Background: Targeted
malaria elimination strategies require highly sensitive tests to detect low density
malaria infections (LDMI). Commonly used methods for
malaria diagnosis such as light microscopy and
antigen-based rapid diagnostic tests (RDTs) are not sensitive enough for reliable identification of
infections with parasitaemia below 200 parasites per milliliter of blood. While targeted
malaria elimination efforts on the Thailand-Myanmar border have successfully used high sample volume ultrasensitive quantitative PCR (uPCR) to determine
malaria prevalence, the necessity for venous collection and processing of large quantities of patient blood limits the widespread tractability of this method. Methods: Here we evaluated a real-time reverse transcription PCR (RT-qPCR) method that reduces the required sample volume compared to uPCR. To do this, 304 samples collected from an active case detection program in Kayin state, Myanmar were compared using uPCR and RT-qPCR. Results: Plasmodium spp. RT-qPCR confirmed 18 of 21 uPCR Plasmodium falciparum positives, while P. falciparum specific RT-qPCR confirmed 17 of the 21 uPCR P. falciparum positives. Combining both RT-qPCR results increased the sensitivity to 100% and specificity was 95.1%. Conclusion:
Malaria detection in areas of low transmission and LDMI can benefit from the increased sensitivity of
ribosomal RNA detection by RT-PCR, especially where sample volume is limited. Isolation of high quality
RNA also allows for downstream analysis of
malaria transcripts.