Research report

Bio-efficacy of Risasi Electric Mosquito Mat Against Anopheles Gambiae Anthropophilic Malaria Vectors  

Eliningaya Keka
1 Department of Medical Parasitology and Entomology, Catholic University of Health and Allied Sciences, P.O. Box 1464, Mwanza, Tanzania
2 Tropical Pesticides Research Institute, Division of Livestock and Human Diseases Vector Control, Mosquito Section, P.O. Box 3024, Arusha, Tanzania
Author    Correspondence author
Journal of Mosquito Research, 2016, Vol. 6, No. 32   doi: 10.5376/jmr.2016.06.0032
Received: 18 Sep., 2016    Accepted: 30 Oct., 2016    Published: 09 Dec., 2016
© 2016 BioPublisher Publishing Platform
This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract

The bioefficacy of mats prallethrin group of synthetic pyrethroid was studied against laboratory strains of Anopheles gambiae s.s..  This synthetic pyrethroid was evaluated against worn alone and work sock with DEET. Protection efficiency was highest 99.8% in Trap with Slow releasing mat, 92.5% in worn sock sprayed with DEET(20% active ingredient) and least (8.6%) in Trap with worn sock alone. The slow released mosquito electric mat has shown a very high protective efficacy than standard repellent DEET. A worn sock alone showed the normal mosquito attraction trend for all trapping hours which could be indicator of mosquito biting for unprotected group.  This study have shown Mats deterred 99.8% of the mosquitoes from been trapped on the CDC light trap for 10 hours. The use of these formulations as a control tools in reducing man-vector contact is important in controlling residual malaria transmission. In the light of these findings, a synthetic have shown to be efficient in indoor and enclosed outdoor environments against malaria and other biting mosquitoes in Tanzania.

Keywords
Repellents; Anopheles gambiae; Unworn sock; Worn Sock CDC-light trap

Introduction

Malaria vector control has been a major tool for malaria cases control through use of long lasting insecticidal nets (LLINs) and indoor residual spray (IRS) programs (Hamainza et al., 2016).  Although malaria decline is reported throughout endemic areas, residual malaria transmission stills a problem (Tusting et al., 2016; Walker et al., 2016). Residual malaria control needs more tools than, ITN and IRS alone. The use of mosquito repellent can be considered for the protection of residual malaria control (Sangoro et al., 2014; Mng'ong'o et al., 2011). In history, malaria vector – human contact has been used to control disease vector traditionally, either by burning whole plants (Kweka et al., 2008a) or by hanging the plants indoors (Seyoum et al., 2002; Hassanali et al., 2002; Seyoum et al., 2003). In advancement of science and technology, extraction and isolation of active repellent compounds of the plant material has been achieved and evaluated against disease vectors (Mukandiwa et al., 2016; Paluch et al., 2009; Chauhan et al., 2005).  Different plant based repellent have shown the protection efficiency of six to eight hours (Sanghong et al., 2015; Champakaew et al., 2015). The protection efficiency shown by these plants based repellents are similar to what observed with N,N-diethyl-meta-toluamide (DEET), a gold standard known repellent which have offered a protection of up to 8 hours since its inception in 1954 (Gupta et al., 1987).  The short comings of these topical repellents are skin irritations (Shutty et al., 2013) and inconsistent application of the person (Antwi et al., 2008). Due to existence of residual malaria transmission, the sensitive and reliable tools should be in place for better protection which does not need frequent reapplications. The uses of mosquito coils for repelling vectors have found to be efficient for 6 – 8 hours (Msangi et al., 2010). This is only efficient to protect during the first biting cycle of the principal malaria vectors (6-10pm) and expose the person to mosquito bites after 6-8 hours (Msangi et al., 2010).

 

At the moment different mats with different active ingredients such as allethrin and bioallethrin have been evaluated and proved to have protective efficacy against different species of disease caring biting mosquitoes (Dua et al., 2005; Amalraj et al., 1996; Amalraj et al., 1992). The efficacy was against strains of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Amalraj et al., 1996).

 

The essence of this trial was to evaluate Risasi, an electric mosquito mat repellent protection efficiency against free fly An. gambiae s.l.. The elective mosquito mat (EMM), the active ingredient is prallethrin, 18mg/mat which is 12% of net content (150mg/mat) of chemical ingredients. These EMM are proposed to be protective for 10 hours.

