Stop ambiguous messages on malaria diagnosis

Reyburn et al's findings on malaria case management in endemic areas are worrying.1 Part of the problem is due to ambiguous messages provided by malaria experts and national guidelines on how to take action on the result of a malaria test. Undoubtedly, the ambiguity of national malaria control programme guidelines on the management of suspected malaria in children younger than 5 years is a factor.2

In Tanzania the recommendation is to perform microscopy/rapid diagnostic tests for malaria. If results are negative and there are no signs and symptoms of severe disease in a child under 5 years, treat as uncomplicated malaria and look for another condition.3 Similar inconsistency is found in the Ugandan guidelines.

The risk of missing a true malaria case in the event of a negative test and the resulting consequences have recently been evaluated thoroughly in Uganda.4 Febrile children were not given antimalarials when the results of microscopy were negative (rate of malaria test positivity: 32%). Only two malaria cases out of 2359 febrile episodes were missed; both patients consulted the next day because of persisting fever and were treated for uncomplicated malaria on the basis of new positive test results. In parallel, 464 non-malaria causes of fever in need of antibiotic treatment were identified.4

The assertion that feverish children under 5 years should be treated with antimalarials irrespective of the test result, because the disease has a more rapid course, is inadequate. The clinical assessment to identify danger signs early enough is crucial, but how well the test performs, and hence the trust we can have in its result, is the same in all age groups. Teaching material and guidelines should not be based on beliefs and fears but should be updated by using most recent evidence. In uncomplicated febrile illness a positive result in a malaria test means malaria and a negative result, no malaria.