Net loss: Insecticidal bed nets, used to protect against mosquitoes, are not reaching Africans. Credit: ALEXANDER JOE/AFP/Getty Images

In the fight against malaria, long-lasting insecticidal bed nets—made from polyester or plastic and treated with insecticides—are a favorite tool. Because they can be washed and reused for years, donors such as the Roll Back Malaria Partnership push for their use.

But the nets are not blanketing Africa as efficiently as they could, thanks to a bottleneck of sluggish evaluation at the World Health Organization (WHO), says Africa Fighting Malaria (AFM), a South African advocacy organization. Best known for supporting the indoor spraying of the controversial pesticide DDT, AFM on 23 April released a report on the WHO's Pesticide Evaluation Scheme (WHOPES).

WHOPES can take up to two years, beginning with the lab and moving to small-scale field trials, at which point nets earn an interim recommendation. A multiyear field trial that also rates community acceptance is needed for final approval.

This is an artificial obstacle that has been created by a whole range of interests. David McGuire, Academy for Educational Development

Most available bed nets are made either by Tokyo-based Sumitomo Chemical, makers of the fully recommended polyethylene Olyset, or the Swiss firm Vestergaard Frandsen, manufacturers of interim-recommended PermaNet, by far the most popular long-lasting insecticidal net. Several others, including an earlier version of PermaNet, failed to win the WHO's approval.

Basel-based Syngenta and several others are waiting for approval for their nets, and a product from BASF, the German chemical giant, gained interim approval in December 2006.

Because many governments and donor groups only buy WHOPES-recommended nets, the lengthy process of evaluation is stifling competition and handicapping the fight against malaria, says Philip Coticelli, AFM's research and communications manager. “I think it has real implications in cost effectiveness and use of public funds going back years,” he says.

AFM recommends that the evaluation time be cut down to six months, in part by making some decisions outside the organization's annual meetings. “WHOPES should meet more than once a year or join the twenty-first century and hold teleconferences when data are ready for review,” Coticelli says.

Not surprisingly, the WHO maintains that the evaluation time is necessary to assure quality and a six-month timeframe is unrealistic. The AFM's position “ignores not only the time needed for testing and evaluation of the product in accordance with the Guidelines, but also fails to consider the time needed for the conclusion of agreements with research institutions; for obtaining relevant national and ethical clearances; for the payment by industry of the cost of the testing and evaluation process and last but not least, for the provision of the testing material,” the organization said in a statement.

Other critics don't place the blame on the WHO, but agree with the AFM that the delays are onerous for Africans, keeping prices high and reducing access.

“This is an artificial obstacle that has been created by a whole range of interests,” says David McGuire, director of the center for private sector health initiatives at the Academy for Educational Development, which uses US funds to encourage net use in Africa and boost local businesses making nets. “It doesn't make public health sense.”

With improvements in technology over the past four years, malaria donors have shifted their focus to long-lasting insecticidal bed nets, creating a rush for companies trying to enter the market, says Pierre F. Guillet, WHO's Global Malaria Program Coordinator for Vector Control and Prevention. “The problem is that everyone was jumping on these nets, and industry moved very quickly. Long-lasting insecticidal nets moved from 20% of the total demand for bed nets to 80% in one year—2004,” Guillet says.

Meanwhile, public requests for bids put out by governments and organizations sometimes seem to be tailor-written for PermaNet.

“It is true that a number of programs or institutional buyers, based on technical information in the scientific community, decided that they wanted only one of these technologies, and it has tended to create a kind of monopoly,” says Guillet. “But I think that this is more or less a thing of the past.”