Practical Control Methods and New Techniques for Mosquito Control

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sistance and improve the control efficacy (Furnival-Adam et al. 2020). There are several

products available on the market for private/residential purchase and professional mosquito

control use. Any application should follow the product labels and instructions to select the

ITN and LLIN for specific control program needs. Najera & Zaim (2002) provided detail

instructions and guidelines about decision-making criteria and procedures for judicious

use of insecticides for malaria vector mosquito control. These guidelines benefit all vector

mosquito control. The WHO’s Pesticide Evaluation Scheme recommended the following

insecticide products for the treatment of mosquito nets: Alpha-cypermethrin 10% suspen-

sion concentrate (SC) (active ingredient (a.i.) in 20-40 mg/m² of netting) at 6 mL per net,

Cyfluthrin 5% oil in water emulsion (EW) (a.i. in 50 mg/m² of netting) at 15 mL per net,

Deltamethrin 1% SC (a.i. in 15-25 mg/m² of netting) at 40 mL per net and 25% WT 25%

(water dispersible table at 1 table), Etofenprox 10% EW (a.i. in 200 mg/m² of netting) at 30

mL per net, Lambda-cyhalothrin 2.5% capsule suspension (CS) (capsule suspension) (a.i.

in 10-15 mg/m² of netting) at 10 mL per net, and Permethrin 10% emulsifiable oncentrate

(EC) (a.i. in 200-500 mg/m² of netting) at 75 ml per net.

1.6

NEW CONTROL TECHNIQUES

1.6.1

Genetic Control, Gene Drive, and GMO

Genetic control of mosquitos is a form of biological control of mosquitos, which ex-

ploits the mosquitos-mate-seeking expertise to introduce genetic abnormalities into the

eggs of the wild population of mosquitos (WHO 2019). Genetics provide new, species-

specific, and environmentally friendly methods /tools for control of mosquitos. Genetic

control aims either to suppress target populations or to introduce a harm-reducing novel

trait and intends to persist indefinitely in the target mosquito population, and may in-

vade other populations (Alphey 2013). A next-generation control tools for mosquito-borne

diseases has been designed to eliminate mosquito populations or to replace them with

mosquitos that are less capable of transmitting major pathogens due to recent advances in

CRISPR/Cas9-based genome editing, such as pathogen-resistant lines, new genetics-based

sexing strain (Bernardini et al. 2018) and methods, driving desirable genetic traits into

mosquito populations (Caragata et al. 2020).

Capitalizing on the RNA interference (RNAi) machinery to suppress interest genes of

mosquitos may be a promising direction for mosquito control. The RNAi pathway could be

activated via RNA molecule with a double-stranded appearance (RNAi triggers), resulting

in silencing of target genes. This approach could provide a new paradigm for mosquito con-

trol in the future (Airs & Bartholomay 2018). There are many studies about transgenes and

fitness and strain replacement in the laboratory and field trails. Oxitech, a U.K. company,

has developed several genetically modified strains of Aedes aegypti. Field studies have

shown success of strain OX513A, which has been tested in the Cayman Islands, Panama,

Malaysia, and Brazil. The OX513A mosquito strain has been produced to alter the female

offspring to die in the larval stage, thus preventing adult mosquitos from emerging. Release

of a new strain, OX5034, has been developed and was tested in south Florida in 2021.