Overview of Personal Protection Measures Through the Innovative

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3.5

IMPREGNATION OF TEXTILE

Impregnation of fabrics with repellents is a method reported to reduce bites by in-

sects. This method works just like the impregnation of mosquito nets with Pyrethroid

derivatives like Permethrin making them Long-Lasting Insecticide-Treated Nets (LLITNs)

which is considered an efficacious vector control strategy especially for indoor feeding

vectors. A large percentage of the human skin is covered by the treated fabric thus reduc-

ing exposure to the disease vectors. Imparting the mosquito repellents onto the textile and

cloth-impregnating laundry emulsions application is one of the innovatory and practical

approaches in daily routine to driving away blood-sucking arthropods from people (Brown

and Hebert 1997; Maheshwari and Ramya 2014).

Permethrin, first marketed in 1973, a laboratory-manufactured pyrethroid insect repel-

lant and contact insecticide; derived from the crushed dried flowers of Chrysanthemum

cinerarifolium is a broad spectrum, non-systemic, synthetic pyrethroid insecticide that tar-

gets adults and larvae of many species of biting, chewing, scaling, soil, and flying inverte-

brates (Diaz 2016). Permethrin is approved by the United States Environmental Protection

Agency (EPA) as an insecticide for use on crops, animals, buildings and fabric. It is not

absorbed topically therefore it requires direct contact; the reason why it is referred to as a

contact repellent. It’s mechanism of action is through altering the nervous system by mod-

ifying the nerve membrane sodium channel. When applied to clothing, bed nets, tents, and

sleeping bags, permethrin and other synthetic Pyrethroids (Allethrin, Alpha-cypermethrin,

Cyfluthrin, Deltamethrin, Etofenprox, Lambda-cyhalothrin, and Metofluthrin) all provide

very high-level protection against mosquitos, flies, biting midges, chiggers, fleas, sandflies,

and ticks, especially when combined with topically applied insect repellents (Diaz 2016).

There are numerous ways to assess the efficacy of treated textiles for impregnated tex-

tiles. The methods are cone test, cage test, field test and excito chamber (Sritabutra et al.

2011; Standards 2006; Tawatsin et al. 2001; WHO 1996). Textiles impregnated with re-

pellents like LLINs drive the vector away from the treated surface, or depending on the

concentration may cause knock down or mortality. The interruption of host-seeking re-

quires proper understanding of host-seeking behaviors employed by disease vectors and

is very promising in the development of vector control strategies. The applications of the

mosquito repellent feature must not damage the original characteristic of the textile mate-

rials itself. Approaches aimed at curtailing wild vector populations inevitably rely on the

prevention of host-seeking or biting as an endpoint.

3.6

EVALUATION OF REPELLENTS

There are many disciplines involved in studying the use of a given repellent, the manu-

facturing process and in evaluating it’s performance; Chemistry, Engineering, Biology and

Entomology. Entomologists have to evaluate the necessary capacity to measure the effec-

tiveness of a repellent against mosquitos or arthropods, and to give indications to other

figures to improve the characteristics. The extracts of plants which are basically essen-

tial oil, have delicate physical and chemical properties, therefore during the engineering,