The malariaproblem: Why Africa can't wait any longerfor treatment that works
Malaria is not an incurable disease, and treatment does not last a lifetime. It is curable in no more than three days. Treatment that works does exist. Why, then, are so many people in Africa dying of malaria?
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Today, in many African countries chloroquine and SP are virtually useless
Malaria is the "hidden" global scourge. And Africa is at its epicentre.
Where malaria thrives, people suffer and economies are drained. Malaria, a parasitic disease (see box page 8), thwarts children's cognitive development and education, and adults' ability to make a living and care for their families.1 At a country level, it impacts on trade, tourism and foreign direct investment. There is a remarkable correlation between malaria and poverty: average GDP in malarious countries is five times lower than in non-malarious countries.2 Malaria keeps poor people poor.
Malaria statistics read like a road map to a place where no one wants to go: 300-500 million cases a year, 90% of them in sub-Saharan Africa; 1-2 million deaths a year, mostly in Africa; US$12 billion lost every year in Africa3; 30-50% of all African hospital admissions4; and the litany goes on. Malaria is the leading killer of Africa's children.
Malaria is not an incurable disease, and treatment does not last a lifetime. It is curable in no more than three days. Treatment that works does exist. Why, then, are so many people in Africa dying of malaria? Because Africans with malaria are not benefiting from proven prevention strategies and treatment that works. Affordable, efficacious drugs are not available to them, so people continue to use older medicines that health experts know are no longer working.
No secret
There is no secret about the best treatment for malaria today. Combination therapy using artemisinin derivatives is so effective that it is bringing about a revolution in the treatment of the disease, particularly in Asia, where its use is widespread. It is time to bring artemisinin-based combination therapy, or ACT, to Africa. The World Health Organization (WHO), international donors and African governments cannot afford to let this treatment bypass the continent where malaria is taking its greatest toll.
Already bypassed once
Malaria eradication was identified as a priority in the mid-twentieth century, with the discovery in 1942 of the insecticidal properties of DDT and the establishment of the World Health Organization in 1948. The WHO-led Global Eradication of Malaria programme, launched in the 1950s, sought to eliminate the disease via vector control with DDT and through treatment with chloroquine.
Yet the campaign bypassed sub-Saharan Africa, where eradication was considered impractical because of the high level of transmission and the lack of infrastructure.5 Malaria was, however, effectively eradicated in zones where infection was lower (areas of southern Europe, North America, Mauritius and Singapore, Hong Kong, parts of Malaysia, and elsewhere). Eventually the malaria parasite developed resistance to DDT; at the same time, concerns about the pesticide's safety emerged, and the eradication strategy was dropped.
By 1969, WHO accepted the necessity of control programmes in areas where the disease was not eradicated; the focus turned to control through chloroquine treatment. For a time, this seemed to keep the disease in check, and certainly malaria mortality in Africa declined through the early 1980s (see figure 1), due in large part to the availability of cheap and effective drugs.6
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Malaria is roaring back
Now, however, malaria has roared back in Africa, spreading throughout almost all of sub-Saharan Africa. The average annual number of reported malaria cases in the period 1982-1997 is four times that reported in the period 1962-1981.7 Deaths have also increased. After a steady decline from the early 1900s to the early 1980s, the annual malaria mortality rate in Africa has jumped dramatically over the last two decades, even as that of the rest of the world has declined.8 And, since 1990, even as all-cause mortality for children has dropped in Africa, malaria-specific mortality has been on the rise.9
There has also been a recent, striking increase in the number of severe malaria epidemics on the continent, with epidemics in 35 areas between 1997-2002.10 To give just one example: between October 2000 and March 2001, a severe malaria epidemic in Burundi caused around 3 million cases among a population of 6.5 million people.11 The epidemic caused 13,000 deaths in only three provinces.
Human migration, often as a result of war or conflict, has played a role in this resurgence. People who haven't developed natural resistance to malaria increasingly migrate to regions where the disease is rife. At the same time, poverty, war and political instability have weakened public health systems in many developing countries. Changing demographics and land use have also played a part. And most experts agree that the resurgence of the disease is due in large part to that fact that malaria parasites and its vector are increasingly developing resistance to the drugs and insecticides used to control them.
The drugs are failing
In the 1950s, the drug chloroquine was first introduced to treat malaria. Fast, effective and cheap, it seemed a miracle drug, and a potent ally in the fight to eradicate the disease. But uncontrolled and widespread use contributed to the rapid emergence and spread of resistance (see box page 9) beginning in the mid-1960s, radiating out from Southeast Asia, and hitting Africa by the late 1970s.
