1. Epidemiology of hepatitis C in Ireland
2018 data are provisional (data completeness will improve on validation)
Niamh Murphy & Dr Kevin Kelleher, April 2019

2. Hepatitis C virus (1) Hepatitis C Virus first identified in 19891
Most commonly transmitted through blood1
Routine screening of blood donations in Ireland started in 1991
Approximately 1,700 people were infected through contaminated blood/blood products prior to this2
Most new cases of hepatitis C in developed countries like Ireland are in people who inject drugs and migrants from higher endemicity countries1
Hepatitis C can also be transmitted sexually and from an infected mother to her baby - less common, but risk higher if HIV positive1
Most cases are initially asymptomatic or mildly symptomatic (acute infection rarely detected), but approx. 75% of those infected develop chronic infection3,4

3. Hepatitis C virus (2)
Chronic infection can cause liver inflammation, fibrosis, cirrhosis, liver cancer (HCC), liver failure and death3,4
10-20% of chronically infected cases develop cirrhosis after years4
Of those with cirrhosis, approximately 4% progress to decompensated liver disease annually, % develop HCC annually and approximately 80% of those with HCC die annually3
Disease progression is faster in males, people who were older at infection, those who are co-infected with HIV or hepatitis B and those who consume high levels of alcohol4
Disease progression is also influenced by metabolic (high BMI, diabetes) and host genetic factors4

5. Worldwide prevalence of hepatitis C infection5

6. Epidemiology of hepatitis C in Ireland
Hepatitis C became notifiable in 2004
: 15,266 cases notified, highest number in 2007 (n=1,537), significant decrease in recent years – 589 cases notified in 2018
Notifications include some (but not all) cases diagnosed before 2004 and not previously notified, and some duplicates (full names missing ~18%)
2012: case definitions altered to explicitly exclude cases known to be resolved (no longer viraemic). Prior to mid-2010, laboratory results included in HCV notifications were frequently insufficient to distinguish chronically infected and resolved cases
67% of cases notified were male
Age at notification : median 35 years, mean 37 years
Age at notification has increased over time
Median age: – 31 years, 2018 – 41 years
Mean age: – 33 years, 2018 – 42 years
Risk factor data collected (available for 51% of cases)
79% of the cases with risk factor data were people who inject drugs
Where country of birth was known, 1/3 cases were born in hepatitis C endemic countries (>2% anti-HCV prevalence)

7. Number of notifications of hepatitis C in Ireland, 2004-2018 by sex and median age
*Case definition changed in 2012 – cases known to be resolved excluded from notification

8. Age and sex specific notification rates per 100,000 for hepatitis C in Ireland, 2018

9. Trends in age-specific hepatitis C notification rates per 100,000 population in Ireland, 2004-2018

10. Trends in sex-specific hepatitis C notification rates per 100,000 population in Ireland, 2004-2018

11. Hepatitis C notification rates per 100,000 population by HSE area in Ireland, 2004-2018

12. Most likely risk factor (%) for cases of hepatitis C notified in Ireland, (where data available, n=5,823, 51%)

13. Most likely risk factor (%) for cases of hepatitis C notified in Ireland, 2018 (where data available, n=251, 43%)

14. Hepatitis C risk factor trends in Ireland, 2007-2018

15. Hepatitis C cases in Ireland identified as men who have sex with men (MSM), by HIV/other recent STI status,
*Gonorrhoea, syphilis, chlamydia, lymphogranuloma venereum or genital herpes simplex in the same year as hepatitis C notification or in the year prior to hepatitis C notification, HIV status is as of year of hepatitis C diagnosis

16. Country/region of birth (%) for cases of hepatitis C notified in Ireland, (where data available, n=2,829, 25%)

17. Country/region of birth (%) for cases of hepatitis C notified in Ireland, 2018 (where data available, n=245, 42%)

18. Most likely risk factor by country/region of birth for cases of hepatitis C notified in Ireland, (where country of birth data available, n=245, 42%)

