Malaria resurges when complacency over control sets in or funding collapses, study concludes

Progress in eradicating malaria is jeopardised if programmes to combat the disease are cut, a study has concluded.

The study, published in the Malaria Journal (2012;11:122, doi:10.1186/1475-2875-11-122), looked at 75 documented cases of malaria resurgence worldwide since the 1930s. It found that in 90% of the cases resurgence was linked, in part, to weakening of malaria control programmes.

The researchers—from the Clinton Health Access Initiative; the Johns Hopkins Malaria Research Institute; the independent Center for Disease Dynamics, Economics and Policy, which is based in Washington, DC, and New Delhi; and the Global Health Group at the University of California, San Francisco—reviewed the literature to find all documented instances of malaria resurgence.

Their study looked at historical events, but its findings are relevant now after the cancellation last November of the latest funding round of the Global Fund to fight AIDS, Tuberculosis and Malaria, the biggest source of funding for malaria control worldwide (BMJ 2011;343:d7755, doi:10.1136/bmj.d7755).

Justin Cohen, the study’s lead author, said, “With the cancellation of the Global Fund’s most recent funding round coming on top of already constrained resources for global health, these results suggest that ensuring sufficient and sustained funding for malaria control and continued implementation of key interventions even once the disease is absent or low must be the utmost priority if resurgence of malaria is to be prevented.”

The study highlights the success of malaria control programmes over the past decade and the fact that the disease “has declined considerably in many previously endemic parts of the world.” However, one warning from history is the World Health Organization’s global malaria eradication programme, which began in 1955. The campaign succeeded in eliminating malaria from Europe, North America, the Caribbean and parts of Asia and South and Central America, but after its cessation in 1969 the disease took hold again.

The study warns: “Today, the threat of resurgence again looms as constrained global funding and competing priorities threaten the sustainability of successes.” It highlights brief increases in the incidence of malaria in some countries, including Rwanda and Zambia, as a matter for concern.

In Tanzania in the 1980s a project of USAID, the US overseas development agency, was terminated despite having about $1m in undisbursed funds. The incidence of malaria on the island of Pemba, in the Zanzibar archipelago, rose from 23.2% in 1989 to over 60% in 1994. After the Ethiopian government was overthrown in 1974 the application of the insecticide DDT was cut from a 1974 peak of 117 040 houses to only 8139 houses in 1985; malaria incidence rose from 1.1 cases per 1000 person years in 1980 to 65.9 per 1000 in 1989.

War, strife, or natural disaster was to blame for the cessation of programmes in two fifths of the cases, but a sense of complacency or a view that malaria was no longer a threat was to blame in a similar proportion of cases.

Cohen told the BMJ that there was a “paradox of success in global health.” He said, “Wherever malaria is successfully reduced to the level where it’s no longer filling up hospital beds and killing thousands of children, it’s likely that decision makers and donors will begin wondering, ‘Why are we still spending money on this disease that we don’t have anymore?’ But what our review demonstrates is that any weakening of the programme may result in serious resurgence.”

He added that, because donors’ priorities may change, countries should take steps to ensure that their malaria control programmes are sustainable. In Zanzibar, for example, authorities are considering levying a tax on international tourists to partly pay for malaria control.