A Cure for Africa's Common Cold Why Malaria Persists

Over the long course of human history, no infectious disease killed more people than malaria. Called the “mother of fevers” by the ancient Chinese, malaria has plagued us since we evolved from apes and it once affected the better part of the globe. By the turn of the twentieth century, thanks to a combination of industrialization, urbanization, and agricultural development in the temperate world, the disease had been corralled into the impoverished tropics. To this day, despite a $2-billion-a-year global campaign, the mosquito-borne disease still infects some 300 million people a year
in those parts of the world and causes over half a million deaths, most of them among children and pregnant women. The story of malaria is inseparable from the history of poverty. The conditions of poverty heighten the risk of malaria infection; the disease slows GDP growth in affected societies by 1.3 percent every year, according to a study by the economist Jeffrey Sachs. Getting rid of this one disease could simultaneously slash mortality rates and inhibit a major drain on economic growth. That is why the effort to eradicate malaria has tantalized development experts for years. It sounds like low-hanging fruit, as the scientific community has known how to prevent malaria since 1897 and how to cure it since the 1600s. In fact, malaria is anything but, because of a complex interplay of political, biological, and cultural factors.
The main challenge is coalescing political will to do the job. Despite its tremendous burden on affected societies, malaria, in the most heavily infected places, is considered a “relatively minor malady,” in the words of a 2003 World Health Organization (WHO) report. That might seem counterintuitive, but it is a matter of simple risk perception. In places such as Malawi, where the average rural villager receives hundreds of bites from malaria-infected mosquitoes a year, a child might suffer 12 episodes of malaria before the age of two. If she survives, she will keep getting malaria throughout her life, but, thanks to the immunity acquired through continuous exposure, she is much less likely to die of it. For her and millions of other adults in sub-Saharan Africa’s malaria-ridden heartland, the disease becomes something that comes and goes on its own.
Much of the world’s malaria, therefore, occurs in individuals with a degree of acquired immunity and is never diagnosed or treated -- or, for that matter, formally counted. These cases are tolerated and forgotten, the way yearly bouts of cold and flu are dealt with in the West. What that means politically is that people who suffer the highest burden of malaria, such as those in countries in sub-Saharan Africa, tend to be the least motivated to do much of anything about it. They do not run to get diagnosed and treated as soon as they fall ill. They do not always bother sleeping under anti-malarial bed nets. Most important, they do not pressure their leaders or protest in the streets about the ongoing burden of malaria. As a result, in the absence of economic development, there is little political will within malaria-infected countries to take on the disease.

Much of the world’s malaria occurs in individuals with a degree of acquired immunity and is never diagnosed or treated -- or, for that matter, formally counted.