19. Estimates of the prevalence of hepatitis C in Ireland: 3 methods
1. NVRL diagnoses and HPSC notifications
~10,000 individuals alive & diagnosed with chronic hepatitis C by the end of 20096
Add adjusted HPSC notifications to end 2018
~15,000 alive & diagnosed with chronic hepatitis C
Level of under diagnosis unknown
If 75% of cases diagnosed: ~20,000 cases
If 50% of cases diagnosed: ~30,000 cases
Limitations:
Did not adjust for hepatitis C treatment – low uptake/SVR at time of study, ~4,000 patients now treated and cured. The level of under diagnosis in Ireland is unknown, estimates used for death rate (13%) may be too low, estimate used for chronicity (75%) may be too high, duplicate notification numbers may be underestimated
Did not adjust for hepatitis C treatment or deaths in PWID, migrants in Ireland may have a lower HCV prevalence than the population in their country of birth. A proportion of infected migrants may be already included in PWID figures.
No risk factor information, potential underestimate as high risk specimen sources excluded. Study based on specimens from 2014/2015 – over 3,000 patients treated and cured between 2016 and 2018.
2. HRB data7
9,317 PWID chronically infected with HCV end 2014
3. NVRL general population residual samples tested for hepatitis C8
Weighted prevalence chronic hepatitis C :
19,606 (0.6%)
adults chronically infected
with HCV
95% CI ~14,000-28,000
( % of adults)
Migrants
Census 2016 data by country of birth * published HCV prevalence data
~8,500
+ other risk groups
~19,000-20,000

20. Studies of hepatitis C prevalence in different sub-populations in Ireland
Injecting drug users
Studies of injecting drug users (mostly heroin) in Ireland, between 1992 and 2006: hepatitis C antibody (anti-HCV) prevalence in this population 52-84%9-18
2011 prison study found that 54% of prisoners with a history of injecting heroin were anti-HCV positive and 41.5% of prisoners with a history of injecting any drugs were anti-HCV positive18,19
Further details on hepatitis C in drug users described in a 2018 report on drug-related bloodborne viruses in Ireland19
Antenatal females: Universal HCV screening studies in 2 large maternity hospitals in Dublin: 0.7% & 0.9% anti-HCV positive, 0.4 & 0.6% RNA positive 20, 21
New blood donors: Irish Blood Transfusion Service: 0.014% of new donors tested 1997 to 2017 were anti-HCV positive (personal communication: IBTS)
Asylum seekers: Balseskin reception centre: 1% of those tested, under the voluntary health screening programme, between 2004 and 2012, were positive for chronic HCV infection22

21. Hepatitis C anti-viral treatment
Highly effective direct acting antiviral (DAA) medicines for the treatment of hepatitis C have been available in Ireland since late
These treatments eradicate the virus in over 95% of cases23
A HSE National Hepatitis C Treatment Programme was established in Ireland in 2016
This programme aims to provide treatment for all people living with hepatitis C in Ireland
Improvements in screening, referral to appropriate services and treatment uptake are needed19
Hepatitis C screening guidelines were developed in
With improved case ascertainment, referral and treatment uptake, hepatitis C could become a rare disease in Ireland

