Comparative analysis of genomic DNA amplification yield for Plasmodium falciparum extracted from urine, saliva and blood

Malaria treatment and/or management remains an essential element as well as strategy controlling this pathology. Since 2005, Cote d'Ivoire has adopted Artemisinin-based Combination Therapies (ACTs) as first-line drugs to treat uncomplicated malaria. Malaria diagnostic mechanism involves blood sampling by using finger prick collection or venipuncture which requires very strict aseptic conditions. However, some groups of people refuse to cooperate with these diagnostic methods because of (i) cultural believe forbidding seeing of blood and (ii) trauma related to the needle sting. Here, two non-invasive sampling and one invasive methods to diagnose malaria using molecular method were tried. Blood, urine and saliva samples were collected in three different localities from patients above 2 years of age having simple Plasmodium falciparum malaria confirmed by microscopy. Then, P. falciparum genomic DNA was extracted and amplified through Pfcrt, Pfdhfr-ts, and PfK13 propeller genes specific primers. Amplification products were processed by electrophoresis and analyzed according to blood, saliva and urine samples. A multivariate statistical analysis based on R software was carried out with the purpose to assess the aptitude and/or performance of each analyzed biological samples in malaria molecular diagnosis procedure. The results revealed the presence of P. falciparum DNA in urine (27.57%) of the amplification products, saliva (40.21%) and blood (91.55%). Assuming blood sample as benchmark, the statistical analysis exhibited saliva as a suitable biological sample fitting for malaria molecular diagnosis (p-value ≤ 0.05), and suspected urine as a source of variability analyzing the aforementioned described malaria patient population excluding the latter as a reliable sample in malaria molecular diagnosis. The same results exhibited Pfdhfr and PfK13 propeller genes amplified from saliva as satisfactory molecular markers for chemo-resistance. The findings suggested P. falciparum genomic DNA amplification from saliva sample as closer in comparison to blood and proposed the former (saliva) as an alternative to blood in malaria molecular diagnosis process. Key words: Molecular diagnosis, malaria, pfcrt, pfdhfr-ts, pfK13 propeller, Plasmodium falciparum, saliva, urine.