Resistance to Pyrethroids in the Malaria Vector Anopheles albimanus in Two Important Villages in the Soconusco Region of Chiapas, Mexico, 2022

• Published in: International journal of environmental research and public health Vol. 20; no. 5; p. 4258
• Main Authors: Solis-Santoyo, Francisco, Villarreal-Treviño, Cuauhtémoc, López-Solis, Alma D, González-Cerón, Lilia, Rodríguez-Ramos, José Cruz, Vera-Maloof, Farah Z, Danis-Lozano, Rogelio, Penilla-Navarro, Rosa Patricia
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 27-02-2023; MDPI
• Subjects: Animals; Anopheles; Anopheles albimanus; Bioassays; Carbamate pesticides; Carbamates (tradename); Cattle; Chemical control; Chlorpyrifos; Culicidae; Cytochrome P450; Cytochromes P450; Deltamethrin; Diagnostic systems; Disease transmission; Females; Gene frequency; Humans; Insecticide resistance; Insecticide Resistance - genetics; Insecticides; Insecticides - pharmacology; Livestock; Malaria; Malaria - prevention & control; Malathion; Metabolism; Mexico; Mortality; Mosquito Control - methods; Mosquito Vectors; Mosquitoes; Organophosphates; Parasites; Permethrin; Pesticides; Public health; Pyrethrins; Pyrethroids; Vector-borne diseases; Villages; Mexico; imported malaria; Anopheles albimanus; insecticide resistance; esterases; forced oviposition; pyethroids
• ISSN: 1660-4601; 1661-7827; 1660-4601
• DOI: 10.3390/ijerph20054258

Chiapas State comprises the largest malaria foci from Mexico, and 57% of the autochthonous cases in 2021, all with
infections, were reported in this State. Southern Chiapas is at constant risk of cases imported due to migratory human flow. Since chemical control of vector mosquitoes is the main entomological action implemented for the prevention and control of vector-borne diseases, this work aimed to investigate the susceptibility of
to insecticides. To this end, mosquitoes were collected in cattle in two villages in southern Chiapas in July-August 2022. Two methods were used to evaluate the susceptibility: the WHO tube bioassay and the CDC bottle bioassay. For the latter, diagnostic concentrations were calculated. The enzymatic resistance mechanisms were also analyzed. CDC diagnostic concentrations were obtained; 0.7 μg/mL deltamethrin, 12 μg/mL permethrin, 14.4 μg/mL malathion, and 2 μg/mL chlorpyrifos. Mosquitoes from Cosalapa and La Victoria were susceptible to organophosphates and to bendiocarb, but resistant to pyrethroids, with mortalities between 89% and 70% (WHO), and 88% and 78% (CDC), for deltamethrin and permethrin, respectively. High esterase levels are suggested as the resistance mechanism involved in the metabolism of pyrethroids in mosquitoes from both villages. Mosquitoes from La Victoria might also involve cytochrome P
. Therefore, organophosphates and carbamates are suggested to currently control
. Its use might reduce the frequency of resistance genes to pyrethroids and vector abundance and may impede the transmission of malaria parasites.