RESUMO
A randomized, double-blind field trial was carried out to compare the economic impact of permethrin-treated nets with that of untreated nets as a method of malaria control. The study was conducted in 261 long-term migrant workers and 138 seasonal agricultural migrant workers in the eastern rural areas known to be highly endemic for multidrug-resistant Plasmodium falciparum infection. One hundred and twenty-six longterm migrants and 59 seasonal migrants used treated nets, while 135 and 79, respectively, used untreated nets. The impregnated-nets program was cost-saving as well as offering improved effectiveness. The net benefit of using a treated net was US$1.17 per worker from the Malaria Division's perspective and US$1.61 per worker from the worker viewpoint. The use of impregnated nets with large-scale primary health care programs likely will be the most cost-effective and cost-beneficial method for controlling malaria in eastern Thailand.