 

1 Materials and Methods

1.1 Material evaluated and procedure

Material evaluated was Risasi (Electric mosquito mat (EMM)) which is pyrethroid based repellent. Its active ingredient is prallethrin (18mg/mat) which is intended for 10 hours protections against biting mosquitoes. These mats were manufactured on 5th April, 2016 and expected to expire on 4th, April 2019 with a batch No. RMM01.

 

1.2 Experimental design

The use of human as a subject in evaluation of repellents is regarded an ethical (Kilama, 2010). The better method have to be designed for the evaluation of repellents using mosquitoes behaviors response different studies, a worn sock for 8 – 10 hours has been validated to attract An. gambiae s s.l. as good as a whole human body (Mukabana et al., 2012). A nylon socks were used for collecting whole human odour daily by been worn for 10 hours. This study had 3 arm assessing sampling efficiency of trap in different treatments and designs; (i) validation of worn sock alone against positive control (DEET) efficiency (ii) validation of worn sock alone against MEM  and, (iii) evaluation of the MEM, DEET and worn sock in the same time. The details of each experimental set up are described below.

 

1.3 Validation of worn sock alone against DEET (Positive control)

A pair of worn sock was obtained from a volunteer who worn them for 10 hours (8:00 to 18:00hrs). One sock was treated with DEET (composition of 20% DEET) spray (positive control) and other was left with worn sock alone (control). Each sock was placed in a CDC-light trap with minor modifications (the bulb was removed from the CDC-light trap to ensure that no light only a worn sock alone or a worn sock with repellent which monitored for effect of response for number of mosquitoes sampled per night. The room used for this evaluation had a size of 5 meters length by 5 meters width. Light traps were switched on after been loaded with worn sock and worn sock sprayed with DEET. The traps operated 30 minutes before the release of 200 unfed females of An. gambiae s.s., 3 days old. Trapped mosquito collection was done in hourly interval by 3 technicians. Each worked for four hours. Mosquito were kept in a paper cup well labeled for each hour and trap treatment. Treatment and control positions were rotated to avoid positional biasness. The experiment lasted for eight (8) days.

 

1.4 Validation of worn sock alone against mosquito electric mat (MEM)

The protocol was similar to section (i) above, except that the EMM was connected to power and switched on 30 minutes before mosquito release in the room. Traps with worn sock alone and the other with worn sock attached with EMM. Traps rotated positions to avoid positional effect on mosquito responses. The experiment lasted for eight (8) days.

 

1.5 Evaluation of three treatments at once

In the same room as described in (i) and (ii) above. The points were marked, (East, West, South) these traps with different treatments rotated in each point for 9 days (Latin square of 3x3) days. This rotation eliminated the positional effect. The rest of the procedures remained as (i) and (ii) above.

 

1.6 Data analysis

Data analysis was performed using GLM univariate analysis in which An. gambiae trapped were considered as dependant variable while days of experiments considered as random effect, treatment time was considered as fixed variable. Programme used for data Analysis was SPSS version 17 while significance level was considered below 5%.

 

2 Result

2.1 Comparison of trapping efficiency between a trap with worn sock alone with a trap with worn sock sprayed with DEET

The output of GLM univariate analysis showed that, trap location had no effect on sampling efficiency (F = 0.001, df = 2, P=1.000). Experimental days had no any random effect on sampling (F=1.278, df = 7, P=0.266). The treatments used in traps found that, the trap with work alone had higher number of mosquitoes trapped than in a trap with sock sprayed with DEET (df = 1 F= 424.36, P<0.001)(Figure 1).

 

 

Figure 1 The mean number of mosquitoes collected per night for each treatment

 

2.2 Risasi electric mosquito mat (EMM) against worn sock alone

The number of mosquitoes collected in a trap with worn sock alone was statistically higher than those in a trap attached to Risasi Electric mosquito mat slowly releasing prallethrin (F=256.25, df=1, P>0.001) (Figure 2). Position of the trap did not influence the differences on mosquito collection (F=0.434, P=0.511).

 

 

Figure 2 The mean number of mosquitoes collected per night for each treatment

 

The results of long term bioassay with Cx. vishnui group as prey and A.sardea as predator are presented in Table II. The rates of predation of A. sardea during the course of long-term experiments remained almost similar during the entire set of experiments as expressed in terms of clearance rates, which reflected the ability of the predators to regulate the mosquito larvae in real time situations.

