World Health Organization, 2013. Diarrhoeal Disease Available at: http://www.who.int/mediacentre/factsheets/fs330/en/. Accessed May 4, 2016.
Ali M, Nelson AR, Lopez AL, Sack DA, 2015. Updated global burden of cholera in endemic countries. PLoS Negl Trop Dis 9: e0003832.
Harris AM, Chowdhury F, Begum YA, Khan AI, Faruque AS, Svennerholm AM, Harris JB, Ryan ET, Cravioto A, Calderwood SB, Qadri F, 2008. Shifting prevalence of major diarrheal pathogens in patients seeking hospital care during floods in 1998, 2004, and 2007 in Dhaka, Bangladesh. Am J Trop Med Hyg 79: 708–714.
Schwartz BS, Harris JB, Khan AI, Larocque RC, Sack DA, Malek MA, Faruque AS, Qadri F, Calderwood SB, Luby SP, Ryan ET, 2006. Diarrheal epidemics in Dhaka, Bangladesh, during three consecutive floods: 1988, 1998, and 2004. Am J Trop Med Hyg 74: 1067–1073.
Qadri F, Svennerholm AM, Faruque AS, Sack RB, 2005. Enterotoxigenic Escherichia coli in developing countries: epidemiology, microbiology, clinical features, treatment, and prevention. Clin Microbiol Rev 18: 465–483.
United Nations International Children's Emergency Fund, 2011. Urban Water Challenges in Bangladesh. Available at: http://www.unicef.org/bangladesh/Urban_water_challenges_in_Bangladesh.pdf. Accessed May 4, 2014.
Clasen T, Saeed TF, Boisson S, Edmondson P, Shipin O, 2007. Household water treatment using sodium dichloroisocyanurate (NaDCC) tablets: a randomized, controlled trial to assess microbiological effectiveness in Bangladesh. Am J Trop Med Hyg 76: 187–192.
Sirajul Islam M, Brooks A, Kabir MS, Jahid IK, Shafiqul Islam M, Goswami D, Nair GB, Larson C, Yukiko W, Luby S, 2007. Faecal contamination of drinking water sources of Dhaka city during the 2004 flood in Bangladesh and use of disinfectants for water treatment. J Appl Microbiol 103: 80–87.
World Health Organization, 2012. Mortality and Burden of Disease from Water and Sanitation. Available at: http://www.who.int/gho/phe/water_sanitation/burden/en/. Accessed May 4, 2014.
World Health Organization, 2012. Inadequate Water, Sanitation and Hygiene in Low- and Middle-Income Countries. Available at: http://apps.who.int/gho/data/view.main.INADEQUATEWSHv?lang=en. Accessed May 4, 2014.
World Health Organization, 2008. Progress on Drinking Water and Sanitation: Special Focus on Sanitation. Available at: http://www.who.int/water_sanitation_health/monitoring/jmp2008/en/. Accessed May 4, 2014.
Arnold BF, Colford JM, 2007. Treating water with chlorine at point-of-use to improve water quality and reduce child diarrhea in developing countries: a systematic review and meta-analysis. Am J Trop Med Hyg 76: 354–364.
Clasen T, Edmondson P, 2006. Sodium dichloroisocyanurate (NaDCC) tablets as an alternative to sodium hypochlorite for the routine treatment of drinking water at the household level. Int J Hyg Environ Health 209: 173–181.
Clasen T, Schmidt WP, Rabie T, Roberts I, Cairncross S, 2007. Interventions to improve water quality for preventing diarrhoea: systematic review and meta-analysis. BMJ 334: 782.
Wright J, Gundry S, Conroy R, 2004. Household drinking water in developing countries: a systematic review of microbiological contamination between source and point-of-use. Trop Med Int Health 9: 106–117.
Lantagne DS, 2008. Sodium hypochlorite dosage for household and emergency water treatment. J Am Water Works Ass 100: 106–119.
Levy K, Anderson L, Robb KA, Cevallos W, Trueba G, Eisenberg JN, 2014. Household effectiveness vs. laboratory efficacy of point-of-use chlorination. Water Res 54: 69–77.
Schauer S, Sommer R, Farnleitner AH, Kirschner AK, 2012. Rapid and sensitive quantification of Vibrio cholerae and Vibrio mimicus cells in water samples by use of catalyzed reporter deposition fluorescence in situ hybridization combined with solid-phase cytometry. Appl Environ Microbiol 78: 7369–7375.
