The Vector Population Monitoring Tool (VPMT): High-Throughput DNA-Based Diagnostics for the Monitoring of Mosquito Vector Populations

Abstract

Regular monitoring of mosquito vector populations is an integral component of most vector control programmes. Contemporary data on mosquito species composition, infection status, and resistance to insecticides are a prerequisite for effective intervention. For this purpose we, with funding from the Innovative Vector Control Consortium (IVCC), have developed a suite of high-throughput assays based on a single “closed-tube” platform that collectively comprise the “Vector Population Monitoring Tool” (VPMT). The VPMT can be used to screen mosquito disease vector populations for a number of traits including Anopheles gambiae s.l. and Anopheles funestus species identification, detection of infection with Plasmodium parasites, and identification of insecticide resistance mechanisms. In this paper we focus on the Anopheles-specific assays that comprise the VPMT and include details of a new assay for resistance todieldrin Rdl detection. The application of these tools, general and specific guidelines on their use based on field testing in Africa, and plans for further development are discussed.

Can malaria vector control accelerate the interruption of lymphatic filariasis transmission in Africa; capturing a window of opportunity?

“…Alarmingly, almost all of the 17 countries have already reported some degree of insecticide resistance to one of the main classes of insecticides, in one of the main Anopheles species responsible for malaria transmission. The scope of this problem is yet to be fully determined, however, resistance monitoring is becoming increasingly important among international stakeholders such as PMI [41], and the development of publicly accessible up-to-date databases and maps, including the new IR Mapper [67,68], will help to assess the situation over time and space along with other programmatic activities [69-71]. This is particularly important given the limited availability of vector control tools and the fact that new products will not be available for some years [72].…”

Malaria transmission after five years of vector control on Bioko Island, Equatorial Guinea

“…[15] using slightly modified PCR conditions. Detection of the knock-down resistance alleles L1014F and L1014S (previously referred to as kdr- west and kdr- east, respectively), as well as the insensitive acetylcholinesterase ( iAChE ) allele was performed using the real-time Taqman assays developed by Bass et al [16,17]. …”

Insecticide Resistance Allele Frequencies in Anopheles gambiae before and after Anti-Vector Interventions in Continental Equatorial Guinea

“…6 The ace-1 R allelic discrimination assay described by Bass and others was used to screen for susceptible (ace-1 S ) or resistant (ace-1 R ) alleles, with minor modifications (5 μL of DNA template was used per reaction). 41 Homozygous susceptible and resistant ace-1 plasmid controls were used as controls. Heterozygous controls were created by mixing equimolar amounts of homozygous resistant and susceptible plasmid DNA.…”

“…38,39 To determine the presence of kdr and ace-1 R alleles, allelic discrimination assays described by Bass and others were performed with an ABI 7500 Fast quantitative PCR instrument (Applied Biosystems, Foster City, CA). 40,41 The Sensimix II™ (Bioline USA Inc., Taunton, MA) master mixture was used for kdr and ace-1 allele detection assays. TaqMan MGB™ was obtained from Applied Biosystems.…”