 

2.3 Comparison of three traps at a time

Comparison of three treatments; a trap with a worn sock alone, another with DEET sprayed on worn sock and other with worn sock attached to Risasi electric mosquito mat slowly releasing prallethrin found have a significant variation in mosquito sampling with a trap attached with Risasi electric mosquito mat had least number of mosquito per right (F=353.78, df=2, P>0.001) (Figure 3). The position of any trap had no influence on the number of mosquitoes sampled per right (F=0.319, DF=2, P=0.727). The mean number of mosquitoes sampled hourly was lowest in mosquito electric mat than the rest (Figure 4).

 

 

Figure 3 The mean number of mosquitoes collected per night for three treatments

 

 

Figure 4 Hourly sampling of Anopheles gambiae s.s. from 7pm to 4am

 

3 Discussions

The findings of the trial have revealed that, the protection efficiency of the slow release Mosquito electric mat, with prallethrin (a synthetic pyrethroid) as active ingredient was 10 hours as indicated by manufacturer. These findings have exceeded the normal 6 hours shown by most topical repellants and coils used (Kweka et al., 2008b; Kweka et al., 2012). The standard topical repellant, DEET had shown to have protective efficacy of 8 hours (Kweka et al., 2008b), but could not reach 10 hours as slow release Mosquito electric mat.  These findings are similar to what was found by previous studies using slow release techniques with synthetic pyrethroid as an active ingredient (Amalraj et al., 1996; Amalraj et al., 1992).

 

The use of slow released repellent can be of great use against mosquitoes for the control of residual malaria transmission. The slow release containing prallethrin as active ingredient have inhibited anthropophilic malaria vectors for the longer than transfluthrin which was formerly used and another mosquito coils (Msangi et al., 2010). The slow release of prallethrin has shown a great achievement which can be useful in urban and rural areas where electricity is available. The slowly released prallethrin has shown a great efficiency to interrupt both early and late biting cycles of host seeking mosquitoes. This is an achievement which could control well a residual malaria transmission for those who will get out of the nest earlier in the morning and retire late in the evening. It is powerful tool to be used in indoor, enclosed outdoor environment such as night clubs, bars and pubs.

 

The wide coverage of LLINs and IRS program  have let to reduced biting rates indoor but enclosed areas outdoor experienced increased biting rates(Charlwood et al., 2016; Maia et al., 2016). The emerging of long lasting repellent with pyrethroid as active ingredient have led to a relief for outdoor population before retiring to their beds with LLINs.

 

4 Conclusion

The findings of this trial have shown extended protection efficiency if only used in enclosed areas where wind should not be blowing fast such as in open spaces. This efficacy has promising results to protect people and reduce or control residual malaria transmission.

 

Authors’ contribution

EJK designed the experiments and wrote the first draft of the manuscript and data analysis. Edited and reviewed the MS and agreed upon submission.

 

Acknowledgements

Authors wish to thank Adrian Massawe, Jamima Hamisy and Ibrahim Sungi for experiment set up and data recording. TPRI for provision of infrastructure to conduct the study. There was no financial assistance for this study.

 

References

Amalraj D., Sivagnaname N., Boopathidoss P., and Das P., 1996, Bioefficacy of mosquito mat, coil and dispenser formulations containing allethrin group of synthetic pyrethroids against mosquito vectors, The Journal of communicable diseases, 28: 85-93

PMid:8810142

 

Amalraj D.D., Kalyanasundaram M., and Das P.K., 1992, Evaluation of EMD vaporizers and bioallethrin vaporizing mats against mosquito vectors, Southeast Asian J Trop Med Public Health, 23: 474-478

PMid:1488702

 

Antwi F.B., Shama L.M., and Peterson R.K.D., 2008, Risk assessments for the insect repellents DEET and picaridin, Regulatory Toxicology and Pharmacology, 51: 31-36

https://doi.org/10.1016/j.yrtph.2008.03.002

PMid:18406029

 

Champakaew D., Junkum A., Chaithong U., Jitpakdi A., Riyong D., Sanghong R., Intirach J., Muangmoon R., Chansang A., Tuetun B., and Pitasawat B., 2015, Angelica sinensis (Umbelliferae) with proven repellent properties against Aedes aegypti, the primary dengue fever vector in Thailand, Parasitology Research, 114: 2187-2198

https://doi.org/10.1007/s00436-015-4409-z

PMid:25773182

 

Charlwood J.D., Nenhep S., Protopopoff N., Sovannaroth S., Morgan J.C., and Hemingway J., 2016, Effects of the spatial repellent metofluthrin on landing rates of outdoor biting anophelines in Cambodia, Southeast Asia, Medical and Veterinary Entomology, 30: 229-234

https://doi.org/10.1111/mve.12168

PMid:26991881

 