George CM, Monira S, Sack DA, Rashid MU, Saif-Ur-Rahman KM, Mahmud T, Rahman Z, Mustafiz M, Bhuyian SI, Winch PJ, Leontsini E, 2016. Randomized controlled trial of hospital-based hygiene and water treatment intervention (CHoBI7) to reduce cholera. Emerg Infect Dis 22: 233.
Ercumen A, Naser AM, Unicomb L, Arnold BF, Colford JM Jr, Luby SP, 2015. Effects of source-versus household contamination of tubewell water on child diarrhea in rural Bangladesh: a randomized controlled trial. PLoS One 10: e0121907.
Huq A, Haley BJ, Taviani E, Chen A, Hasan NA, Colwell RR, 2012. Detection, isolation, and identification of Vibrio cholerae from the environment. Curr Protoc Microbiol 6: 6A.5.
Haque R, Mondal D, Kirkpatrick BD, Akther S, Farr BM, Sack RB, Petri WA Jr, 2003. Epidemiologic and clinical characteristics of acute diarrhea with emphasis on Entamoeba histolytica infections in preschool children in an urban slum of Dhaka, Bangladesh. Am J Trop Med Hyg 69: 398–405.
Chowdhury F, Rahman MA, Begum YA, Khan AI, Faruque AS, Saha NC, Baby NI, Malek MA, Kumar AR, Svennerholm AM, Pietroni M, 2011. Impact of rapid urbanization on the rates of infection by Vibrio cholerae O1 and enterotoxigenic Escherichia coli in Dhaka, Bangladesh. PLoS Negl Trop Dis 5: e999.
Faruque SM, Sack DA, Sack RB, Colwell RR, Takeda Y, Nair GB, 2003. Emergence and evolution of Vibrio cholerae O139. Proc Natl Acad Sci USA 100: 1304–1309.
|Past two years||Past Year||Past 30 Days|
|Full Text Views||588||177||5|
Household members of cholera patients are at a 100 times higher risk of cholera infections than the general population because of shared contaminated drinking water sources and secondary transmission through poor household hygiene practices. In this study, we investigated the bactericidal concentration of free chlorine required to inactivate Vibrio cholerae in household drinking water in Dhaka, Bangladesh. In laboratory experiments, we found that the concentrations of free chlorine required to inactivate 105 colony-forming units (CFU)/mL of V. cholerae serogroups O1 and O139 were 0.1 mg/L and 0.2 mg/L, respectively. The concentration of free chlorine generated by a single chlorine tablet (sodium dichloroisocyanurate [33 mg]) after a 30-minute reaction time in a 10-L sealed vessel containing Dhaka city municipal supply water was 1.8 mg/L; and the concentration declined to 0.26 mg/L after 24 hours. In field measurements, water collected from 165 households enrolled in a randomized controlled trial (RCT) of a chlorine and handwashing with soap intervention (Cholera-Hospital-Based-Intervention-for-7-Days [CHoBI7]), we observed significantly higher free chlorine concentrations in the 82 intervention arm households (mean = 1.12 mg/L, standard deviation [SD] = 0.52, range = 0.07–2.6 mg/L) compared with the 83 control households (0.017 mg/L, SD = 0.01, range = 0–0.06 mg/L) (P < 0.001) during spot check visits. These findings suggest that point-of-use chlorine tablets present an effective approach to inactivate V. cholerae from drinking water in households of cholera patients in Dhaka city. This result is consistent with the findings from the RCT of CHoBI7 which found that this intervention led to a significant reduction in symptomatic cholera infections among household members of cholera patients and no stored drinking water samples with detectable V. cholerae.
Financial support: This research was supported by the Center for Global Health at Johns Hopkins University and the National Institute of Allergy and Infectious Diseases, National Institutes of Health. icddr,b thanks the governments of Australia, Bangladesh, Canada, Sweden, and United Kingdom for providing core/unrestricted support.
Authors' addresses: Mahamud-ur Rashid, Shirajum Monira, Md. Toslim Mahmud, Zillur Rahman, Munshi Mustafiz, K. M. Saif-Ur-Rahman, Tahmina Parvin, Sazzadul Islam Bhuyian, Fatema Zohura, Farzana Begum, Shwapon Kumar Biswas, Shamima Akhter, and Munirul Alam, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh, E-mails: email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, and email@example.com. Christine Marie George, Xiaotong Zhang, David Sack, and R. Bradley Sack, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, E-mails: firstname.lastname@example.org, email@example.com, firstname.lastname@example.org, and email@example.com.