Diagnosis &Monitoring &Treatment Bill Brieger | 11 Jul 2010 09:08 am
dengue, chikungunya, malaria and more
Not all fevers are malaria. This should not be an earth shaking statement, but national treatment guidelines in malaria endemic countries often stress presumptive treatment for malaria, especially when children present with fever. Irin explains that even the World Health Organization has been hard pressed to recommend otherwise when accurate parasitological diagnostic resources are unavailable.
The concern about over-diagnosis of malaria is hitting home though because the current first line treatment, artemisinin-based combination therapy (ACT) is quite expensive, and additionally, health experts are concerned that overuse or misuse of these drugs may foster parasite resistance. To make this point even stronger Peter Gething and colleagues found that, “Of the 183 million children with malaria symptoms treated by public health clinics in 2007, only 43 percent were diagnosed with malaria, but many more most likely received anti-malarial medication (IRIN News).”
A variety of febrile illnesses, especially from mosquito-borne diseases, occur in the same community. A news report from Vapi, India states that, “During the (previous week), 13 cases of chikungunya, six of dengue and 25 of malaria have been reported from in and around Vapi with Nehru Street being the most affected. The outbreak of mosquito transmitted diseases has made the health officials in the district rush to the city to initiate measures for vector control.”
A serological-epidemiological household survey in Sudan after a yellow fever outbreak found, “serologic evidence of recent or prior chikungunya virus, dengue virus, West Nile virus, and Sindbis virus infections.”
Källander and colleagues stressed the challenges of clinical diagnosis to differentiate malaria and pneumonia and reported that, “Of 3671 Ugandan under-fives at 14 health centres, 30% had symptoms compatible both with malaria and pneumonia, necessitating dual treatment. Of 2944 ‘malaria’ cases, 37% also had ‘pneumonia’.”
Gething’s group did find that 72% of those febrile cases that actually were malaria were found in locations that had higher parasite prevalence. Possibly clinicians in more highly endemic areas can presume correctly more often that a fever is malaria, but this still does not stop the wastage of ACTs, which will continue until the parasitological testing gap is closed with adequate supplies of rapid diagnostic tests and microscopes (and the skills to use these).
Gething and colleagues stress the need for countries to develop appropriate strategies by adapting the statistical models they developed with more country based data. They sadly conclude that, “Unfortunately, inadequacies in national health management information systems across Africa are in part a cause of the present imperfections in essential commodity demand and burden estimation.”
It would be even sadder if much of the treatment commodity supplies distributed in 2010 to achieve universal coverage of malaria interventions were wasted on non-malaria fevers.