In response, another drug, sulphadoxine-pyrimethamine (SP, also known as Fansidar®) was widely introduced, in the 1970s in Southeast Asia (starting in 1973 in Thailand) and in Africa in the early 1990s (starting in 1993 in Malawi). Initially, it was extremely useful: it is taken as a single dose, and side-effects are very uncommon. But optimism was short-lived: within five years, resistance to this drug had already developed in much of Southeast Asia, and is now spreading rapidly through Africa.
Today, in many African countries, resistance to chloroquine and SP is so high that both drugs are virtually useless. To give only a few examples: 1999 figures show 28-97% resistance to chloroquine in Tanzania, 66-87% resistance in Kenya, and 10-80% resistance in Uganda.12 According to EANMAT (East African Network for Monitoring Antimalarial Treatment), SP resistance reached 27% in Bondo and 42% in Kisumu in Kenya in 2000 and 17% in Kyela and 34% in Mkuzi in Tanzania in 1999.13 It is important to note that these data represent treatment failure detected on day seven after start of treatment. Such a short follow-up underestimates resistance compared to a longer follow-up (eg, 14 or 28 days).14 Using 14 or 28-day follow-up, MSF has documented resistance to chloroquine and SP in its medical aid projects throughout sub-Saharan Africa (see map page 6). The World Health Organization has also recognised the growing problem of drug resistance.15
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In the 1950's malaria eradication in Africa was considered impractical.
Treatment failure = more deaths
Ineffective drugs continue to be used despite the spectacular levels of resistance, leading to increased treatment failure. Treatment failure leads to rising rates of mortality, particularly among children: hospital studies in various African countries have documented a two- to three-fold increase in malaria deaths and hospital admissions for severe malaria, corresponding to the rise in chloroquine resistance.16 In Senegal, the emergence of chloroquine resistance has been directly linked to a dramatic increase in malaria mortality between 1984 and 1995 in Sahel, savannah and forest areas. This suggests that the spread of chloroquine resistance has had "a dramatic impact on the level of malaria mortality in most epidemiological contexts in tropical Africa."17
International guidelines to instruct countries in choosing appropriate malaria treatment were established in April 2001. The World Health Organization recommends that treatment failure rates should be less than 5%. Failure rates between 5 and 15% represent a warning period. Once treatment failure rises to between 16 and 24%, activities to initiate change of treatment protocol should start. And when treatment failure exceeds 25%, change is required.18
Chloroquine-resistant parasites had already been identified in all countries of tropical Africa by 1988.19 A majority of affected African countries have now reached the 25% failure rate for chloroquine and, in many places, the SP failure rate is also worsening.
International and African leaders acknowledge the crisis
This is not all happening in a vacuum, completely unnoticed. In the late 1990s, there was recognition that something had to be done to address malaria's expanding threat. Roll Back Malaria, a global partnership, was founded in 1998 by the United Nations.
Roll Back Malaria in turn convened the first-ever summit on malaria in Abuja, Nigeria, in April 2000. Senior officials from 44 affected African countries, including 19 heads of state, expressed their resolve to meet three main targets by 2005: ensure that 60% of those suffering from malaria have prompt access to correct, affordable and appropriate treatment; ensure that at least 60% of those affected by malaria benefit from suitable protective measures, such as insecticide-treated nets; and ensure that at least 60% of all pregnant women at risk for malaria receive chemoprophylaxis or presumptive intermittent treatment.20 They reiterated their commitment to the Roll Back Malaria goal of cutting African malaria deaths in half by 2010, a commitment that was echoed by the world leaders at the 2000 G8 summit in Okinawa.
In recent years, as a result of these laudable initiatives, there has been much fanfare over attempts to implement preventive measures such as provision of insecticide-treated bednets or insecticide spraying. Malaria has also been headlined for funding from the Global Fund for AIDS, Tuberculosis and Malaria. Yet so far, much of the rhetoric has not been followed up with concrete action. And, according to an external evaluation of the Roll Back Malaria partnership, in the last several years not only has there been no reduction in malaria — there may even have been an increase.21
Prevention efforts must be strengthened and commitments reinforced. Halving malaria mortality by 2010 will require that millions of people who do contract the disease each year receive treatment that works.
