November 20, 2012
Hepatitis C virus (HCV) infects the liver. Once HCV becomes established in this organ it causes inflammation. Over a period of years, this leads to increasing dysfunction and liver injury. If left untreated, HCV-related liver damage leads to poor health and serious complications, including liver failure, liver cancer and in some cases death. The risk for developing such complications is greater among people who are co-infected with both HIV and HCV.
In high-income countries such as Canada, Australia, the United States and Western Europe, screening of the blood supply has virtually eliminated transmission of HCV via blood transfusions. In these countries, HCV is now usually transmitted in the following ways:
The Public Health Agency of Canada estimates that HCV infections are several times more common among Aboriginal people compared to non-Aboriginal people. Young Aboriginal people are at particularly high risk for HCV. Most new HCV infections among Aboriginal people appear to be caused by sharing contaminated equipment for injecting street drugs.
Researchers in the cities of Vancouver and Prince George have been engaged in a study with young Aboriginal people called the Cedar Project. As part of this study, participants aged 14 to 30 years, most of whom live in the downtown areas of the two cities and all of whom smoke or inject street drugs are screened for eligibility. An Aboriginal study coordinator explains the purpose of the study and the procedures involved and after discussion, seeks informed consent.
Once enrolled, participants are interviewed extensively and have blood drawn for HIV and HCV testing. Nurses provide counselling both before and after testing and participants are encouraged to return to the study site for their test results. Every six months participants return to the study site for further interviews and blood tests.
The researchers found that among young people who were new to injecting street drugs, rates of HCV infection were very high. In its report, the Cedar Project team made recommendations, which, if implemented, have great potential to stop the spread of harm caused by substance use and HCV infection. Furthermore, their findings and recommendations are likely useful for community-based and public health workers who are struggling to help Aboriginal people in other parts of Canada deal with addiction and HCV infection.
The Cedar Project enrolled 605 participants. However, the HCV sub-study recruited 148 participants who were HCV negative when they entered the study and our report focusses on these people.
The average profile of the 148 participants at the start of the study was as follows:
The substance use of participants in the past six months was as follows:
On average, participants were in the study for 2.5 years.
Among young people who were new to injecting drugs, 38% became HCV positive within the first year of the study. By the third year of the study this figure had risen to more than 50%.
Other factors linked to an increased risk for HCV infection were as follows:
Unexpectedly, participants who had been injecting for many years had a relatively low risk for HCV. This may be because they survived and could enter the study while people with long-term HCV infection may have succumbed to the complications caused by this infection and were therefore unavailable to enter the study.
No comments have been made.