The Impact of Improved Lid of Underground Tanks “Tanka” On Breeding of An. Stephensi In Western Rajasthan, India

Background: Western Rajasthan of India has a typical desert climate. Until the introduction of canal water irrigation system, malaria was an unstable and seasonal occurrence. Due to scarcity of water, community practiced to have one large underground tank (locally known as Tanka) in their house to store water for long term use. Anopheles stephensi, one of the major malaria vectors, breeds in these "Tankas” if not properly covered and harbor a vector population throughout the year. Methods: Two villages Ajasar (intervention) and Tota (control) with similar ecological features were selected for the study. A pre-assessment was carried out in both villages to assess lids of Tankas, their breeding profile and the adult mosquito density. Awareness of community about malaria and mosquitoes was also assessed during pre-assessment period. In intervention village, lids were replaced with improved polyvinyl lids that were mosquito proof and last longer than conventional lids. Fitness of the lids, was assessed after one year. Entomological assessment was carried out in both intervention and non-intervention villages. The level of awareness of community was assessed both during pre and post intervention.Results : During the pre-assessment, Anopheles breeding was found in 22.1% (58/262) of Tankas of intervention village and 27.1% (19/70) of Tankas of control village. Tankas with iron lids were mainly positive in the intervention village (48.3%) and the control village (42.1%). In intervention village, 200 lids were replaced, and zero positivity was achieved. Before intervention, the species composition of An. stephensi was 46% in intervention and 55% in control village. Per Man Hour Density (PMHD) of An. stephensi was significantly reduced to 0.55 (94.95%) and 0.22 (97.8%) in post-intervention and follow-up, respectively in intervention village. Discussion: The adult density of An. stephensi was reduced significantly (97.8%) in intervention village. Breeding in underground tankas was completely checked in intervention village as compared to the control, where no such substantial reduction was observed. The awareness level of the community was also improved due to their involvement in the study.Conclusion: The study demonstrated that the small changes and interventions to reduce mosquitogenic conditions can be cost effective and long-lasting which may be helpful in control of malaria.

Efficacy of extended release formulations of Natular™ (spinosad) against larvae and adults of Anopheles mosquitoes in western Kenya

Background Larval source management is recommended as a supplementary vector control measure for the prevention of malaria. Among the concerns related to larviciding is the feasibility of implementation in tropical areas with large numbers of habitats and the need for frequent application. Formulated products of spinosad that are designed to be effective for several weeks may mitigate some of these concerns. Methods In a semi-field study, three formulations of spinosad (emulsifiable concentrate, extended release granules and tablet formulations) were tested in naturalistic habitats in comparison to an untreated control. Cohorts of third instar Anopheles gambiae (Diptera: Culicidae) were introduced into the habitats in screened cages every week up to four weeks after application and monitored for survivorship over three days. A small-scale field trial was then conducted in two villages. Two of the spinosad formulations were applied in one village over the course of 18 months. Immature mosquito populations were monitored with standard dippers in sentinel sites and adult populations were monitored by pyrethrum spray catches. Results In the semi-field study, the efficacy of the emulsifiable concentrate of spinosad waned 1 week after treatment. Mortality in habitats treated with the extended release granular formulation of spinosad was initially high but declined gradually over 4 weeks while mortality in habitats treated with the dispersable tablet formulation was low immediately after treatment but rose to 100% through four weeks. In the field study, immature and adult Anopheles mosquito populations were significantly lower in the intervention village compared to the control village during the larviciding period. Numbers of collected mosquitoes were lower in the intervention village compared to the control village during the post-intervention period but the difference was not statistically significant. Conclusions The extended release granular formulation and the dispersible tablet formulations of spinosad are effective against larval Anopheles mosquitoes for up to four weeks and may be an effective tool as part of larval source management programmes for reducing adult mosquito density and malaria transmission.

