Development Of Controlled Release Mosquito Repellent Patch
About the Practice
Our investigation particularly address following major areas: 1. Mosquitoes represent a key threat to millions of humans and animals worldwide, since they act as vectors for deadly parasites and pathogens, including malaria, yellow fever, filariasis, Japanese encephalitis, dengue, chikungunya, West Nile and Zika virus. These mosquito-borne diseases incapacitate and seriously debilitate millions of people and unfortunately, decimate countless lives annually. In addition, mild or symptoms-free infections and the lack of effective medical treatments for some of these diseases further alleviate the sufferings and economic consequences among populations. Though vaccines for dengue, malaria and Japanes encephalitis are available, but their implications have been restricted due to various reasons. For instance, Dengvaxia, (Dengue vaccine) a tetravalent live attenuated vaccine developed by Sanofi Pasteur is presently available in some parts of the world, but its implications have been restricted due to various reasons including the higher rates of hospital admissions in vaccinated seronegative individuals (due to Dengvaxia raising non-protective dengue infection enhancing antibodies) and others. While the RTS,S/AS01 (RTS,S) vaccine is effective against Plasmodium falciparum, but unfortunately it does not offer protection against Plasmodium vivax malaria, which predominates in many countries outside of Africa. Moreover, these vaccines currently available are quite expensive, thus not readily available for poor and marginalized populations in tropical and subtropical areas worldwide. Thus, these problems warrant further development in the mosquito control strategies. 2. Currently, control of mosquito vectors use integrated approach employing many intervention methods simultaneously. These methods primarily include, synthetic insecticides, long lasting insecticidal nets, sterile insect technique, transgenic mosquitoes and synthetic repellents, which have produced encouraging results, however none of these strategies used singly has been proved to be fully successful. Moreover, the applicability of many commercially available synthetic anti-mosquito formulations has abridged noticeably, and this can be attributed to their toxic effects, both on the environment and also on different non-target organisms. Additionally, emerging problem of developing resistance in mosquitoes to these anti-mosquito formulations has been a serious concern. 3. Further, compromised stability is a serious problem associated with devices designed to deliver volatile repellent compounds. Therefore, stability testing is considered as a significant pre-requisite criterion that warrants the efficiency and safety of a particular pharmaceutical product to sustain its properties throughout its declared shelf life under predefined conditions. 4. Botanical essential oils (e.g., citronella oil, eucalyptus oil, and other plant oils) and their derivatives such as para-menthane-3,8-diol, a derivative of Eucalyptus citriodora, (currently used in Europe) also play a promising role in preventing disease transmission. However, the number of essential oil based commercial biopesticide remains low chiefly due to strict legislation, low persistence of effects, lack of proper quality control procedure and sufficient quantities of materials for affordable prices. Additionally, the presumed toxic effects such as allergenicity, genotoxicity, mutagenicity and negative effects on the human endocrine system have negated the commercial availability. 5. Therefore, in the light of these problems, a user-friendly personal mosquito repellent patch was fabricated by incorporating a promising and non-toxic repellent, ethyl anhranilate in a rate controlling polymeric matrix. Our patch exhibited the following characteristics: a) The patch was found effective against Ae. aegypti, An. stephensi and Cx. quinquefacsiatus mosquitoes for up to 4 h. b) The manufacturing cost is low as compared to commercial patch that would make it readily available to poor and marginalized populations. c) The patch remained stable for up to 6 months under accelerated stability conditions. d) No appreciable and observable toxicological impacts were noted following the application of the patch. Thus, it can be used successfully as an alternative to existing synthetic repellents without any potential health hazards. e) It avoids irritation and sensitization of the skin which occurs in at least a significant subset of the population of subjects when contacted with the active agent in liquid or solid form such as creams, emulsions, sprays, etc. f) In addition, being a non-invasive formulation, self administration is possible and if toxicity were to develop, the effect could be limited by removing the formulation. g) It may be affixed to hat, collar, cuffs, shirt, belt, pant, boots, socks, and certainly may also be affixed to furniture, walls, or appliances too. Apparently, due to these flexibilities in application, they can be carried anywhere and used whenever deemed necessary. Moreover, the patch can be used successfully to the places with convenient electricity supply. Thus, it will be suitable for travellers, indoor-outdoor workers, field workers and most importantly for military personnel.
Detail:
Mosquito-borne diseases such as malaria, dengue, Zika fever, yellow fever, filariasis, chikungunya, and Japanese encephalitis impose a remarkable clinical challenge that has considerable influence on morbidity and mortality of patients, resulting in huge impact on economy. Consequently, numerous anti-mosquito products have emerged currently on the market often claiming to significantly reduce biting pressure and/or increasing personal protection. However, environmental concerns, harmful health effects and costs of many anti-mosquito formulations have led to the present advancement of a safe non-toxic and inexpensive topical matrix type polymeric patch fabricated by incorporating ethyl anthranilate (EA), also known as ethyl 2-aminobenzoate, a non-toxic and FDA approved volatile food additive in a matrix of polymers and plasticizer for mosquito control. Initially, the efficacy of pure EA was investigated against three major mosquito vectors namely, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus under laboratory conditions as per the WHO guidelines. Thereafter, EA loaded mosquito repellent patches (EAMRPs) were developed and optimized by statistical software by employing a three factor, Box-Behnken design. The best optimized EAMRPs were then characterized by different analytical techniques. The EAMRPs were subjected to stability testing as per the International Conference on Harmonization (ICH) guideline for six months under accelerated conditions. The efficacy of EAMRPs was also investigated against mosquitoes both at laboratory and semi field settings. Finally, toxicological impacts of EAMRPs were explored as per the Organisation for Economic Co-operation and Development (OECD) guidelines on respiratory system following acute and sub-chronic inhalation exposure in Wistar rats. Cutaneous and acute oral toxicity assessment was also investigated. In preliminary investigation, the pure EA exert significant repellent activity against all three laboratory reared mosquito species. The best optimized EAMRPs were found to be thin, circular, opaque, homogenous, non-sticky, 100% flat, uniform and flexible in nature. The release of EA was found to follow the Higuchi kinetic model. In stability testing the best optimized EAMRPs remained stable for six months under accelerated conditions. Further, in efficacy assessment EAMRPs provided promising results against mosquitoes. In addition, no appreciable adversities were observed in toxicity studies. Thus, EAMRPs developed in the present research could successfully be used as an effective, eco-friendly, acceptable and safer alternative to the existing harmful repellents for personal protection against different hematophagous mosquito species without any potential health hazards.
About the Innovator
Address: Dr. Md. Johirul Islam Research Associate Molecular Immunology and Immunogenetics Laboratory Room no. 210 Department of Molecular Biology and Biotechnolgy Tezpur University Napam- 784 028, Assam, India
City: Napam
State: Assam
PIN Code 784 028
Email: islam_j@tezu.ernet.in
Contact No: 8011205349.999999
Practice Details
Link: To our best of knowledge ethyl anthranilate loaded mosquito repellent patch has been developed by us for the first time.
Problem Scale: Worldwide
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