Epidemiology of Acute Hepatitis C Infection in Canada Results from the Enhanced Hepatitis Strain Surveillance System (EHSSS)

Hepatitis C is one of the major causes of liver failure and transplant in the developed world.

The hepatitis C virus (HCV), which causes Hepatitis C, is transmitted through blood contact with someone
infected with hepatitis C. In Canada, recreational injection drug use (IDU) continues to be the
predominant risk factor for HCV acquisition (due to sharing of needles, syringes, and other injection
equipment), and is associated with 70-80% of newly acquired HCV cases in Canada. In larger Canadian
cities, the second largest risk factor is travel or residence to a HCV-endemic region because of the higher
rate of health care-acquired HCV infections in these regions.  Sharing of equipment for inhalation drug
use (e.g. crack pipes, straws, etc.) may also be associated with HCV infection. Sexual and perinatal
(mother-to-child) transmission occurs uncommonly.  Elevated risk is associated with tattooing or body
piercing with contaminated equipment, the sharing of personal hygiene items (e.g. razors, toothbrushes)
with someone infected with HCV, or occupational blood exposure. While there have been cases of HCV
transmission via contaminated blood transfusions in the past, the enhanced screening procedures of
Canada’s blood supply since 1990 has virtually eliminated this risk.  Currently, there is no vaccine for
HCV, although vaccine research is in progress.

Recent estimates indicate that as of December 2007, approximately 242,500 Canadians had been infected
with HCV, corresponding to a prevalence rate of approximately 0.7% of the total population.  In the
United States, combined data from 1999 through 2002 from the National Health and Nutrition
Examination Survey estimated the prevalence of chronic HCV infection to be 1.3%.  Recently published
estimates from the United Kingdom suggest that approximately 0.4% of the population aged 15-59 were
chronically infected with HCV, and a 2006 study in Australia estimated that 197,300 people were
chronically infected in that country, corresponding to a prevalence rate of approximately 0.9%.

The World Health Organization estimates that 2-3% of the world’s population (approximately 123-170 million
people) is infected with HCV.  Countries of highest endemicity are located in Africa, Latin America,
and Central and Southeast Asia.  In these regions, HCV prevalence rates of 5% to 10% are frequently
reported.

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STI and HCV Surveillance and Epidemiology Section
Community Acquired Infections Division
Centre for Communicable Disease and Infection Control
Tunney’s Pasture, Postal Locator: 0603B
Ottawa, Ontario K1A 0K9