March 1, 2006
UC scientists target malaria in Mali
DAVIS--Three UC Davis medical entomologists are launching a five-year federally funded project to train scientists at the University of Bamako, Mali, on strategies to combat malaria, one of the leading causes of death in that West African country.
Medical entomologist Gregory Lanzaro, director of the UC Mosquito Research Program and director of the UC Davis Center for Vectorborne Diseases (CVEC), recently received a five-year, $650,000 training grant from the Fogarty International Center, Bethesda, Md., as part of the National Institutes of Health's Global Infectious Disease Research Training Program.
"Vector control is currently the most effective measure to reduce malaria transmission," said Lanzaro, an entomology professor who is partnering with associate professor of entomology Anthony Cornel, based in Parlier, and Shirley Luckhart, associate professor of medical microbiology and immunology, UC Davis School of Medicine.
"It is critically important that our UC Davis Malaria Vector Training Program provide Mali trainees with a solid background in insecticide resistance monitoring and other management methodologies," Lanzaro said. "A second, more ambitious strategy in our program involves the release of genetically modified mosquitoes for either population suppression or replacement."
The training will take place on both university campuses. Lanzaro will train the Mali vector biologists in population genetics; Cornel will instruct them in insecticide resistance, and Luckhart will explain the interactions between mosquitoes and Plasmodium parasites, which cause malaria.
Malaria spreads through the bite of Anopheles gambiae mosquitoes infected with the Plasmodium parasite. More than 800,000 reported cases of malaria occur annually among Mali's 11 million residents, according to the World Health Organization (WHO). The malaria mortality rate varies between 16 and 25 percent, with children under age five and pregnant women the most vulnerable.
The percentage of children under age five who die from malaria rose from 45.7 percent in 2000 to 50 percent in 2002, according to the Mali Ministry of Health. An estimated 80 to 90 percent of children younger than five carry Plasmodium parasites during the rainy season.
Intensive efforts to eliminate malaria are largely ineffective, Lanzaro said, because many African countries lack the infrastructures and resources necessary to mount sustainable campaigns against malaria. Traditionally, industrialized countries invest very little in malaria research in Africa.
WHO endorses the use of insecticide-treated bed nets to kill Anopheles vectors. However, insecticide resistance now "presents a serious threat to the success of the program," he noted. Drug resistance also challenges the malaria-eradication program.
"We need more innovative strategies to control the spread of malaria," Lanzaro said. One way is to release genetically modified mosquitoes carrying genes that resist or kill mosquito vectors in wild populations.
In addition, sterile males could be released to collapse female reproduction activity. Only female mosquitoes are blood-suckers, Lanzaro noted. The female needs the protein to develop her eggs.
One of the world's oldest and deadliest diseases, malaria kills between 1.5 million and 2.5 million people each year, primarily in Africa. Malaria kills a child in Africa every 10 to 15 seconds, or some 8,000 children per day. WHO estimates that 90 percent of the global incidence of malaria occurs in Africa, and that 35 of the 44 countries with intensive malaria are in Africa. Nine out of 10 deaths due to malaria are among sub-Saharan African children younger than age five.
Plasmodium falciparum, the most deadly parasite that the Anopheles mosquito transmits, can kill within hours of noticeable symptoms, which include high fever, severe headache, drowsiness, delirium and confusion.
The UC Davis Center for Vectorborne Diseases has provided training opportunities for scientists from African and Latin American countries over the past decade. The three UC Davis entomologists have all worked closely with the Malaria Research and Training Center (MRTC) at the University of Bamako.
Lanzaro, who received his doctorate in medical entomology from the University of Florida in 1986, has worked on the biology of Anopheles mosquitoes for 25 years. He has conducted field research in Mali since 1991, and also in Cameroon.
Cornel, a native South African who completed his doctorate at the University of the Witwatersrand in 1993 in mosquito systematics, has conducted field work in South Africa since 1988, and in Mali and Cameroon since 2003.
Luckhart, who completed her doctorate in entomology from Rutgers in 1995, has worked on insect innate immunity for nearly 20 years and is currently focused on Anopheles mosquito-malaria parasite interactions. She conducted field research in Kenya in collaboration with the U.S. Army from 1999-2001.
Media Contact: Kathy Keatley Garvey, (530) 754-6894, firstname.lastname@example.org
Further information on mosquito research is available on the UC Mosquito Research Program Web site at www.ucmrp.ucdavis.edu.