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.