Researchers led by scientists at the Health Research Board have estimated that more than 9,317 of drug users with hepatitis C suffer from chronic forms of the disease.
The research team said there could also be a significant number of undiagnosed cases of hepatitis C among recent immigrants here. They said that although asylum seekers are routinely offered infectious disease testing, there is no systematic testing for other migrants.
They estimate that, based on the prevalence of the disease in the country of birth of immigrants, there are likely to be more than 10,000 cases of hepatitis C among the non-Irish national population of more than 766,000 people.
The most common form of infection of hepatitis C is through injecting drugs, usually as a result of sharing contaminated needles.
The research, which examined records of all drug users who entered drug treatment for the first time between 1991 and 2014, found incidence of the disease peaked in 1997. Researchers estimate almost 30% of drugs users with hepatitis C have had the disease for over 20 years. However, the figures do not take account of drug users who may have died or who were successfully treated, they point out.
A national treatment programme established in 2014 offering direct acting antivirals to individuals who have tested positive for the disease reported that 138 drug users were successfully treated up to August 2016.
Anne Marie Carew of the Health Research Board, one of the author’s of the study, said the incidence of hepatitis C is now on the decrease with statutory notification of the disease having declined significantly since 2012.
Other records indicate that 937 drug users who were infected with hepatitis C died between 1998 and 2014.
Separately, out of more than 1,700 people infected with hepatitis C through contaminated blood products before the introduction of routine screening in the early 1990s, approximately 390 were still alive and chronically infected in 2013.