Deltamethrin resistance in Aedes aegypti results in treatment failure in Merida, Mexico.

• Main Authors: Gonzalo M Vazquez-Prokopec (Author), Anuar Medina-Barreiro (Author), Azael Che-Mendoza (Author), Felipe Dzul-Manzanilla (Author), Fabian Correa-Morales (Author), Guillermo Guillermo-May (Author), Wilbert Bibiano-Marín (Author), Valentín Uc-Puc (Author), Eduardo Geded-Moreno (Author), José Vadillo-Sánchez (Author), Jorge Palacio-Vargas (Author), Scott A Ritchie (Author), Audrey Lenhart (Author), Pablo Manrique-Saide (Author)
• Format: Book
• Published: Public Library of Science (PLoS), 2017-06-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 1935-2727; 1935-2735; 10.1371/journal.pntd.0005656
• Keywords: Arctic medicine. Tropical medicine; RC955-962; Public aspects of medicine; RA1-1270
• Source: PLoS Neglected Tropical Diseases, Vol 11, Iss 6, p e0005656 (2017)

The operational impact of deltamethrin resistance on the efficacy of indoor insecticide applications to control Aedes aegypti was evaluated in Merida, Mexico. A randomized controlled trial quantified the efficacy of indoor residual spraying (IRS) against adult Ae. aegypti in houses treated with either deltamethrin (to which local Ae. aegypti expressed a high degree of resistance) or bendiocarb (to which local Ae. aegypti were fully susceptible) as compared to untreated control houses. All adult Ae. aegypti infestation indices during 3 months post-spraying were significantly lower in houses treated with bendiocarb compared to untreated houses (odds ratio <0.75; incidence rate ratio < 0.65) whereas no statistically significant difference was detected between the untreated and the deltamethrin-treated houses. On average, bendiocarb spraying reduced Ae. aegypti abundance by 60% during a 3-month period. Results demonstrate that vector control efficacy can be significantly compromised when the insecticide resistance status of Ae. aegypti populations is not taken into consideration.