Doctors and vampires in sub-Saharan Africa: ethical challenges in clinical trial research.

Collecting blood samples from individuals recruited into clinical research projects in sub-Saharan Africa can be challenging. Strikingly, one of the reasons for participant reticence is the occurrence of local rumors surrounding "blood stealing" or "blood selling." Such fears can potentially have dire effects on the success of research projects--for example, high dropout rates that would invalidate the trial's results--and have ethical implications related to cultural sensitivity and informed consent. Though commonly considered as a manifestation of the local population's ignorance, these rumors represent a social diagnosis and a logical attempt to make sense of sickness and health. Born from historical antecedents, they reflect implicit contemporary structural inequalities and the social distance between communities and public health institutions. We aim at illustrating the underlying logic governing patients' fear and argue that the management of these beliefs should become an intrinsic component of clinical research.

Medical syncretism with reference to malaria in a Tanzanian community.

What happens when new health information is introduced into a community? We have explored this question in a semi-rural community of Southeastern Tanzania whose population has been in contact with biomedicine for many decades. With the example of malaria, we illustrate how biomedical knowledge transmitted in health messages coexists, interacts and merges with local pre-existing ideas and logics. The results are syncretic models, which may deviate considerably from what health promoters intended to transmit. Some of those may have implications for treatment of malaria, which may include delay in seeking treatment and non-compliance with therapy. Analysing this medical syncretism clearly demonstrates that even if comprehension of health messages is accurate, the way in which people interpret these messages may not be. Disentangling syncretic processes permits us to understand the dynamics of how information is processed by the recipients, and provides orientations for health promoters for adapting messages to the local context.