Laboratory reports of hepatitis C infection in England and Wales
A total of 2422 cases of hepatitis C infection were reported to the Health Protection Agency Centre for Infections in the first quarter of 2009, higher than the 2142 cases reported in the first quarter of 2008 (table 2). The majority of reports were as in previous quarters amongst those aged 25-44 years. Sixty percent (1452/2404) of cases were in this age group. The ratio of males to females is 1.8:1.
Table 2. Laboratory reports of hepatitis C infection in England and Wales: January to March, 2009
| Age group | Male | Female | Unknown | Total |
| 1-4 years | 1 | 1 | – | 2 |
| 5-9 years | 1 | – | – | 1 |
| 10-14 years | – | – | 1 | 1 |
| 15-24 years | 77 | 92 | 20 | 189 |
| 25-34 years | 409 | 262 | 33 | 704 |
| 35-44 years | 560 | 221 | 17 | 798 |
| 45-54 years | 325 | 153 | 6 | 484 |
| 55-64 years | 101 | 53 | – | 154 |
| ≥65 years | 35 | 34 | 2 | 71 |
| Unknown | 10 | 5 | 3 | 18 |
| Total | 1519 | 821 | 82 | 2422 |
The sentinel surveillance study of hepatitis testing, which began in 2002, aims to supplement routine surveillance of hepatitis A, B and C infections in England by providing information on trends in testing, individual risk exposures and clinical symptoms. The study collects information on hepatitis A, B and C testing carried out in participating centres regardless of test result and therefore can also be used to estimate prevalence in those individuals tested.
During the first quarter of 2009, a total of 38,144 individuals were tested at least once for hepatitis C-specific antibodies (anti-HCV) in 20 participating sentinel centres (table 6). This is the first time these individuals had been reported to the sentinel surveillance scheme. Dried blood spot testing has started in several areas and these data are currently included in the data presented. We are currently working to identify and split these samples and aim, in future reports, to show these data separately.
Overall, 3.6% of individuals tested for anti-HCV were positive, though this varied by region with the highest proportion of positive tests in the North West (table 6). This may reflect more targeted testing of risk groups and/or genuinely higher prevalence in people being tested in this region.
It is important to note that no laboratory methods are currently available to distinguish between acute or chronic hepatitis C virus infections. These positive anti-HCV results do not therefore necessarily represent incident infections.
Over recent months, dried blood spot testing [2] has started to be rolled out in several areas, including at some of the laboratories that participate in the sentinel surveillance study. We are currently working to collect these data and plan to present these data in future reports.
Table 6. Number of individuals tested, and testing positive, for anti-HCV in participating centres, January – March 2009*
| Region (number of centres) | Number tested | Number positive (%) |
| East Midlands (1) | 3,928 | 101 (2.6) |
| East of England (1) | 1,643 | 72 (4.4) |
| London (5) | 11,714 | 392 (3.3) |
| North East (1) | 465 | 24 (5.2) |
| North West (6) | 7,211 | 389 (5.4) |
| Northern Ireland † | 2 | 0 (0.0) |
| South Central (1) | 1,023 | 12 (1.2) |
| South East Coast (1) | 3,132 | 83 (2.7) |
| South West (1) | 3,775 | 141 (3.7) |
| Wales † | 13 | 1 (7.7) |
| West Midlands (1) | 1,376 | 33 (2.4) |
| Yorkshire and Humberside (2) | 3,862 | 139 (3.6) |
| Total, all regions (20) | 38,144 | 1,387 (3.6) |
Of the 1,387 individuals testing positive for anti-HCV during the first quarter of 2009, 895 (64.5%) were also tested for HCV RNA by PCR (qualitative and/or quantitative). Of these individuals, 608 were PCR positive (67.9%).
Gender was reported for the majority of people tested. As in previous quarters, similar numbers of males and females were tested (table 7); the ratio of males to females tested was 1.1:1. The ratio of males to females testing positive was 1.9:1. The largest group tested were aged 25-34 years (n=10,057). The percentage of individuals of known age testing positive was highest among 45-54 year olds (5.9%). The high level of individuals with unknown age testing positive (6.0%) may reflect testing of individuals in settings such as prisons, drug services and GUM clinics where few demographic details on patients were available and where service users may be at high risk of hepatitis C infection.
Table 7. Age and gender of individuals tested for anti-HCV in participating centres, January – March 2009*
| Age group | Female | Male | Unknown | Total |
| Number tested | Number positive (%) | Number tested | Number positive (%) | Number tested | Number positive (%) | Number tested | Number positive (%) |
| 1-14 | 287 | 3 (1.0) | 257 | 0 (0.0) | 8 | 0 (0.0) | 552 | 3 (0.5) |
| 15-24 | 3,791 | 49 (1.3) | 3,060 | 28 (0.9) | 74 | 0 (0.0) | 6,925 | 77 (1.1) |
| 25-34 | 4,630 | 159 (3.4) | 5,273 | 235 (4.5) | 154 | 7 (4.5) | 10,057 | 401 (4.0) |
| 35-44 | 3,589 | 133 (3.7) | 4,893 | 332 (6.8) | 113 | 8 (7.1) | 8,595 | 473 (5.5) |
| 45-54 | 1,905 | 66 (3.5) | 2,773 | 208 (7.5) | 52 | 7 (13.5) | 4,730 | 281 (5.9) |
| 55-64 | 1,469 | 27 (1.8) | 1,740 | 61 (3.5) | 24 | 0 (0.0) | 3,233 | 88 (2.7) |
| ≥65 years | 1,853 | 26 (1.4) | 2,052 | 28 (1.4) | 13 | 2 (15.4) | 3,918 | 56 (1.4) |
| Unknown | 29 | 2 (6.9) | 53 | 5 (9.4) | 52 | 1 (1.9) | 134 | 8 (6.0) |
| Total, all age groups | 17,553 | 465 (2.6) | 20,101 | 897 (4.5) | 490 | 25 (5.1) | 38,144 | 1,387 (3.6) |
To provide an indication of trends in testing, data from the 19 sentinel centres from which full data were available were compared for the first quarters of 2008 and 2009. In the period January to March 2009, 1,237 of 33,730 (3.7%) people tested were positive for anti-HCV, compared to 1,291 of 31,416 (4.1%) for the same period in 2008. This may suggest a greater proportion of people at lower risk of infection were tested during the first quarter of 2009, and/or the prevalence of hepatitis C is decreasing among the individuals tested.
References
1. HPA. Quarterly report from the sentinel surveillance study of hepatitis testing in England: data for October to December 2008 (quarter 4). Health Protection Report [serial online] 2009; 3(16): immunisation. Available at: http://www.hpa.org.uk/hpr/archives/2009/hpr1609.pdf
2. Judd A, Parry J, HickmanM, McDonald T, Jordan L, Lewis K, et al. Evaluation of a modified commercial assay in detecting antibody to hepatitis C virus in oral fluids and dried blood spots. J Med Virol 2003; 71(1) 49–55.