A Community-based Lifestyle Education Program Addressing Non-communicable Diseases in Low-literacy Areas of the South Pacific: A Pilot Control Cohort Study

Lifestyle interventions can effectively reduce chronic disease risk factors. This study examined the effectiveness of an established lifestyle intervention contextualized for low-literacy communities in Fiji. Ninety-six adults from four villages, with waist circumference (WC) indicative of risk of chronic disease, were randomly selected to an intervention or control group. Process evaluation indicated one intervention and one control village fulfilled the study protocol. There were no differences between intervention and control for body mass index BMI (P = 0.696), WC (P = 0.662), total cholesterol (TC) (P = 0.386), and TC:high-density lipoprotein (HDL) ratio (P = 0.485). The intervention village achieved greater reductions than the control village at 30 and 90 days for systolic blood pressure (30 days: −11.1% vs. −2.5%, P = 0.006; 90 days: −14.5% vs. −6.7%, P = 0.019); pulse rate (30 days: −7.0% vs. −1.1%, P = 0.866; 90 days: −7.1% vs. 4.3%, P = 0.027), and HDL (30 days: −13.9% vs. 1.7%, P = 0.206; 90 days: −18.9% vs. 2.2%, P = 0.001); at 90 days only for diastolic blood pressure (−14.4% vs. −0.2%, P = 0.010); at 30 days only for low-density lipoprotein (−11.6% vs. 8.0%, P = 0.009); and fasting plasma glucose (−10.2% vs. 4.3%, P = 0.032). However, for triglycerides, the control achieved greater reductions than the intervention village at 30 days (35.4% vs. −12.3%, P = 0.008; marginal at 90 days 16.4% vs. −23.5%, P = 0.054). This study provides preliminary evidence of the feasibility and potential effectiveness of the intervention to lower several risk factors for chronic disease over 30 days in rural settings in Fiji and supports consideration of larger studies.

Impact of the “BALatrine” Intervention on Soil-Transmitted Helminth Infections in Central Java, Indonesia: A Pilot Study

Many latrine campaigns in developing countries fail to be sustained because the introduced latrine is not appropriate to local socio-economic, cultural and environmental conditions, and there is an inadequate community health education component. We tested a low-cost, locally designed and constructed all-weather latrine (the “BALatrine”), together with community education promoting appropriate hygiene-related behaviour, to determine whether this integrated intervention effectively controlled soil-transmitted helminth (STH) infections. We undertook a pilot intervention study in two villages in Central Java, Indonesia. The villages were randomly allocated to either control or intervention with the intervention village receiving the BALatrine program and the control village receiving no program. STH-infection status was measured using the faecal flotation diagnostic method, before and eight months after the intervention. Over 8 months, the cumulative incidence of STH infection was significantly lower in the intervention village than in the control village: 13.4% vs. 27.5% (67/244 vs. 38/283, p < 0.001). The intervention was particularly effective among children: cumulative incidence 3.8% (2/53) for the intervention vs. 24.1% (13/54) for the control village (p < 0.001). The integrated BALatrine intervention was associated with a reduced incidence of STH infection. Following on from this pilot study, a large cluster-randomised controlled trial was commenced (ACTRN12613000523707).

Worm-free children: an integrated approach to reduction of soil-transmitted helminth infections in Central Java

Among children, infections with soil-transmitted helminths (STH) can cause anemia, impaired growth, and absence from school. Sustainable control of STH infection requires that appropriate latrines be integrated with health-promotion education. We report a pilot study of the effects of a combined latrine-education intervention in Central Java, Indonesia. The participants were 99 children (3–13 years old) in two villages (intervention and control) south of Semarang city. Stool samples were collected from the children and were examined for the presence of helminth eggs. After baseline data were collected, latrines were constructed and health education was given in the intervention village. Then, in both villages, all children who had STH infection at baseline were given 400 mg of albendazole. Eight months later, follow-up stool samples were collected and examined. In both villages, 20% of the children had STH infection at baseline. At follow-up, the incidence of STH infection was much lower in the intervention village than in the control village (4.0% vs. 20.4%; p<0.02). The results of this small pilot study give some confidence that a scaled-up study involving many more children and cluster-randomization of the intervention will be feasible and could provide more conclusive evidence of the intervention’s effectiveness.