Insecticide Resistance in Anopheles Albitarsis S.S. From a Rice Production Field, With the First Record of Kdr Mutation in This Species 

Abstract

Background: Although there is a vast literature concerning insecticide resistance (IR) in Plasmodium vectors from African and Asian continents, similar studies with Neotropical anophelines are scares. Herein we evaluated the IR profile of Anopheles albitarsis s.s. of a laboratory colony and a natural population collected around a rice plantation field. The laboratory colony is original from a collection performed in this same region more than two decades ago. Methods: We collected An. albitarsis females while resting after blood feeding, around rice field plantations in Massaranduba, SC, Brazil. These females laid their eggs in the laboratory, and the larvae were raised in parallel with our lab colony. To be sure about the field samples’ taxonomic status, we amplified and sequenced the mitochondrial COI gene of a sampling of field captured mosquitoes. We performed a simplified knockdown test with larvae exposed to permethrin and deltamethrin and submitted adult females to a WHO like tube test with the pyrethroids permethrin, deltamethrin, and etofenprox, in addition to the organophosphate malathion. A segment of the voltage-gated sodium channel gene (NaV) was amplified and cloned. Based on the observed sequences, we developed a TaqMan genotyping assay for the variation L1014F and calculated the genotypic and allelic frequencies concerning this SNP in the field population.Results: The COI analyses confirmed the taxonomic status of An. albitarsis s.s in laboratory and field samples. The field population was resistant to pyrethroids but not to malathion. We observed the substitutions L1019R, F1020S, and the classical kdr L1014F in the NaV gene. This classical kdr allele was present under low frequencies in the overall field population (2%), although more frequent in pyrethroid-resistant insects.Conclusions: The An. albitarsis s.s. population from Massaranduba was resistant to pyrethroids, likely due to selection pressure exerted by agrochemical pesticides. We registered the classical kdr mutation in a Brazilian Anopheles species for the first time. Further investigations are necessary to disclose additional resistance mechanisms.

Molecular diversity of genes related to biological rhythms (period and timeless) and insecticide resistance (Na V and ace-1) in Anopheles darlingi

“…albimanus in Central and North America, 18 , 94 selected due to the intense pressure exerted by vector control interventions with pyrethroids in IRS and LLITN 24 or in proximity to agricultural areas. 25 We did not find any non-synonymous variation in the Na V gene fragment of An. darlingi .…”

“…(9) The classic L1014F kdr mutation is reported in at least 14 Anopheles species, including the Neotropical An. albitarsis s.s. in southern Brazil (25) and on An. albimanus in Central and North America, (18,94) selected due to the intense pressure exerted by vector control interventions with pyrethroids in IRS and LLITN (24) or in proximity to agricultural areas.…”

“…albimanus and An. albitarsis s.s. 18 , 25 Organophosphates (OPs) and carbamates target the acetylcholinesterase enzyme, whereas mutations in the ace-1 coding gene are associated with resistance to OPs insecticide class. The substitution G119S in the ace-1 gene was found in resistant Culex pipiens 26 , 27 and species of the Anopheles gambiae complex cryptic species.…”

Mutations Linked to Insecticide Resistance Not Detected in the Ace-1 or VGSC Genes in Nyssorhynchus darlingi from Multiple Localities in Amazonian Brazil and Peru

“…However, the recent genotypic reporting of several Brazilian samples of Ny. albitarsis s.s. showed heterozygous L995F mutations in VGSC [52], and a sample of Guatemalan Ny. albimanus had a heterozygous G280S mutation in Ace-1 [69].…”

“…darlingi from Chocó Department, Colombia, that had been demonstrated to be phenotypically susceptible and resistant, sequenced for the same region of the VGSC gene, also did not reveal any kdr mutations [16]. However, the classic L1014F kdr mutation has been detected in other important anopheline malaria vectors, i.e., Nyssorhynchus albimanus [16,50,51] and Nyssorhynchus albitarsis s.s. [52]. Other species of Latin American malaria vectors evaluated with these molecular assays include Anopheles vestitipennis and Anopheles pseudopunctipennis, both of which exhibited genotypic susceptibility [16].…”