Repository logo
 

Investigating the resistance status to permethrin and temephos in Aedes aegypti (the yellow fever mosquito)

Simple item page
dc.contributor.authorArthur, Nicholas Wynne, author
dc.contributor.authorNorton, Andrew, advisor
dc.contributor.authorCamper, Matt, committee member
dc.contributor.authorKading, Rebekah, committee member
dc.contributor.authorSaavedra-Rodriguez, Karla, committee member
dc.date.accessioned2024-05-27T10:32:03Z
dc.date.available2024-05-27T10:32:03Z
dc.date.issued2024
dc.description.abstractAedes aegypti (Ae. aegypti) is the principle urban vector of several viruses of high medical significance which carry a disease burden on a global scale. Ae. aegypti is anthropophilic and lives in close association with humans. This places nearly half of the global population at risk of becoming infected with an arboviral pathogen every year. Therefore, emphasis must be placed on investigating methods for controlling this vector to combat and reduce the spread of human disease. This is especially true in areas where socioeconomic factors promote sustained transmission cycles. While vector control programs use a variety of strategies, the primary method of reducing vector populations is through insecticide use. Widespread use of insecticides has placed intense selection pressures on Ae. aegypti populations and resistance mechanisms have developed. Target site modifications and the expression of detoxifying enzymes are the most significant resistance mechanisms to date. Several single nucleotide polymorphisms resulting in amino acid changes within the voltage-gated sodium channel (VGSC) have been shown to reduce binding site sensitivity and confer resistance to pyrethroids. Specifically, mutations at the knockdown-resistant (kdr) 410, 1,016, and 1,534 sites have been associated with a reduction in pyrethroid sensitivity. I investigated the resistance status to permethrin and temephos at five locations in Hidalgo County, Texas. I determined the presence of permethrin resistance using a well-characterized susceptible colony as a reference for insecticide sensitivity. The resistant allele C1,534 reached fixation at all sites and L410 and I1,016 were found at high frequencies. The permethrin resistance was over 40-fold when compared to the reference colony. The sites were less resistant to temephos at approximately 6-fold to 12-fold, which I attributed to cessation of this insecticide in the continental United States since 2016. In the absence of selection pressures mosquito populations trend towards susceptibility, which suggests that there are potential fitness costs associated with insecticide resistance. Studying these associations is important to public health as they may support different strategies to reduce vector populations. I used two collections from Tapachula, Mexico, that were free of pyrethroid exposure since 2013, to determine the presence of two previously described fitness cost metrics: wing length and egg production. I found that the average wing length of V410L and V1,016I homozygous resistant individuals were significantly smaller compared to homozygous susceptible individuals. The interaction between wing length and genotype had no effect on egg production. Wing length had no significant effect on egg production. Most notably, L410 and I1,016 resistant alleles had no effect on egg production.
dc.format.mediumborn digital
dc.format.mediummasters theses
dc.identifierArthur_colostate_0053N_18304.pdf
dc.identifier.urihttps://hdl.handle.net/10217/238422
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado State University. Libraries
dc.relation.ispartof2020-
dc.rightsCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.
dc.titleInvestigating the resistance status to permethrin and temephos in Aedes aegypti (the yellow fever mosquito)
dc.typeText
dcterms.rights.dplaThis Item is protected by copyright and/or related rights (https://rightsstatements.org/vocab/InC/1.0/). You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
thesis.degree.disciplineAgricultural Biology
thesis.degree.grantorColorado State University
thesis.degree.levelMasters
thesis.degree.nameMaster of Science (M.S.)

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Arthur_colostate_0053N_18304.pdf
Size:
2.14 MB
Format:
Adobe Portable Document Format
Download

Collections

2020-
Theses and Dissertations