Inuence of Indoor Residual Spay on An. Gambiae S.L. and An. Funestus Abundance, Resting Behavior and Community Perception on Irs Intervention In Kagera-Tanzania

: 21 Background : There has been a persistence of malaria transmission in Kagera Region despite 22 consecutive phases of indoor residual spraying (IRS) targeting malaria vectors. In addition to sprayed area. Community sensitization before, during and after IRS application needs to be strengthen for getting intended results.

Introduction children under five years of age was 32% in Geita region, which was the highest prevalence 71 compared to other regions in Tanzania [4].

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A number of factors interact to influence the transmission of malaria. These factors includes the 74 quality of insecticides, human behaviors and practices such as fishing, agriculture and staying 75 outside while getting dinner/sapper, effectiveness of IRS and LLINs, mosquito feeding behaviors 76 and weather conditions of a specific area interact altogether to influence the resting behaviors of 77 malaria vectors [5]. Anopheles species have different resting and feeding behaviors [6]. 78 Chemicals used as insecticides such as Dichloro Diphenyl Trichloroethane (DDT) are irritant to 79 malaria vectors; therefore force them to exit houses quickly after entering them. When 80 mosquitoes cannot obtain blood meals indoors, they will obtain it outdoors in which they may 81 either feed on people outside houses or on animals these mosquitoes will continue surviving and 82 will account for residual malaria transmission [7]. Insecticides used for IRS and LLINs have 83 been reported to influence the malaria vectors' abundance, resting behaviors and species 84 composition [8,9].

Data collection using questionnaires and interview guide
A total of 396 heads of households were randomly selected and interviewed using structured 166 questionnaires. Four focused group discussions (FGDs) were conducted two in each district.

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Each group was composed of eight members aged 18 years and above.   (Table 1).     Missenyi and Karagwe, respectively do not use any measure to protect themselves against 238 mosquito bites while to go out at night for a refreshments. In Missenyi, only 13.6% (n=27) wear 239 long sleeved shirts and trousers for protection and 1.5% (n=3) respondents reported using 240 mosquito repellants (Table 3).                    study were also dissimilar to a study conducted in western Kenya whereby IRS using pirimiphos-341 methyl was associated with 88% reduction in An. funestus numbers in intervention areas compared to non-intervention areas [32]. Indoor residual spray with pirimiphos-methyl has 343 reported to maintain sporozoite rates at low levels hence an important tool for malaria vector    The present study has revealed the behaviors that predispose community member to mosquito In the present study the community members in Missenyi and Karagwe districts agreed that, IRS 446 implementation is a useful control measure against malaria vectors. All participants reported that 447 malaria transmission have declined by comparing before and after IRS. As a participant from 448 Missenyi added that "You know in the past every minute you go to hospital they tell you that you 449 have malaria but nowadays it is not easy, or even if they say it is malaria, it is not severe as that 450 of the past before these chemicals". Our findings are similar to previous studies conducted in 451  The present study has revealed the perceived low efficacy of the insecticides used during IRS.

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The participants reported an increase of mosquitoes later after IRS campaign as pointed out by a 468 woman from Missenyi "To be sincere, in the first three months after spraying, the mosquitoes 469 are few but thereafter, the numbers of mosquitoes increase even more" and also a woman from 470 Karagwe who added that "Last year after spraying, mosquitoes did not die". These findings are  In the present study, few participants also mentioned some behavioral factors such as washing 476 walls, repainting, plastering and covering walls using newspapers after IRS which may hinder In the present study, most of the participants reported on a number of factors that might influence 503 the effectiveness and efficiency of IRS, which are either due to the community itself or from 504 spray operators. Participants reported cases of chemicals not being mixed in the required ratios, 505 not spraying some houses, selling of chemicals to farmers to be used in gardens for killing pests.