22. References (1)
World Health Organization: Guidelines for the screening, care and treatment of persons with hepatitis C infection. Geneva; April 2014
Health Protection Surveillance Centre. National Hepatitis C database Report. Available at:
Global Burden of Hepatitis C Working Group: Global burden of disease (GBD) for hepatitis C. J Clin Pharmacol 2004, 44:20-29.
Westbrook RH, Dusheiko G. Natural history of hepatitis C. J Hepatol Nov;61(1 Suppl):S58-68.
Map: CDC Health Information for International Travel
Thornton L, Murphy N, Jones L, Connell J, Dooley S, Gavin S, Hunter K, Brennan A. Determination of the burden of hepatitis C virus infection in Ireland. Epidemiol Infect Aug;140(8):1461-8
Carew AM, Murphy N, Long J, Hunter K, Lyons S, Walsh C, Thornton L. Incidence of hepatitis C among people who inject drugs in Ireland. Hepatol Med Policy 2017,2:7
Garvey P, O’Grady B, Franzoni G, Bolger M, Irwin Crosby K, Connell J, Burke D, De Gascun, C, Thornton L. Hepatitis C virus seroprevalence and prevalence of chronic infection in the adult population in Ireland: a study of residual sera, April 2014 to February Euro Surveill. 2017;22(30):pii=30579
Smyth R, Keenan E, Dorman A, O’Connor J: Hepatitis C infection among injecting drug users attending the National Drug Treatment Centre. Ir J Med Sci 1995, 164(4):
Smyth BP, Keenan E, O’Connor JJ: Bloodborne viral infection in Irish injecting drug users. Addiction 1998, 93(11):
Smyth BP, Keenan E, O’Connor JJ: Evaluation of the impact of Dublin’s expanded harm reduction programme on prevalence of hepatitis C among short-term injecting drug users. J Epidemiol Community Health 1999, 53:
Cullen W, Bury G, Barry J and O’Kelly F. Drug users attending general practice in the Eastern Regional Health Authority area. IMJ 2000, 93(7): 214–217
Grogan L, Tiernan M, Geoghegan N, Smyth BP, Keenan E: Bloodborne virus infections among drug users in Ireland: a retrospective cross-sectional survey of screening, prevalence, incidence and hepatitis B immunisation uptake. Ir J Med Sci 2005, 174(2):14-20

23. References (2)
Cullen W, Bury G, Barry J, O’Kelly FD: Hepatitis C infection among drug users attending general practice. Ir J Med Sci 2003, 172(3):123-27
Cullen W, Stanley J, Langton D, Kelly Y, Bury G: Management of hepatitis C among drug users attending general practice in Ireland: Baseline data from the Dublin area hepatitis C in general practice initiative. Eur J Gen Pract 2007, 13:5-12
Long, Jean (2006) Blood-borne viral infections among injecting drug users in Ireland, 1995 to Overview 4. Health Research Board, Dublin
Allwright S, Bradley F, Long J, Barry J, Thornton L and Parry JV (2000) Prevalence of antibodies to hepatitis B, hepatitis C and HIV and risk factors in Irish prisoners: results of a national cross-sectional survey. BMJ, 321: 78–82
Drummond A, Codd M, Donnelly N, McCausland D, Mehegan J, Daly L, Kelleher C: Study on the prevalence of drug use, including intravenous drug use, and blood-borne viruses among the Irish prisoner population. Dublin: National Advisory Committee on Drugs and Alcohol; 2014
Health Protection Surveillance Centre (HPSC). Drug-related bloodborne viruses in Ireland, Available from:
Martyn F, Phelan O, O'Connell M. Hepatitis C: is there a case for universal screening in pregnancy? Ir Med J May;104(5):144-6
Lambert J, Jackson V, Coulter-Smith S, Brennan M, Geary M, Kelleher TB, O'Reilly M, Grundy K, Sammon N, Cafferkey M. Universal antenatal screening for hepatitis C. Ir Med J May;106(5):136-9
Brennan M, Boyle PJ, O'Brien AM, Murphy K. Health of Asylum seekers - are we doing enough? ICGP Forum magazine, November 2013
AASLD-IDSA HCV Guidance Panel. Hepatitis C Guidance 2018 Update: AASLD-IDSA. Recommendations for Testing, Managing, and Treating Hepatitis C Virus Infection. Clin Infect Dis Oct 30;67(10): Available from:
Department of Health (2017). Hepatitis C Screening (NCEC National Clinical Guideline No. 15). Available at:

24. Acknowledgements
Departments of Public Health in all HSE areas: SPHMs, SMOs, Surveillance Scientists, IPCNs, Administration staff
Notifiers: Laboratory Directors and their staff, and Clinicians
Dr Lelia Thornton, Hepatitis SPHM in HPSC (retired 2018)
Dr Patricia Garvey, Surveillance Scientist, HPSC
Dr Aisling O’ Leary, National Centre for Pharmacoeconomics, St James’s Hospital
Michelle Tait, former Programme Manager National Hepatitis C Treatment Programme
Anne-Marie Carew, Health Research Board