Chauhan K.R., Klun J.A., Debboun M., and Kramer M., 2005, Feeding Deterrent Effects of Catnip Oil Components Compared with Two Synthetic Amides Against Aedes aegypti, Journal of Medical Entomology, 42: 643-646

https://doi.org/10.1093/jmedent/42.4.643

https://doi.org/10.1603/0022-2585(2005)042[0643:FDEOCO]2.0.CO;2

 

Dua K.V., Gurwara R., Sinha N.S., and Dash P.A., 2005, Allethrin in the Air During the Use of a Heated Mosquito Repellent Mat, Bulletin of Environmental Contamination and Toxicology, 75: 747-751

https://doi.org/10.1007/s00128-005-0814-9

PMid:16400556

 

Gupta R.K., Sweeney A.W., Rutledge L.C., Cooper R.D., Frances S.P., and Westrom D.R., 1987, Effectiveness of controlled-release personal-use arthropod repellents and permethrin-impregnated clothing in the field, Journal of the American Mosquito Control Association, 3: 556-560

PMid:2904965

 

Hamainza B., Sikaala C.H., Moonga H.B., Chanda J., Chinula D., Mwenda M., Kamuliwo M., Bennett A., Seyoum A., and Killeen G.F., 2016, Incremental impact upon malaria transmission of supplementing pyrethroid-impregnated long-lasting insecticidal nets with indoor residual spraying using pyrethroids or the organophosphate, pirimiphos methyl, Malaria Journal, 15: 1-20

https://doi.org/10.1186/s12936-016-1143-7

PMid:26893012 PMCid:PMC4758014

 

Hassanali A., Seyoum A., Kung'a S., Kabiru E.W., Lwande W., Killeen G., and Knols B., 2002, Traditional use of mosquito-repellent plants in western Kenya and their evaluation in semi-field experimental huts against Anopheles gambiae: ethnobotanical studies and application by thermal expulsion and direct burning, Kilama W.L., 2010, Health research ethics in malaria vector trials in Africa, Malaria Journal, 9: 1-9

 

Kweka E.J., Mosha F., Lowassa A., Mahande A.M., Kitau J., Matowo J., Mahande M.J., Massenga C.P., Tenu F., Feston E., Lyatuu E.E., Mboya M.A., Mndeme R., Chuwa G., and Temu E.A., 2008a, Ethnobotanical study of some of mosquito repellent plants in north-eastern Tanzania, Malaria Journal, 7: 1-9

https://doi.org/10.1186/1475-2875-7-152

PMid:18687119 PMCid:PMC2519077

 

Kweka E.J., Mosha F.W., Lowassa A., Mahande A.M., Mahande M.J., Massenga C.P., Tenu F., Lyatuu E.E., Mboya M.A., and Temu E.A., 2008b, Longitudinal evaluation of Ocimum and other plants effects on the feeding behavioral response of mosquitoes (Diptera: Culicidae) in the field in Tanzania, Parasites & Vectors, 1: 1-8

https://doi.org/10.1186/1756-3305-1-42

PMid:18945343 PMCid:PMC2577633

 

Kweka E.J., Munga S., Mahande A.M., Msangi S., Mazigo H.D., Adrias A.Q., and Matias J.R., 2012, Protective efficacy of menthol propylene glycol carbonate compared to N, N-diethyl-methylbenzamide against mosquito bites in Northern Tanzania, Parasites & Vectors, 5: 1-10

https://doi.org/10.1186/1756-3305-5-189

PMid:22950604 PMCid:PMC3444865

 

Maia M.F., Kreppel K., Mbeyela E., Roman D., Mayagaya V., Lobo N.F., Ross A., and Moore S.J., 2016, A crossover study to evaluate the diversion of malaria vectors in a community with incomplete coverage of spatial repellents in the Kilombero Valley, Tanzania, Parasites & Vectors, 9: 1-13

https://doi.org/10.1186/s13071-016-1738-4

PMid:27527601 PMCid:PMC4986272

 

Mng'ong'o F.C., Sambali J.J., Sabas E., Rubanga J., Magoma J., Ntamatungiro A.J., Turner E.L., Nyogea D., Ensink J.H.J., and Moore S.J., 2011, Repellent Plants Provide Affordable Natural Screening to Prevent Mosquito House Entry in Tropical Rural Settings—Results from a Pilot Efficacy Study, PLoS ONE, 6: e25927

https://doi.org/10.1371/journal.pone.0025927

PMid:22022471 PMCid:PMC3192125

 

