogs. The paper published at NSMB has gained support from the observation that mutations in the proposed target for artemisinins (PfATP6) are associated with decreased sensitivity to artemether in parasites studied in French Guiana by a team based at the Institute Pasteur.
In February 2002, the journal Science and other press outlets<20> announced progress on a new treatment for infected individuals. A team of French and South African researchers had identified a new drug they were calling "G25."<21> It cured malaria in test primates by blocking the ability of the parasite to copy itself within the red blood cells of its victims. In 2005 the same team of researchers published their research on achieving an oral form, which they refer to as "TE3" or "te3."<22> As of early 2006, there is no information in the mainstream press as to when this family of drugs will become commercially available.
Although effective anti-malarial drugs are on the market, the disease remains a threat to people living in endemic areas who have no proper and prompt access to effective drugs. Access to pharmacies and health facilities, as well as drug costs, are major obstacles. Médecins Sans Frontières estimates that the cost to treat a malaria-infected person in an endemic country is between US$0.25 and $2.40.<23>
There is a problem of availability of effective malaria treatments in the United States. Most hospitals in the United States do not stock intravenous quinine, and with the reduced use of quinidine by cardiologists, many hospitals have no access to intravenous anti-malarial drugs at all.
<snip>
Vaccination
Vaccines for malaria are under development, with no completely effective vaccine yet available (as of June 2006). A team backed by the PATH Malaria Vaccine Initiative, a grantee of the Gates Foundation, and the pharma giant GlaxoSmithKline have announced results of a Phase IIb trial for RTS,S/AS02A, a vaccine which reduces infection risk by approximately 30% and severity of infection by over 50%. The study looked at over 2000 Mozambican children.<36> Further research will delay this vaccine from commercial release until around 2011.
In January 2005, University of Edinburgh scientists announced the discovery of an antibody which protects against the disease. The scientists will lead a £17m European consortium of malaria researchers.<37> It is hoped that the genome sequence of the most deadly agent of malaria, Plasmodium falciparum, which was completed in 2002, will provide targets for new drugs or vaccines.<38>
More:
http://en.wikipedia.org/wiki/Malaria
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