Leslie and colleagues note their findings of over diagnosis of malaria in two Afghan provinces [1] is consistent with previous reports from Tanzania [2]. Unfortunately, in my experience, little has changed in Tanzania where I recently undertook voluntary work in a health centre close to a university hospital. In almost all cases when microscopy was requested for suspected cases of malaria, the patient was treated with antimalarial drugs independent of the laboratory result. This not to say that laboratory results were particularly accurate, as slides were merely glanced at with seemingly random results given; on several occasions I handed the same technician the same slide twice and it went from a very high positive result to a negative or vice versa.

There were several reasons that I observed for over diagnosis of malaria in the clinic. First, the doctors were paid more for prescribing greater numbers of antimalarial drugs: in fact one doctor who did not diagnose malaria in what was considered by the owner to be enough patients, was called up to the owner's office on several occasions, and had both his pay and work hours cut because he was not bringing in a high enough profit. Secondly, the laboratory staff were poorly trained. Three staff worked in the laboratory of whom only one had undergone training. Moreover laboratory staff received pay and extra working hours based on the number of patients they diagnosed with malaria: the only trained member of staff had the lowest number of working hours due to the low number of positives coming out of the laboratory when she was working. Lack of accurate laboratory results led, of course, to lack of trust in these results, and thus if the doctor had already decided on a clinical diagnosis of malaria, he would almost inevitably prescribe antimalarials, and laboratory tests were merely a formality used in order to bring in further profit to the health centre.

Leslie and colleagues propose several reasons why health professionals may prescribe inappropriately, but in countries such as Afghanistan and Tanzania where health workers' pay is far lower than in the UK, financial incentives to over treat should be considered.

References
1. Leslie T, Mikhail A, Mayan I, Anwar M, Bakhtash S, Nader M, Chandler C, Whitty C JM, Rowland M. Overdiagnosis and mistreatment of malaria among febrile patients at primary healthcare level in Afghanistan: observational study. BMJ 2012;345:e4389
2. Reyburn H, Mbatia R, Drakeley C, Carneiro I, Mwakasungula E, Mwerinde O, et al. Overdiagnosis of malaria in patients with severe febrile illness in Tanzania: a prospective study. BMJ 2004;329:1212.

Competing interests: None declared