Msangi S., Mwang'onde B.J., Mahande A.M., and Kweka E.J., 2010, Field evaluation of the bio-efficacy of three pyrethroid based coils against wild populations of anthropophilic mosquitoes in northern Tanzania, Journal of global infectious diseases, 2: 116

https://doi.org/10.4103/0974-777X.62885

PMid:20606965 PMCid:PMC2889649

 

Mukabana W.R., Mweresa C.K., Omusula P., Orindi B.O., Smallegange R.C., Van Loon J.J., and Takken W., 2012, Evaluation of low density polyethylene and nylon for delivery of synthetic mosquito attractants, Parasites & Vectors, 5: 1-8

https://doi.org/10.1186/1756-3305-5-202

PMid:22992518 PMCid:PMC3480916

 

Mukandiwa L., Eloff J.N., and Naidoo V., 2016, Repellent and mosquitocidal effects of leaf extracts of Clausena anisata against the Aedes aegypti mosquito (Diptera: Culicidae), Environmental Science and Pollution Research, 23: 11257-11266

https://doi.org/10.1007/s11356-016-6318-9

PMid:26924698

 

Paluch G., Grodnitzky J., Bartholomay L., and Coats J., 2009, Quantitative Structure−Activity Relationship of Botanical Sesquiterpenes: Spatial and Contact Repellency to the Yellow Fever Mosquito, Aedes aegypti, Journal of Agricultural and Food Chemistry, 57: 7618-7625

https://doi.org/10.1021/jf900964e

PMid:19645502

 

Sanghong R., Junkum A., Chaithong U., Jitpakdi A., Riyong D., Tuetun B., Champakaew D., Intirach J., Muangmoon R., Chansang A., and Pitasawat B., 2015, Remarkable repellency of Ligusticum sinense (Umbelliferae), a herbal alternative against laboratory populations of Anopheles minimus and Aedes aegypti (Diptera: Culicidae), Malaria Journal, 14: 1-9

https://doi.org/10.1186/s12936-015-0816-y

PMid:26249666 PMCid:PMC4527275

 

Sangoro O., Kelly A.H., Mtali S., and Moore S.J., 2014, Feasibility of repellent use in a context of increasing outdoor transmission: a qualitative study in rural Tanzania, Malaria Journal, 13: 1-16

https://doi.org/10.1186/1475-2875-13-347

PMid:25182272 PMCid:PMC4283126

 

Seyoum A., Killeen G.F., Kabiru E.W., Knols B.G., and Hassanali A., 2003, Field efficacy of thermally expelled or live potted repellent plants against African malaria vectors in western Kenya, Tropical Medicine & International Health, 8: 1005-1011

https://doi.org/10.1046/j.1360-2276.2003.01125.x

PMid:14629767

 

Seyoum A., Pålsson K., Kung'a S., Kabiru E., Lwande W., Killeen G., Hassanali A., and Knots B., 2002, Traditional use of mosquito-repellent plants in western Kenya and their evaluation in semi-field experimental huts against Anopheles gambiae: ethnobotanical studies and application by thermal expulsion and direct burning, Transactions of the Royal Society of Tropical Medicine and Hygiene, 96: 225-231

https://doi.org/10.1016/S0035-9203(02)90084-2

 

Shutty B., Swender D., Chernin L., Tcheurekdjian H., and Hostoffer R., 2013, Insect repellents and contact urticaria: differential response to DEET and picaridin, Cutis, 91: 280-282

PMid:23837149

 

Tusting L.S., Willey B., and Lines J., 2016, Building malaria out: improving health in the home, Malaria Journal, 15: 1-3

https://doi.org/10.1186/s12936-016-1349-8

PMid:27306079 PMCid:PMC4910219

 

Walker P.G.T., Griffin J.T., Ferguson N.M., and Ghani A.C., 2016, Estimating the most efficient allocation of interventions to achieve reductions in Plasmodium falciparum malaria burden and transmission in Africa: a modelling study, The Lancet Global Health, 4: e474-e484

https://doi.org/10.1016/S2214-109X(16)30073-0

Journal of Mosquito Research
• Volume 6
View Options
. PDF(0KB)
. FPDF
. HTML
. Online fPDF
Associated material
. Readers' comments
Other articles by authors
pornliz suckporn sex videos bbw mom xxx big fucking arabin porn videos teen gril sex video riding hard cock woman hard vagina . Eliningaya Keka
Related articles
. Repellents
. Anopheles gambiae
. Unworn sock
. Worn Sock CDC-light trap
Tools
. Email to a friend
. Post a comment