To stop transmission of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in association with myocardial perfusion imaging (MPI) at a cardiology clinic.

Outbreak investigation and quasispecies analysis of HCV hypervariable region 1 genome.

Outpatient cardiology clinic.

Patients undergoing MPI.

Case patients met definitions for HBV or HCV infection. Cases were identified through surveillance registry cross-matching against clinic records and serological screening. Observations of clinic practices were performed.

During 2012–2014, 7 cases of HCV and 4 cases of HBV occurred in 4 distinct clusters among patients at a cardiology clinic. Among 3 case patients with HCV infection who had MPI on June 25, 2014, 2 had 98.48% genetic identity of HCV RNA. Among 4 case patients with HCV infection who had MPI on March 13, 2014, 3 had 96.96%–99.24% molecular identity of HCV RNA. Also, 2 clusters of 2 patients each with HBV infection had MPI on March 7, 2012, and December 4, 2014. Clinic staff reused saline vials for >1 patient. No infection control breaches were identified at the compounding pharmacy that supplied the clinic. Patients seen in clinic through March 27, 2015, were encouraged to seek testing for HBV, HCV, and human immunodeficiency virus. The clinic switched to all single-dose medications and single-use intravenous flushes on March 27, 2015, and no further cases were identified.

This prolonged healthcare-associated outbreak of HBV and HCV was most likely related to breaches in injection safety. Providers should follow injection safety guidelines in all practice settings.

In November and December 2012, 6 patients at a hemodialysis clinic were given a diagnosis of new hepatitis C virus (HCV) infection.

To investigate the outbreak to identify risk factors for transmission.

A case patient was defined as a patient who was HCV-antibody negative on clinic admission but subsequently was found to be HCV-antibody positive from January 1, 2008, through April 30, 2013. Patient charts were reviewed to identify and describe case patients. The hypervariable region 1 of HCV from infected patients was tested to assess viral genetic relatedness. Infection control practices were evaluated via observations. A forensic chemiluminescent agent was used to identify blood contamination on environmental surfaces after cleaning.

Eighteen case patients were identified at the clinic from January 1, 2008, through April 30, 2013, resulting in an estimated 16.7% attack rate. Analysis of HCV quasispecies identified 4 separate clusters of transmission involving 11 case patients. The case patients and previously infected patients in each cluster were treated in neighboring dialysis stations during the same shift, or at the same dialysis station on 2 consecutive shifts. Lapses in infection control were identified. Visible and invisible blood was identified on multiple surfaces at the clinic.

Epidemiologic and laboratory data confirmed transmission of HCV among numerous patients at the dialysis clinic over 6 years. Infection control breaches were likely responsible. This outbreak highlights the importance of rigorous adherence to recommended infection control practices in dialysis settings.

Infect. Control Hosp. Epidemiol. 2016;37(2):125–133