This political conundrum leads to a financial one. Because of the lack of domestic political will, most concerted attempts to address malaria have been financed by external donors from unaffected countries, as part of foreign aid and charitable programs. These efforts, which include disseminating insecticides that can repel and kill mosquitoes and distributing anti-malaria drugs, are not technically difficult and can dramatically reduce malaria, at least for a spell. But sustaining these gains over time is a different story. The real challenge is bringing malaria cases down to zero and keeping them there long enough so that every last parasite hiding undetected in someone’s liver (as malaria parasites are wont to do) and inside every mosquito dies out. But the period of effectiveness of insecticides is directly related to how intensely they are used: the more drugs and chemicals thrown against the disease, the faster the mosquitoes and the parasites evolve resistance. The problem is not insurmountable; new drugs and insecticides, or combinations of them, can be applied. But managing resistance is time-consuming and expensive, and to work, it has to be done in a thoughtful and coordinated way. Otherwise, it can prove counterproductive. Historically, donor-funded campaigns against malaria have failed to overcome this critical hurdle. In the 1950s, the United States, as part of a larger Cold War effort to win the hearts and minds of people in nonaligned countries, financed an international campaign to eradicate malaria using the first modern synthetic insecticide, DDT. Although it initially succeeded in dramatically reducing malaria cases, the project confronted inevitably rising rates of drug and insecticide resistance, which sapped the political will to sustain external financing. To secure initial funding, campaign advocates had promised a quick victory. Instead, the battle would be long, tricky, and expensive.
The prospects for beating malaria quickly diminished. Public enthusiasm about DDT crashed after the publication of Rachel Carson’s Silent Spring, which exposed the perils of overusing DDT and similar compounds, and the chemical industry’s abandonment of off-patent DDT in favor of more lucrative, proprietary chemicals. And so, instead of renewing and intensifying the battle to fight the endgame, U.S. congressional funding was allowed to expire in 1963 -- and with it, the anti-malaria campaign. Malaria had been removed from its most tenuously held turf, in wealthy countries and island-nations, but remained deeply ensconced in its heartland from sub-Saharan Africa to Asia and Latin America, its powers of regeneration fully intact, and often in more difficult-to-control forms. A WHO expert later called the failed campaign “one of the greatest mistakes ever made in public health.”
But in 1998, the WHO, with the support of influential advocates such as Microsoft founder Bill Gates and Sachs, launched a new international effort against malaria. Donors spoke enthusiastically of eliminating the disease country by country and eventually eradicating it altogether within their lifetimes. External financing, in large part from the public-private partnership the Global Fund to Fight AIDS, Tuberculosis and Malaria, grew from less than $100 million in 1998 to $1.84 billion in 2012. In recent years, hundreds of millions of anti-malarial mosquito bed nets have been distributed across the malaria-infected world, along with cavalcades of anti-malarial drugs and diagnostic kits.
As a result, since 2000, malaria mortality has fallen by 25 percent. But, as with the earlier campaign, the decline is primarily on the fringes of the most infected areas. Fifty countries have reduced their malaria incidence by 75 percent, but together they account for just three percent of global malaria cases. In places such as Malawi, despite the increase in donor-financed efforts against malaria, the rate of the disease’s transmission has not budged. Meanwhile, resistance to current drugs has been reported in at least four countries in Southeast Asia, and resistance to insecticides in 64 countries. Once again, the fight enters its most critical phase: attacking the hardest-hit spots, such as Congo, Malawi, and Nigeria, while maintaining gains made elsewhere despite the rise of drug and insecticide resistance.
Will external financing be sufficient to finish the difficult battle this time? Since 1998, the situation for external donors has changed dramatically on the heels of the global economic recession. Facing budget shortfalls, the Global Fund announced in 2011 the cancellation of an entire round of grants. Governments everywhere have cut back on their largess to the developing world. Private-donor financing for malaria is expected to decline. Even at its peak of $2.3 billion in 2011, overall funding for the global campaign was little more than half of the $5.1 billion a year that the WHO asserted was truly needed for the job.
History is now on the verge of repeating itself. Take the case of Sri Lanka. In 1953, it reported 91,990 cases of malaria. The U.S.-led malaria eradication campaign reduced that caseload to just 17 in 1963. But then the campaign ended. Within four years, a massive malaria epidemic broke out, infecting 1.5 million Sri Lankans between 1967 and 1968. The latest effort against malaria made similarly dramatic gains in Sri Lanka. Thanks to external financing from the Global Fund, the country has brought the caseload down from more than 250,000 confirmed infections in 1999 to just 175 by 2011. Such remarkable gains are nevertheless exceedingly fragile. Without continued support from donors, Sri Lanka will almost certainly face a resurgence of the disease.
For the last several years, the Global Fund has been supporting Sri Lanka’s anti-malaria effort with tens of millions of dollars a year. But the country could soon lose that aid. The Global Fund rates the performance of its grantees according to a four-level scale, the lowest of which is “unacceptable.” Several of Sri Lanka’s performance ratings have fallen to the third level, just one up from what the Global Fund considers unacceptable -- and unfundable. Sri Lanka’s current Global Fund grants expire at the end of 2014.
A few weeks ago, the Roll Back Malaria Partnership, the alliance that includes the WHO, the Global Fund, and more than 500 partners and that coordinates the global anti-malaria campaign, released a report that seemed to recognize the increasing futility of attacking malaria this way. “Current strategies for malaria control need to continue,” the report noted, but “they alone are unlikely to lead to sustained control and elimination in the countries with the highest malaria burden.” Instead, the same things are needed that shut malaria out of the temperate world all those years ago: more people living in ways that permanently protect them from the bites of mosquitoes, in well-built, screened homes with access to electricity and graded roads. In sum: economic development.
There is a cruel irony to this reversal in the fortunes of the malaria fight. The donor-driven campaign against malaria gained momentum by arguing that attacking the disease would spur development. Now, it seems advocates are saying that the opposite may be true: development is required to attack malaria.