Children participating in a study evaluating the efficacy of chloroquine and amodiaquine for the treatment of malaria will, if getting malaria during follow-up, be re-treated with sulfadoxine-pyrimethamine (SP) in accordance with the recommendations of the National Malaria Programme.

To compare the actual efficacy of SP with that in 1995 - 1996 we, the investigators of the Bandim Health Project, will visit these children once a week for 5 weeks. A finger prick blood sample will be collected for a malaria test.

Children with malaria during follow-up will be treated according to the guidelines of the Bandim Health Centre.

The Bandim Health Project studies the efficacy of different treatment regimens for malaria in children. If the included children during follow-up get malaria again they are, according to the recommendations of the National Malaria Programme, treated with sulfadoxine-pyrimethamine (SP).

In 1995 - 1996 the efficacy of this re-treatment regimen was evaluated in the same area.

To evaluate if treatment with SP is still efficient we want to follow children included in a study comparing treatment with chloroquine and amodiaquine having recrudescent malaria for 35 days following the re-treatment with SP.

Children with reappearing parasitaemia will be treated with SP. If accepting to participate in this study the children will be visited once a week and a capillary blood sample will be drawn. The blood sample taken on the day of reappearing parasitaemia in the chloroquine/amodiaquine study will be used as the day 0 blood sample in the SP-study.

If the child gets malaria during the follow-up he will be treated according to the guidelines of the Bandim Health Centre. All treatment during follow-up will be free.

Inclusion Criteria:

• Malaria symptoms plus positive malaria film
• > 20 parasites per 200 leukocytes
• Treatment failure in a study comparing chloroquine and amodiaquine
• Informed consent

Exclusion Criteria:

• Stated allergy to sulfadoxine and/or pyrimethamine