Lauran Neergaard
The Associated Press
Friday, December 08, 2006
Malaria is fuelling the spread of AIDS in Africa by boosting the HIV in people's bodies for weeks at a time, says a study that pins down the deadly interplay between the dual scourges.
It's a vicious cycle as people weakened by HIV are, in turn, more vulnerable to malaria.
University of Washington researchers, who estimated the impact of the overlapping infections, concluded that the interaction could be blamed for thousands of HIV infections and almost a million bouts of malaria over two decades in just one part of Africa.
The research, published in Friday's edition of the journal Science, highlights the need for a joint attack on both epidemics.
"It's an important paper," said Dr. Anthony Fauci of the National Institutes of Health, the government's leading infectious disease specialist. "We really need to be much more serious about what we do about malaria at the same time we're serious about what we do about HIV."
Anti-malaria programs, such as a $1.2 US billion initiative in its early stages, "assume a much, much greater imperative when you realize not only are you going to have an impact on one disease, but you might impact another disease," Fauci added.
Malaria sickens up to half a billion people annually and kills more than one million, mostly young children and mostly in Africa -- which also bears the biggest HIV burden. Sub-Saharan Africa is home to 24.7 million HIV-infected people; about two million died this year, according to the latest UN update.
Scientists long have suspected the two diseases fuel each other. The new study created a mathematical model to figure out just how much they do.
HIV is most easily spread when patients have high virus levels in their blood. A bout of malaria causes a temporary surge -- a stunning sevenfold increase -- in those levels, said lead researcher Laith Abu-Raddad, a scientist at the University of Washington.
The surge may last six weeks to eight weeks. That is longer than it takes adults in intense malaria areas, where people get the parasitic disease once or twice a year, to recover from a typical bout and feel up to sexual activity again, he said.
Moreover, HIV patients are more susceptible to malaria reinfection because of their weakened immune systems.
Armed with that information, Abu-Raddad turned to parts of Africa , a region w here he found good data tracking HIV and malaria prevalence over decades, and even information on sexual behaviour such as average number of partners and volume of sex workers.
In regions where both diseases are common, malaria may be responsible for almost five per cent of HIV infections, and HIV may be behind 10 per cent of malaria episodes. In Africa , that translated into 8,500 extra HIV infections and 980,000 extra malaria bouts over two decades, he concluded.
© The Calgary Herald 2006
Malaria helps spread AIDS: studyNew research suggests malaria may be helping to spread the AIDS virus across Africa.
Scientists in the US and Africa say the diseases are likely to spread more quickly when they interact.
Researchers studying the rapid spread of HIV/AIDS in one region of Africa were puzzled when risky sexual behaviour was not in itself sufficient to explain the rate of transmission.
Their research, based in on the Various towns shores of Lake Regions, led them to look at the interaction of AIDS and malaria.
The scientists concluded that when people with HIV are attacked by the malaria parasite, the HIV viral load in their bodies increases, raising the risk that the virus will be passed on.
Dr James Kublin says that at the same time, people with HIV are more susceptible to malarial infection because of their weakened immune systems.
"At times, this seems like a significant complication in efforts to control either of these," he said.
"I'm even more inclined to look at it as an opportunity in which we can better focus our efforts on the direction of how to strategically address these two scourges."
The research has been published in the American Science journal.