Malaria: Finishing Off Relentless Global Killer

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There’s a renewed push to finally finish off one of humanity’s oldest enemies: malaria. The disease-causing parasite first appeared when modern humans replaced Neanderthals some 150,000 years ago — and the formidable enemy has outsmarted us ever since.

Malaria is caused by parasite that is injected into the human blood stream by a female mosquito. It hides in the liver, then hijacks oxygen-rich red blood cells, rupturing them and proliferating throughout the body until, overwhelmed and starved for oxygen, it breaks down. Symptoms include fever, headache and vomiting, which, if not treated, can quickly become life threatening by disrupting blood supply to vital organs.

Malaria kills between 1 million and 2 million people each year, the majority of them children in sub-Saharan Africa. In fact, child malaria deaths in Africa occur at a rate of 2,000 a day, according to the Bill & Melinda Gates Foundation, although some researchers put the number even higher.

The disease also occupies a vast territory, lurking throughout the developing world in large swaths of tropical and subtropical areas. Malaria used to be a threat in the southeastern United States through the 1950s, but in 2005, the Centers for Disease Control and Prevention reported just two cases of people infected with the disease in the United States.

Elsewhere, however, this enemy has persevered. A worldwide attempt to wipe out malaria in the 1950s used the synthetic pesticide DDT and the drug chloroquine. But according to a recent edition of the New England Journal of Medicine, the world’s first coordinated disease-eradication effort backfired, with mosquitoes and parasites turning resistant, rebounding, and new epidemics appearing.

Now, public and private organizations are trying again, armed with more money and newer research. Enlistments include the World Health Organization, World Bank and the United Nations with its disease-fighting Global Fund to combat HIV/AIDS, tuberculosis and malaria. Other contributors include U.S. military researchers and the National Institutes of Health, as well as nonprofits scattered throughout the world.

One of the most prominent and dogged fighters in the worldwide malaria battle has been the Bill & Melinda Gates Foundation and its philanthropic global health initiatives. The couple gave billion of their Microsoft fortune to their foundation, and mega-investor Warren Buffett has added another billion more.

Last fall, the visionary Gates duo called for malaria’s “eradication” — a radical approach because most mainstream scientists don’t think malaria can be eradicated; rather it can realistically be shrunk in transmission areas and treated in patients. According to a January report by the World Health Organization, “global eradication cannot … be expected with the existing tools.”The world body also noted that to lower the global malaria rate 75 percent by 2015 could cost a staggering .5 billion a year.

Undaunted, Gates — who has already remade our high-tech world —is pursuing the foundation’s agenda of eradication while at the same time funding and encouraging malaria reduction projects.

Preventative drugs do exist — the oldest is quinine — but they are expensive and most appropriate for short-term protection.There are a number of treatment drugs, with Artemisia being the most effective, and insecticides and bed nets are other important tools in the arsenal.

In 2007, the World Health Organization reported that intensive new efforts to reduce malaria in Africa had met with some success through the distribution of insecticide-soaked bed nets and patient treatments using artemisinin combination therapy (ACTs). Deaths in young children in Rwanda were decreased by 66 percent, halved in Ethiopia, and down a third in Zambia and Ghana.

However, everyone agrees that the ultimate weapon is an effective vaccine, but one doesn’t exist — yet.Worldwide there are 31 promising vaccine candidates in the uphill effort to kill malaria-carrying mosquitoes or stop the parasite itself.

Genetic tools are trying to help the human immune system pinpoint and attack the disguised parasite, and vaccine researchers hope that manipulated protein pieces of the parasite could stimulate an immune response, although so far research efforts haven’t panned out and many of the vaccines in the pipeline have been a disappointing failure.

But one local researcher is taking a rebel approach in the hunt for a vaccine with help from the Gates financial apparatus. Dr. Stephen Hoffman, founder and head of the Maryland biotechnology firm Sanaria, has eschewed tweaking DNA in favor of more old-fashioned techniques by injecting the whole malaria parasite with a sporozoite vaccine after bombarding it with rays so that it can’t cause disease. His approach has been attacked by skeptics, but the Technology Council of Maryland just named Sanaria its emerging company of the year.

Innovative researchers are also going after the malaria-bearing mosquito itself, trying to create parasite-free versions that could replace the actual bug. For instance, Laurence Zweibel of Vanderbilt University, observing that the insect depends on its sense of smell to survive, is trying to develop “odorant” compounds that will disrupt its behavior, throwing a monkey wrench into the mosquito’s life cycle.

Yet Christian Loucq, head of the Malaria Vaccine Initiative (MVI) established by the Gates Foundation, gave a grim assessment of the search for a vaccine. Speaking at a meeting last fall sponsored by Johns Hopkins University and the New YorkAcademy of Sciences, Loucq said MVI had winnowed 28 vaccine candidates to eight, but admitted that “a lot of them will fail” and that the field’s bright star only has a 50 percent success rate at best in current clinical trials — “the most disappointing development at the moment” in malaria work, he lamented.

Despite all the setbacks, Loucq, like his colleagues, remains passionate. “The return on our investments is going to be counted in lives saved.”

It’s that type of optimism that keeps driving people like Bill Gates, who late last month officially stepped down from his full-time role at the company he founded to focus on his philanthropic work. “Today governments, aid groups and communities are simply refusing to accept the notion that diseases like malaria and tuberculosis will haunt us forever,” Gates recently wrote. “These problems can be solved.”

About the Author

Carolyn Cosmos is a contributing writer for The Washington Diplomat.

Last Edited on November 29, 1999