Detection of Plasmodium falciparum and Wuchereria bancrofti infected blood samples using multiplex PCR.

ABSTRACT

A rapid and sensitive multiplex PCR has been developed for the diagnosis of multiple parasitic infection in human blood. Infection is detected by a single multiplex PCR reaction containing two pairs of oligonucleotide primers whereby each primer is specific for each parasite species. These primer sets amplified 400 and 450-bp fragments for Wuchereria bancrofti and 208-bp fragment for Plasmodium falciparum. The PCR products derived from each parasite species were visualized in ethidium bromide-stained agarose gels, therefore allowing the rapid identification of any, or all, of the two human parasites, if present, in a single amplification reaction. This multiplex PCR was very sensitive with the ability to detect the presence of as little as 10 pg of parasite DNA. The primers used in this multiplex PCR also showed highly specific amplification of each respective parasite DNA without the presence of non-specific and non-target PCR products. This multiplex PCR system was used to analyse 36 human blood samples of Myanmar workers in the endemic area at Tak Province, Thailand. Two samples showed the multiple infection, 27 samples were either infected with W. bancrofti or P. falciparum and seven samples were negative for both methods. The high sensitivity, specificity and rapidity of this multiplex PCR method make it suitable for large-scale epidemiological studies and following of drug treatment.