Africa

The continent of Africa has been malarious for at least as long as it has been populated by humans. Vivax malaria, one of the oldest human malarias, was shut out of Africa when the gene that prevented vivax infection spread across the continent (Duffy factor). (Vivax remains rare on the continent.) In the vacuum, falciparum malaria, the most virulent and deadly malaria, emerged in Africa, carried by species of Anopheles mosquitoes such as Anopheles gambiae specifically adapted to prey on human settlements.

Historically African communities in malarial areas have practiced numerous malaria control activities, although they may not have been considered as such. Traditional knowledge of mosquito transmission of the disease probably dates back to antiquity. Avoidance of mosquito-ridden areas, undergirded by myth and ritual, was probably widespread. Traditional healers dispensed plants and herbs with antimalarial properties. The human body, too, responded to the onslaught of parasites within it, devising novel genetic changes that helped it fend off the pathogen.

Nevertheless, the parasite exacted its pounds of flesh. Plasmodium falciparum doesn’t rely on a single strategy to attack red blood cells, as its cousin Plasmodium vivax does. It has multiple strategies, and novel ways of eluding its victim’s immune system, making it the most virulent and deadly malaria of humans.

Falciparum strikes at the earliest possible moment, preying on fetuses still in the womb. Those that survive slowly acquire a fleeting and partial immunity to local strains of falciparum. But the parasite is deadly for those who lack such immunity: namely, very young children (and the women in whose wombs they develop) and outsiders. The partnership between plasmodium falciparum and anopheles gambiae make the ecology of malaria in Africa especially forbidding. In heavily infested areas, people are subject to hundreds of mosquito bites every night, and hundreds of infected bites a year. For years, falciparum protected the continent from the intrusion of outsiders (as the saying goes, Africa was protected by both hazo and tazo—forest and fever.) In 1841, for example, Thomas Fowell Buxton and a party of 159 other British sailed three steamers up the Niger river. Within months of their departure, malaria had infected over 80 percent of the expedition. By the end, one third were dead. (Adults who live in endemic malarial areas, in contrast, almost never die of falciparum.)

Falciparum’s effect on foreigners shaped Africa’s reputation in Europe. The British in particular equated climate with health – and health with morality – and so many interpreted falciparum’s ferocity toward them as suggestive of something malignant about the place itself, spawning a mythology of the “heart of darkness” that persists to this day.

European colonization of Africa was relatively brief, and save for temperate South Africa, never resulted in widespread settlement. Nevertheless, the business of building European empires in Africa disrupted traditional antimalarial practices in ways that likely intensified malaria transmission in many places. Colonial regimes extracted tax payments, cut down ritually dangerous forests, condemned local healers and resettled locals on long taboo mosquito-ridden river valleys to dig for minerals. Many Africans, writes historian Steven Feierman, “saw the colonialists… as engaging in biological warfare.”

When European powers put their own malaria control programs in place in their African colonies, they opted for methods that largely excluded local people. By 1900, European scientists had established that drainage, mosquito netting, window screening, and larviciding protected people from malaria. British antimalarial policy in Africa in contrast was to segregate Europeans from the malarious Africans. According to the office of British Colonial Secretary Joseph Chamberlain “the question that is of the most urgent necessity…is not so much how large towns with sometimes 40,000 native inhabitants can be freed from Anopheles, but how the comparatively small number…of Europeans can be protected.” Chamberlain sent confidential letters to the governors of all the British colonies in Africa. “All new buildings,” he decreed, should be “located away from native quarters.”

Sub-saharan Africa was similarly excluded from the “global” malaria eradication campaign launched by the World Health Organization in the 1950s. (The rationale being that most African countries didn’t have the infrastructure necessary to support the antimalarial campaign.) A “pre-eradication” campaign was started in Africa, but was later abandoned. The United States, in the mid-1960s, explicitly outlined its intent not to aid African countries. President Johnson’s mandate to the State Department, according to a national security council staffer, “cautions that substantial increases in U.S. foreign assistance expenditures [to Africa] are not envisaged.” Instead, riven by growing debt, international funders such as the IMF and World Bank, imposed structural adjustment programs on poor, indebted African countries, under which nascent basic services such as electricity, health care facilities, schools, road works, and sanitation crumbled. Malaria, historically a rural disease, started to break out in African cities in the 1980s, as vegetation started to grow in the cracked concrete of urban slums, and residents were forced to set out their empty vats and bins to collect rainwater. A 1988 flood in the city of Khartoum set off a malaria outbreak, with more than 25,000 cases. By the 1990s, malaria had spread into urban slums throughout Africa, including Khartoum and Nairobi.

