title: Cholera Outbreaks in Urban Bangladesh In 2011.
abstract: BACKGROUND
  In 2011, a multidisciplinary team investigated two diarrhoea outbreaks affecting urban Bangladeshi communities from the districts of Bogra and Kishorganj to identify etiology, pathways of transmission, and factors contributing to these outbreaks.
  
  
  METHODS
  We defined case-patients with severe diarrhoea as residents from affected communities admitted with ≥3 loose stools per day. We listed case-patients, interviewed and examined them, and collected rectal swabs. We visited the affected communities to explore the water and sanitation infrastructure. We tested the microbial load of water samples from selected case household taps, tube wells, and pump stations. We conducted anthropological investigations to understand community perceptions regarding the outbreaks.
  
  
  RESULTS
  We identified 21 case-patients from Bogra and 84 from Kishorganj. The median age in Bogra was 23 years, and 21 years in Kishorganj. There were no reported deaths. We isolatedVibrioin 29% (5/17) of rectal swabs from Bogra and in 40% (8/20) from Kishorganj. We foundVibrioin 1/8 tap water samples from Bogra and in both of the samples from Kishorganj. We did not findVibrioin water samples from pumps or tube wells in either outbreak. Ground water extracted through deep tube wells was supplied intermittently through interconnected pipes without treatment in both areas. We found leakages in the water pipes in Bogra, and in Kishorganj water pipes passed through open sewers.
  
  
  CONCLUSIONS
  The rapid onset of severe diarrhoea predominantly affecting adults and the isolation of cholera in rectal swabs confirmed that these outbreaks were caused byVibrio cholerae. The detection ofVibrioin water samples organisms from taps but not from pumps or tube wells, suggested contamination within the pipes. Safe water provision is difficult in municipalities where supply is intermittent, and where pipes commonly leak. Research to develop and evaluate water purification strategies could identify appropriate approaches for ensuring safe drinking water in resource-poor cities.
authors.affiliation: Centre for Communicable Diseases (CCD), International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) ; Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, Bangladesh.
authors.forename: Farhana
authors.initials: F
authors.lastname: Haque
authors.affiliation: Centre for Communicable Diseases (CCD), International Centre for Diarrheal Disease Research, Bangladesh (icddr,b).
authors.forename: M Jahangir
authors.initials: MJ
authors.lastname: Hossain
authors.affiliation: Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, Bangladesh.
authors.forename: Subodh Kumar
authors.initials: SK
authors.lastname: Kundu
authors.affiliation: Centre for Communicable Diseases (CCD), International Centre for Diarrheal Disease Research, Bangladesh (icddr,b).
authors.forename: Abu Mohd
authors.initials: AM
authors.lastname: Naser
authors.affiliation: Institute of Epidemiology, Disease Control and Research (IEDCR), Dhaka, Bangladesh.
authors.forename: Mahmudur
authors.initials: M
authors.lastname: Rahman
authors.affiliation: Centre for Communicable Diseases (CCD), International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) ; Global Disease Detection and Emergency Response, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA.
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Luby
keywords: Bangladesh; Cholera; Outbreak; Urban