title: Detection of Escherichia coli, Salmonella species, and Vibrio cholerae in tap water and bottled drinking water in Isfahan, Iran.
abstract: BACKGROUND
  The quality of drinking water has an important role in human infection and disease. This study was aimed at comparing polymerase chain reaction and culture in detecting Escherichia coli, Salmonella species and Vibrio cholera in tape water and bottled drinking water in various seasons in Isfahan province, Iran.
  
  
  METHODS
  A total of 448 water samples from tap water and bottled mineral water were taken over 6 months, from July 2010 to December 2010, and after filtration, samples were examined by culture and polymerase chain reaction methods for detection of Escherichia coli, Salmonella species, and Vibrio cholerae.
  
  
  RESULTS
  The culture method showed that 34 (7.58%), 4 (0.89%) and 3 (0.66%) of all 448 water samples were positive for Escherichia coli, Salmonella species, and Vibrio cholera, respectively. The uidA gene from Escherichia coli, IpaB gene from Salmonella species, and epsM gene from Vibrio cholera were detected in 38 (26.38%), 5 (3.47%), and 3 (2.08%) of 144 tap-water samples, respectively. Escherichia coli was detected in 8 (2.63%) of 304 samples of bottled drinking water from 5 companies. The water of southern part of Isfahan and company 5 had the highest prevalence of bacteria. The Escherichia coli water contamination was significantly higher (P < 0.05) in the hot seasons (July-August) than cold (November-December) seasons and in company 5 than other companies. There were significant differences (P < 0.05) for the prevalence of bacteria between the tap waters of southern part and tap waters of central part of Isfahan.
  
  
  CONCLUSIONS
  This study showed that the polymerase chain reaction assays can be an extremely accurate, fast, safe, sensitive and specific approach to monitor drinking water quality from purification facilities and bottled water companies. Also, our study confirmed the presence of Escherichia coli, Salmonella species, and Vibrio cholerae as water-borne pathogens in tap water and bottled drinking water of Isfahan, Iran. The present study showed the important public health problem in Isfahan, Iran.
authors.affiliation: Department of Microbiology, College of Veterinary Medicine, ShahreKord Branch, Islamic Azad University, P,O, Box: 166, ShahreKord, Iran. hamomtaz@yahoo.com.
authors.forename: Hassan
authors.initials: H
authors.lastname: Momtaz
authors.forename: Farhad Safarpoor
authors.initials: FS
authors.lastname: Dehkordi
authors.forename: Ebrahim
authors.initials: E
authors.lastname: Rahimi
authors.forename: Amin
authors.initials: A
authors.lastname: Asgarifar
mesh_terms: D004269:DNA, Bacterial / Q000032:analysis; D060766:Drinking Water / Q000382:microbiology*; D004784:Environmental Monitoring; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification; D006090:Gram-Negative Bacteria / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007492:Iran / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012475:Salmonella / Q000235:genetics / Q000302:isolation & purification; D012621:Seasons; D014734:Vibrio cholerae / Q000235:genetics / Q000302:isolation & purification; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial; D060766:Drinking Water