A real-time PCR-based assay for detection of Wuchereria bancrofti DNA in blood and mosquitoes.

We developed and evaluated real-time polymerase chain reaction (PCR) assays for detecting Wuchereria bancrofti DNA in human blood and in mosquitoes. An assay based on detection of the W. bancrofti "LDR" repeat DNA sequence was more sensitive than an assay for Wolbachia 16S rDNA. The LDR-based assay was sensitive for detecting microfilarial DNA on dried membrane filters or on filter paper. We also compared real-time PCR with conventional PCR (C-PCR) for detecting W. bancrofti DNA in mosquito samples collected in endemic areas in Egypt and Papua New Guinea. Although the two methods had comparable sensitivity for detecting filarial DNA in reference samples, real-time PCR was more sensitive than C-PCR in practice with field samples. Other advantages of real-time PCR include its high-throughput capacity and decreased risk of cross-contamination between test samples. We believe that real-time PCR has great potential as a tool for monitoring progress in large-scale filariasis elimination programs.