Long, Jean
(2008)
First reports of risk factors from hepatitis C surveillance.
Drugnet Ireland,
Issue 27, Autumn 2008,
p. 21.
Hepatitis C is one the most common blood-borne viral infections among injecting drug users and is transmitted through contact with the blood of an infected person. The main routes of transmission are mother-to-baby, unsafe injections, transfusion of blood and blood products, and unsterile tattooing and skin piercing. Murphy and Thornton reported that 1,558 cases of hepatitis C were recorded in 2007 (Table 1), compared to 1,130 cases in 2004, and 85 cases of hepatitis ‘type unspecified’ in 2003.1
Table 1 Number of cases of hepatitis C and age-standardised rates (ASR) per 100,000 population, 2004–2007ear Number of cases ASR per 100,000
|
Year
|
Number of cases
|
ASR
|
|
2004
|
1130
|
25.5
|
|
2005
|
1433
|
33.4
|
|
2006
|
1222
|
28.5
|
|
2007
|
1558
|
36.8
|
Source: Murphy and Thornton (2008)
Of the cases reported in 2007, 77% were notified by services in Dublin, Kildare and Wicklow and the remainder by services in HSE areas outside these counties. The authors calculated age-standardised hepatitis C rates per 100,000 of the population living in each former health board area for the years 2004 to 2007. The rate increased in all of those areas in 2007 compared to 2004, and was highest in the east (over 70 per 100,000) and lowest in the north west (at 10 per 100,000). Sixty-three per cent of hepatitis C cases reported were male. Of the cases for whom age was known, 92% were aged between 20 and 54 years.
An enhanced surveillance system for hepatitis C was introduced in Ireland in 2007. Enhanced surveillance is essential to identify risk factors and for planning prevention and treatment strategies. In 2007, 42% of newly reported hepatitis C cases had their risk factor status recorded (Table 2) (N Murphy, HPSC, personal communication, 2008). As expected, the majority of these cases (75.3%) reported injecting drug use as the main risk factor. Just over 5% of cases reported that they had been recipients of blood or blood products at some time in the past and, according to the HPSC, were late reports to the system.
Table 2 Number and percentage of hepatitis C cases reported to the HPSC, by risk factor status, 2007
|
|
Hepatitis C
|
|
|
2007
|
|
Risk factor status
|
n
|
%
|
|
Total number of cases
|
1558
|
|
|
|
|
|
|
Cases with reported risk factor data
|
658
|
42.2
|
|
Of which:
|
|
|
|
Injecting drug users
|
496
|
75.3
|
|
Recipients of blood/blood products
|
34
|
5.2
|
|
Other risk factors
|
89
|
13.5
|
|
No known risk factor identified by patient or doctor
|
39
|
5.9
|
|
|
|
|
|
Cases without reported risk factor data
|
900
|
57.8
|
Source: Unpublished data from the HPSC
Data from blood-borne viral prevalence studies between 1995 and 2005 indicate that around 70% of injecting drug users attending drug treatment tested positive for antibodies to the hepatitis C virus.2 Injecting practices and prison history were associated with hepatitis C status in some of these studies.
The National Immunisation Advisory Committee and the Department of Health and Children recommended significant changes to Ireland’s national childhood immunisation programme in 2008.3 These changes, published in the revised Immunisation guidelines for Ireland in August 2008, include the addition of a hepatitis B vaccine to the routine 5-in-1 childhood immunisation programme, which will now become a 6-in-1 programme. The Immunisation guidelines for Ireland 2002 recommended the hepatitis B vaccine for several high-risk groups only, including prisoners and injecting drug users, rather than for the child population. (Jean Long)
1. Murphy N and Thornton L (2008) Epidemiology of hepatitis C infection in Ireland. EPI-Insight, 9(7): 2–3.
2. Long (2006) Blood-borne viral infections among injecting drug users in Ireland, 1995 to 2005. HRB Overview Series 4. Dublin: Health Research Board.
3. Cotter S (2008) Changes to the Irish primary childhood immunisation programme. EPI- Insight, 9(8): 1.
4. National Immunisation Advisory Committee (2008) Immunisation guidelines for Ireland. 2008 edition. Dublin: Royal College of Physicians of Ireland
