Traducción artículo de revista sobre la malaria

TACLING MALARIAInterventions available today could lead to decisive gains in prevention and treatment--if only the world would apply themLong ago in the Gambia, West Africa, a two-year-old boy named Ebrahim almost died of malaria. Decades later Dr. Ebrahim Samba is still reminded of the fact when he looks in a mirror. That is because his mother-who had already buried several children by the timehe got sick-scored his face in a last-ditch effort to save his life. The boy not only survived but eventually became one of the most well-known leaders in Africa: Regional Director of the World Health Organization.Needless to say, scarification is not what rescued Ebrahim Samba. The question is what did? Was it the particular strain of parasite in his blood that day, his individual genetic orimmunological makeup, his nutritional state? After centuries of fighting malaria-and conquering it in much of the world--it is amazing what we still do not know about the ancient scourge, including what determines life and death in severely ill children in its clutches. Despite such lingering questions, however, today we stand on the threshold of hope. Investigators are studying malaria survivors andtracking many other leads in efforts to develop vaccines. Most important, proven weapons--principally, insecticide-treated bed nets, other anti-mosquito strategies, and new combination drugs featuring an ancient Chinese herb--are moving to the front lines.In the coming years the world will need all the malaria weapons it can muster. After all, malaria not only kills, it holds back human andeconomic development. Tackling it is now an international imperative.A Villain in AfricaFOUR PRINCIPAL SPECIES of the genus Plasmodium, the parasite that causes malaria, can infect humans, and at least one of them still plagues every continent save Antarctica to a lesser or greater degree. Today, however, sub-Saharan Africa is not only the largest remaining sanctuary of P. falciparum--the most lethalspecies infecting humans--but the home of Anopheles gambiae, the most aggressive of the more than 60 mosquito species that transmit malaria to people. Every year 500 million falciparum infections befall Africans, leaving one million to two million dead--mainly children. Moreover, within heavily hit areas, malaria and its complications may account for 30 to 50 percent of inpatient admissions and upto 50 percent of outpatient visits.The clinical picture of falciparum malaria, whether in children or adults, is not pretty. In the worst-case scenario, the disease's trademark fever and chills are followed by dizzying anemia, seizures and coma, heart and lung failure--and death. Those who survive can suffer mental or physical handicaps or chronic debilitation. Then there are people like EbrahimSamba, who come through their acute illness with no residual effects. In 2002, at a major malaria conference in Tanzania where I met the surgeon-turned-public health leader, this paradox was still puzzling researchers more than half a century after Samba's personal clash with the disease. That is not to say we have learned nothing in the interim regarding inborn and acquired defenses againstmalaria. We now know, for example, that inherited hemoglobin disorders such as sickle cell anemia can limit bloodstream infection. Furthermore, experts believe that antibodies and immune cells that build up over time eventually protect many Africans from malaria's overt wrath. Ebrahim Samba is a real-life example of this transformed state following repeated infection; after his early brush with death, hehad no further malaria crises and to this day uses no preventive measures to stave off new attacks. (As a tropical medicine doctor, all I can say is: Don't try this on safari, folks, unless you, too, grew up immunized by hundreds of malarial mosquitoes every year.) Samba's story also has another lesson in it. It affirms the hope that certain vaccines might one day mimic the protection that...