Transmission of hepatitis C virus in dialysis units: A systematic review of reports on outbreaks

Background: Hepatitis C virus (HCV) outbreaks among patients on hemodialysis are still an important health concern all over the world. Aims: We performed a systematic review of reports on HCV outbreaks within dialysis units of developed and less-developed countries (between 1992 and 2015) to evaluate risk factors and practices associated with patientto- patient transmission of HCV in this setting. Methods: The research was performed using the PubMed Database and the Outbreak Database; studies were selected according to the PRISMA algorithm. Inclusion criteria were established before the papers were retrieved in order to avoid selection biases. Results: 36 papers reported on 45 outbreaks that involved 335 unique patients on maintenance hemodialysis; no fatal cases were detected. Nosocomial transmission of HCV was confirmed by phylogenetic analysis in most (n = 31; 69%) reports. Sharing contaminated hemodialysis machines and multidose vials (heparin or saline solution) was suggested responsible for HCV transmission in 8 (18%) and 6 (13%) outbreaks, respectively. Breaches in environmental cleaning and disinfection practices, and failures in medication preparation and administration practices was considered in 29 (65%) outbreaks; however, the exact mechanism of transmission of HCV could not be ascertained in each facility where an outbreak occurred. Conclusions: Our systematic review of reports on hepatitis C virus outbreaks shows that, although the full extent of HCV transmission in dialysis units is unknown, outbreaks continue to occur. Full compliance to standard/ specific infection control procedures and routine serologic screening for HCV antibody play a pivotal role for preventing the transmission of HCV within hemodialysis units.