Effect of household water treatment with chlorine on diarrhea among children under the age of five years in rural areas of Dire Dawa,eastern Ethiopia:a cluster randomized controlled trial

Background:Diarrheal disease is a leading cause of child mortality and morbidity worldwide.Household water treatment with chlorine significantly reduces morbidity due to waterborne diseases.However,the effect of point-ofuse(POU)water treatment in improving the quality of water in areas where POU is not provided free of charge and the effectiveness of home visits in inspiring household members to use POU regularly have not been studied.The objective of this study was to evaluate the effectiveness of drinking water disinfection by chlorination on diarrheal disease reduction among children under the age of 5 years in rural eastern Ethiopia.Methods:A cluster randomized controlled trial was carried out in rural Dire Dawa from October 2018 through January 2019.The 405 households were randomized to intervention and control arms and intervention materials were distributed after conducting a baseline survey.This trial evaluated the effectiveness of household drinking water disinfection by chlorination in reducing incidence of diarrhea among children under the age of 5 years.Intervention households received 1.2%sodium hypochlorite with demonstration of its proper use.Participants in the control households continued with their usual habits of water collection and water storage.Generalized estimation equations(GEE)with log link Poisson distribution family and exchangeable correlation matrix was used to compute crude incidence rate ratio(IRR),adjusted IRR and the corresponding 95%confidence intervals.Results:In the intervention households,in total,281 cases of diarrhea were documented(8.7 cases per 100 personweeks observation);in the control households,in total 446 cases of diarrhea were documented(13.8 cases per 100 person-weeks observation).A 36.0%(adjusted IRR=0.64,95%CI:0.57–0.73)reduction in incidence of diarrhea was observed in the intervention arm when compared with the control arm.The highest and the lowest reductions were obtained in children of age ranges 1 to 2 years and 3 to 4 years,42.7 and 30.4%,respectively.Adherence to the intervention was 81.3%as measured by free residual chlorine test.Conclusions:In rural areas where diarrhea is the second leading cause of morbidity,water chlorination at the household level using liquid bleach considerably reduced episodes of diarrhea among children under the age of 5 years.Therefore,chlorinating drinking water at the household level may be a valuable interim solution for reducing the incidence of diarrheal diseases until potable water is made accessible to the majority of the population in Dire Dawa Administration and other Ethiopian communities.

Gravid oviposition sticky trap and dengue non-structural 1 antigen test for early surveillance of dengue in multi-storey dwellings: study protocol of a cluster randomized controlled trial

Background:Dengue is a global disease,transmitted by the Aedes vectors.In 2018,there were 80615 dengue cases with 147 deaths in Malaysia.Currently,the nationwide surveillance programs are dependent on Aedes larval surveys and notifications of lab-confirmed human infections.The existing,reactive programs appear to lack sensitivity and proactivity.More efficient dengue vector surveillance/control methods are needed.Methods:A parallel,cluster,randomized controlled,interventional trial is being conducted for 18 months in Damansara Damai,Selangor,Malaysia,to determine the efficacy of using gravid oviposition sticky(GOS)trap and dengue non-structural 1(NS1)antigen test for early surveillance of dengue among Aedes mosquitoes to reduce dengue outbreaks.Eight residential apartments were randomly assigned into intervention and control arms.GOS traps are set at the apartments to collect Aedes weekly,following which dengue NS1 antigen is deteaed in these mosquitoes.When a dengue-positive mosquito is detected,the community will be advised to execute vector search-and-destroy and protective measures.The primary outcome concerns the the percentage change in the(i)number of dengue cases and(ii)durations of dengue outbreaks.Whereas other outcome measures include the change in density threshold of Aedes and changes in dengue-related knowledge,attitude and practice among cluster inhabitants.Discussion:This is a proactive and early dengue surveillance in the mosquito vector that does not rely on notification of dengue cases.Surveillance using the GOS traps should be able to efficiently provide sufficient coverage for multistorey dwellings where population per unit area is likely to be higher.Furthermore,trapping dengue-infected mosquitoes using the GOS trap,helps to halt the dengue transmission carried by the mosquito.It is envisaged that the results of this randomized controlled trial will provide a new proactive,cheap and targeted surveillance tool for the prevention and control of dengue outbreaks.Trial registration:This is a parallel-cluster,randomized controlled,interventional trial,registered at ClinicalTrials.gov(ID:NCT03799237),on 8th January 2019(retrospectively registered).