Epidemiologic and Molecular Investigation of Outbreaks of Hepatitis C Virus Infection on a Pediatric Oncology Service

Epidemiologic and Molecular Investigation of Outbreaks of Hepatitis C Virus Infection on a Pediatric Oncology Service

Anders Widell, MD, PhD;
Bertil Christensson, MD, PhD;
Thomas Wiebe, MD, PhD;
Claes Schalén, MD, PhD;
Hans Bertil Hansson, MD;
Tobias Allander, MD, PhD; and
Mats A.A. Persson, MD, PhD

From University Hospital and the Regional Center for Communicable Disease Control, Malmö, Sweden; University Hospital, Lund, Sweden; and Karolinska Hospital, Stockholm, Sweden.

Abstract

Background: Despite screening of blood donors, hepatitis C virus (HCV) infection can occur in patients who receive multiple transfusions.

Objective: To clarify mechanisms of nosocomial transmission of HCV.

Design: Epidemiologic and molecular analyses of hepatitis C outbreaks.

Setting: Pediatric oncology ward.

Patients: Children with cancer.

Measurements: Epidemiologic analysis, HCV RNA detection, genotyping, and hypervariable region 1 (HVR1) sequencing.

Results: Ten cases of infection with acute HCV genotype 3a occurred between 1990 and 1993. Sequencing of HVR1 revealed three related strains. Despite an overhaul of hygiene procedures, a patient infected with genotype 1b generated nine subsequent infected patients in 1994. Several patients had high virus titers and strongly delayed anti-HCV antibody responses. All had permanent intravenous catheters. Multidose vials used for flushing or treatment had probably been contaminated during periods of overlapping treatment.

Conclusions: Contamination of multidose vials was the most likely mode of HCV transmission; therefore, use of such vials should be restricted. Rigorous adherence to hygiene routines remains essential to preventing transmission of bloodborne infections.

Article and Author Information

Acknowledgments: The authors thank Angela Magnusson and Ann-Christin Hammarlund from the Hospital Infection Control Unit for collecting basic data from the patients, Siv Månsson and Aster Beyene for assistance in performing the virologic analysis, and Patricia Ödman for assistance with the English language.
Grant Support: By the Swedish Medical Research Council (grant B96-16X-02865-29), the Swedish Cancer Society, the Medical Faculty of Lund University, the Alfred Ö sterlund Foundation, the Swedish Research Committee for Engineering and Technological Sciences, and the Nanna Svartz Fund.
Requests for Reprints: Anders Widell, MD, PhD, Department of Medical Microbiology, University Hospital, Malmö, S-20502 Malmö, Sweden.
Current Author Addresses: Dr. Widell: Department of Medical Microbiology, University Hospital, Malmö, S-20502 Malmö, Sweden.
Dr. Christensson: Department of Infectious Diseases, University Hospital Lund, S-22185 Lund, Sweden.
Dr. Wiebe: Department of Pediatrics, University Hospital Lund, S-22185 Lund, Sweden.
Dr. Schalén: Department of Hospital Infection Control, University Hospital Lund, S-22185 Lund, Sweden.
Dr. Hansson: Regional Center for Communicable Disease Control, University Hospital, Malmö, S-20502 Malmö, Sweden.
Dr. Allander: Department of Clinical Microbiology, University Hospital, S-75185 Uppsala, Sweden.
Dr. Persson: Department of Medicine, Karolinska Hospital, S-17176, Stockholm, Sweden.