Abstract

With endemic countries now aiming for elimination, the detection of malaria infections, with or without symptoms, is increasingly important for monitoring and evaluation programmes. Current malaria screening methods necessitate blood withdrawal. This invasive approach is constrained, especially for identifying the asymptomatic carrier reservoir, since segments of communities with blood taboos avoid participating. Proof of concept has previously been shown for molecular detection of malaria infection using human saliva samples. The current study optimized saliva-based malaria detection in an area of southern Zambia. Saliva pellet fractions proved a more reliable source of amplifiable parasite DNA compared to the soluble fraction. After optimizing DNA extraction and amplification, saliva-based PCR showed 94.1% sensitivity and 97% specificity, using nested PCR on blood samples as gold standard. This study demonstrates that saliva samples are a reliable non-invasive alternative to blood for the PCR detection of asymptomatic and submicroscopic malaria reservoirs.

Key words: Malaria, saliva, polymerase chain reaction.