Identifying genes putatively conferring insecticide resistance in the Chagas vector Triatoma infestans

Jon Tomkinson

American trypanosomiasis is a potentially life threatening illness commonly known as Chagas disease, caused by a protozoan parasite Trypanosoma cruzi. This life debilitating and potentially deadly disease affects millions of people in the Southern Cone countries of South America and has no vaccine or cure.

Triatoma infestans drawn by Thom Dallimore

The T. cruzi parasite is transmitted by insect vectors known as Triatomine bugs or Assassin bugs, the most common vector of Assassin bugs is Triatoma infestans. Transmission from T. infestans usually occurs at night when the skin of the host is broken by the blood sucking insect and faeces that are left near the wound enter the host’s body carrying the parasite.

As there is no vaccination for Chagas disease, control is primarily by targeting the vector. The current most popular method to control the spread of Chagas disease is through insecticide application in domestic structures. The overuse of such insecticides such as deltamethrin and other pyrethroid compounds has led to some populations of T. infestans to become resistance to certain insecticides.

This project aims to investigate the genetic profile of these resistance traits within T. infestans, particularly the role of the enzyme superfamily cytochrome P450’s.

The work completed in this project will provide vital genetic information on the resistance profile of T. infestans to research groups, potential pesticide companies and other control programmes on how best to control the vector. This research will contribute to saving thousands of lives and improving the lives of millions more by helping to reduce the spread of Chagas disease.