As malaria’s death toll in Africa climbed, a coalition of international organizations launched an antimalarial campaign aimed at Africa in 1998. This time, it wouldn’t be just the WHO and local governments, but a whole host of partners, from ExxonMobil to the chemical giant Bayer, banded together to “Roll Back Malaria.” By 2005, the campaign planned to ensure that 60 percent of all malarial victims in Africa were treated; that 60 percent of those threatened by the parasite—some 600 million—were protected from malarial mosquito bites; and that 60 percent of all pregnant women in malarial areas receive anti-malarial preventive treatment. Bettering the United Nation’s Millenium Development Goals, by 2010 the Roll Back Malaria campaign would slash the malarial death toll in Africa by half.

Along with prompt treatment of cases and sophisticated surveillance to predict and contain epidemics, the centerpiece of the program was on what economist Jeffrey Sachs touted as a “quick win”: distribution of insecticide-soaked bednets. The treated nets repel mosquitoes, and kill those that land on it. Hung over beds and sleeping mats, the treated nets slash child mortality in malarial areas by some 20 percent.

Critics noted that the strategy relied heavily on a single technology product—the chemical-laden net—and as such was less a control strategy than a gesture. Numerous studies showed that even when nets were successfully distributed, they were often not used, or not used appropriately. In addition, the insecticides used on the nets—pyrethroids—had long been used in African agriculture. Anopheles gambiae that had grown insensitive to the killing action of pyrethroids had been recorded in 1993: five years before Roll Back Malaria launched its program. The treated nets still worked to repel mosquitoes, for insensitive mosquitoes obliviously rested on the nets for longer periods of time, and the higher doses eventually knocked them off.

By 2005, the Roll Back Malaria campaign had resulted in 4.7 million insecticide-treated nets in use in Africa (the stated goal was to have 600 million nets in use by 2010.) That year, a study conducted by scientists from Cameroon found that malarial mosquitoes infected just as many people who slept under insecticide-treated nets as those who slept under untreated ones (widely available in local markets throughout Africa). Mosquito resistance to pyrethroids had proceeded to the extent that exposure to the insecticide made no difference to the insects. Recently, with the natural resources of Africa increasingly attractive to industrial powers, both the United States and China have launched ambitious anti-malaria programs in African countries. The new American program, the President’s Malaria Initiative, incorporates indoor house spraying with DDT and other American-made insecticides. The Chinese programs, in contrast, rely heavily on treatments based on artemisinin, which was developed by Chinese scientists. Both have claimed successes, albeit limited.

Sustainable malaria control, of course, requires local governance and funding. With traditional ways disrupted and modern infrastructure limited, few African governments in malarial regions of Africa have been able to sustain effective malaria control. In contrast to the West, where malaria is seen as a deadly killer (which it is for most Westerners), in much of Africa, malaria is considered a normal part of everyday life. After all, the vast majority of malaria in endemic areas of Africa are virtually asymptomatic. In heavily malarial countries such as Cameroon, more than 90 percent of the population is infected with malaria parasites, but their acquired immunity prevents them from falling ill. Most symptomatic cases are not rushed to hospitals and clinics, but treated at home, with local remedies or drugs purchased from nearby vendors.

The ubiquity of malaria, and its disproportionate burden on the youngest, thus acts to dissipate political will to counter it, and yet its burden continues to be high. The majority of deaths from malaria worldwide occur in sub-Saharan Africa, where malaria has been estimated to constrict economies by over 1 percent every year. Historically when malaria transmission has been disrupted, all-cause mortality has fallen.

For more:

Sir Malcolm Watson, African Highway: the battle for health in Central Africa (London: John Murray, 1953)

Gordon Harrison, Mosquitoes, Malaria and Man: A history of the hostilities since 1880 (New York: E.P. Dutton, 1978)

Socrates Litsios, The Tomorrow of Malaria (Wellington, NZ: Pacific Press, 1996)

Philip D. Curtin, Disease and Empire: the health of European troops in the conquest of Africa (Cambridge: Cambridge University Press, 1998)

H. Kristian Heggenhougen et al, The Behavioural and Social Aspects of Malaria and its Control (UNDP: Special Programme for Research & Training in Tropical Diseases, 2003)

Prominent NGOs focused on malaria in Africa:

Multilateral Initiative on Malaria
http://www.mimalaria.org/eng/

Medicines for Malaria Venture
http://www.mmv.org

European Malaria Vaccines Initiative
http://www.emvi.org/

African Medical and Research Foundation
http://www.amref.org/

Roll Back Malaria: Malaria in Africa
http://www.rbm.who.int/cmc_upload/0/000/015/370/RBMInfosheet_3.htm

Malaria No More
http://www.malarianomore.org/?gclid=CIz9lsiH2o8CFQZxHgodhjO12g

The President’s Malaria Initiative
http://www.fightingmalaria.gov/

“The re-emergence of the malaria threat is…a major challenge to the global economy.” —Nature Biotechnology