Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Patient-to-patient transmission of hepatitis C virus (HCV) during colonoscopy diagnosis | González-Candelas et al. Virology Journal 2010 7 217 http content 7 1 217 VIROLOGY JOURNAL RESEARCH Open Access Patient-to-patient transmission of hepatitis C virus HCV during colonoscopy diagnosis 2 2 2 Fernando González-Candelas Silvia Guiral Rosa Carbó Ana Valero Hermelinda Vanaclocha Francisco González2 Maria Alma Bracho1 3 4 Abstract Background No recognized risk factors can be identified in 10-40 of hepatitis C virus HCV -infected patients suggesting that the modes of transmission involved could be underestimated or unidentified. Invasive diagnostic procedures such as endoscopy have been considered as a potential HCV transmission route although the actual extent of transmission in endoscopy procedures remains controversial. Most reported HCV outbreaks related to nosocomial acquisition have been attributed to unsafe injection practices and use of multi-dose vials. Only a few cases of likely patient-to-patient HCV transmission via a contaminated colonoscope have been reported to date. Nosocomial HCV infection may have important medical and legal implications and therefore possible transmission routes should be investigated. In this study a case of nosocomial transmission of HCV from a common source to two patients who underwent colonoscopy in an endoscopy unit is reported. Results A retrospective epidemiological search after detection of index cases revealed several potentially infective procedures sample blood collection use of a peripheral catheter anesthesia and colonoscopy procedures. The epidemiological investigation showed breaches in colonoscope reprocessing and deficiencies in the recording of valuable tracing data. Direct sequences from the NS5B region were obtained to determine the extent of the outbreak and cloned sequences from the E1-E2 region were used to establish the relationships among intrapatient viral populations. Phylogenetic analyses of individual sequences from viral populations infecting the three patients .