Illuminating the Prevalence of Trypanosoma brucei s.l. in Glossina Using LAMP as a Tool for Xenomonitoring

PLoS Negl Trop Dis. 2016 Feb 18;10(2):e0004441. doi: 10.1371/journal.pntd.0004441. eCollection 2016 Feb.

Abstract

Background: As the reality of eliminating human African trypanosomiasis (HAT) by 2020 draws closer, the need to detect and identify the remaining areas of transmission increases. Here, we have explored the feasibility of using commercially available LAMP kits, designed to detect the Trypanozoon group of trypanosomes, as a xenomonitoring tool to screen tsetse flies for trypanosomes to be used in future epidemiological surveys.

Methods and findings: The DNA extraction method was simplified and worked with the LAMP kits to detect a single positive fly when pooled with 19 negative flies, and the absolute lowest limit of detection that the kits were able to work at was the equivalent of 0.1 trypanosome per ml. The DNA from Trypanosoma brucei brucei could be detected six days after the fly had taken a blood meal containing dead trypanosomes, and when confronted with a range of non-target species, from both laboratory-reared flies and wild-caught flies, the kits showed no evidence of cross-reacting.

Conclusion: We have shown that it is possible to use a simplified DNA extraction method in conjunction with the pooling of tsetse flies to decrease the time it would take to screen large numbers of flies for the presence of Trypanozoon trypanosomes. The use of commercially-available LAMP kits provides a reliable and highly sensitive tool for xenomonitoring and identifying potential sleeping sickness transmission sites.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Humans
  • Insect Vectors / parasitology*
  • Nucleic Acid Amplification Techniques / methods*
  • Trypanosoma brucei brucei / genetics
  • Trypanosoma brucei brucei / isolation & purification*
  • Trypanosomiasis, African / parasitology*
  • Trypanosomiasis, African / transmission
  • Tsetse Flies / parasitology*

Grants and funding

The wild caught flies were collected as part of a larger project funded by the Bill and Melinda Gates Foundation (OPP1104516). LJC is funded by a LSTM PhD scholarship SJT is supported by the Biotechnology and Biological Sciences Research Council, the Department for international Development, The Economic & Social Science Research Council, The Natural Environment Research Council and the Defence Science and Technology Laboratory, under the Zoonosis and Emerging and Livestock Systems (ZELS) programme (Grant no. BB/L019035/1) and WHO-TDR. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.