“FREE goods are worth what you pay for them” is the cynic's approach to the world, shared by hard-headed poverty-busters. Charging even a nominal price for things such as mosquito nets and condoms makes people take them more seriously, it is argued. Given away free, the nets may end up being used to catch fish rather than protecting sleeping people.

That does happen. Even so, a recent study in Kenya suggested providing malarial areas with large numbers of free bed nets brought better results than selling them. Now a new survey carried out by the World Health Organisation (WHO) on behalf of the Global Fund to Fight AIDS, Malaria and Tuberculosis, which is to be published on Friday February 1st, has shown that the approach works well in other countries, too.

Unlike most big do-gooding outfits, the Global Fund is flexible and iconoclastic. It was one of the first international aid organisations to come up with the radical idea of seeing whether its interventions actually work. Since it consists of a small secretariat in Geneva and a few local offices, it lacks the scientific and managerial infrastructure to do this itself. So it subcontracts the job—in this case to Arata Kochi, the head of WHO's anti-malaria operation.

Dr Kochi and his team reviewed antimalaria operations in Ethiopia, Ghana, Rwanda and Zambia, looking mainly at under-fives, who are most threatened by the disease. WHO says that over 1m people die each year of malaria, mostly in Africa. In Ethiopia, the amount of childhood malaria reported at clinics fell by 60% and the death rate halved within two years of the beginning of the mass-distribution programme. In Rwanda, things were even more spectacular: both cases and deaths dropped by two-thirds within a single year. In Zambia the fall in both was around a third. Only in Ghana were the data equivocal. Cases fell by an eighth and deaths by a third, but that was against a background of generally improving health in which the amelioration rates for malaria were worse than those for non-malarial illness and death. In other countries, the rate of malaria tracked the general disease rate until the programmes began, and then fell suddenly (see chart).

Giving away insecticide-impregnated nets free to anyone visiting a clinic (the nets stay potent for about five years) was not the only new thing about the operations. In all cases, the countries rolled out nationwide campaigns instead of relying on local ones. In many cases, they also gave away drugs based on artemisinin, a substance to which the malarial parasite has yet to develop widespread resistance.

Nets and artemisinin are two planks of malaria control. The third is to spray the inside of people's houses with DDT, to kill female mosquitoes when they settle to digest their blood meals. The objective is to achieve 80% take-up in each village. At that point, the cycle of transmission from mosquito to human to mosquito is broken in a way similar to the action of a vaccine; this stops the spread of the disease, and thus protects everyone.

Based on the new results, Dr Kochi reckons that a five-year campaign costing about $10 billion would be enough to bring malaria under control in most of Africa, reducing the death rate to a matter of thousands a year.

Eliminating malaria altogether, though, would be a far harder task, involving destroying mosquitoes in the remaining pockets of infection. That is controversial: some—not least Dr Kochi—see it as a dangerous distraction until the easier job of bringing the disease under control is completed. Others want to aim straight away for elimination. In the long run, that should surely be the objective. But, as the old saying has it, the best can often turn out to be the enemy of the good. And the good now looks to be in sight.