L. J. Brant

Hepatitis C prevalence in England remains low and varies by ethnicity: an updated evidence synthesis

BACKGROUND Previous evidence synthesis estimates of Hepatitis C Virus (HCV) in England did not consider excess HCV risk in ethnic minority populations. We incorporate new information on HCV risk among non-injectors by ethnic group, and additional information on injecting prevalence in order to generate new and updated estimates of HCV prevalence risk in England for 2005. METHODS Bayesian evidence synthesis was used to combine multiple sources of data that directly or indirectly provide information on the populations at risk, or prevalence of HCV infection. HCV data were modelled by region, age group and sex as well as ethnicity for never-injectors and by injecting status (ex and current). RESULTS Overall HCV antibody prevalence in England was estimated at 0.67% [95% credible interval (95% CrI): 0.50-0.94] of those aged 15-59 years, or 203 000 (153 000, 286 000) individuals. HCV prevalence in never-injectors remains low, even after accounting for ethnicity, with a prevalence of 0.05% (95% CrI 0.03-0.10) in those of white/other ethnicity and 0.76% (0.48-1.23) in South Asians. Estimates are similar to 2003, although patterns of injecting drug use are different, with an older population of current injecting drug users and lower estimated numbers of ex-injectors, but higher HCV prevalence. CONCLUSIONS Incorporating updated information, including data on ethnicity and improved data on injectors, gave similar overall estimates of HCV prevalence in England. Further information on HCV in South Asians and natural history of injecting are required to reduce uncertainty of estimates. This method may be applied to other countries and settings.

The burden of hepatitis C in England.

Summary.  In England, a large number of individuals are infected with the hepatitis C virus (HCV) and may develop future liver complications, such as decompensated cirrhosis and hepatocellular carcinoma (HCC). Estimates of the magnitude of this future burden are required to plan healthcare resources. We have estimated past incidence of HCV infection in England and predict future burden of end‐stage liver disease in the HCV‐infected population. A model of the natural history of HCV as a series of disease stages was constructed. A back‐calculation approach was performed, using the natural history model and data on annual HCC deaths in England from 1996 to 2004 with mention of HCV and hospital episode statistics for end‐stage liver disease with HCV. The number of HCV‐infected people living with compensated cirrhosis is predicted to rise from 3705 [95% credible interval (CrI): 2820–4975] in 2005 to 7550 (95% CrI: 5120–11 640) in 2015. The number of decompensated cirrhosis and/or HCC cases is also predicted to rise, to 2540 (95% CrI: 2035–3310) by 2015. HCV incidence increased during the 1980s, with an annual incidence of 12 650 (95% CrI: 6150–26 450) by 1989. HCV‐related cirrhosis and deaths from HCC in England are likely to increase dramatically within the next decade. If patients are left undiagnosed and untreated, the future burden of the disease on healthcare resources will be substantial.

Seroprevalence of low rubella IgG antibody levels among antenatal women in England tested by NHS Blood and Transplant: 2004–2009. Is rubella susceptibility increasing?

Antenatal testing for rubella susceptibility is undertaken to identify women at risk of exposure during pregnancy and to target post-partum immunisation. To evaluate the current rubella control programme and to inform future planning, data on anti-rubella IgG levels in antenatal sera tested by NHS Blood and Transplant were reviewed. The frequency of women with anti-rubella IgG <10 IU/mL increased by 60% over the 6-year study period and rates were significantly higher among younger women. The screening cut-off level of 10 IU/mL, used to identify women at risk, was determined in 1995 on the basis of early epidemiological studies and the correlates for protection now need review to support the appropriate management of a young immunised antenatal population. Ethnic minorities continue to be at increased risk of rubella susceptibility reinforcing the need to identify and opportunistically immunise these women.

Sentinel laboratory surveillance of hepatitis C antibody testing in England: understanding the epidemiology of HCV infection

This paper describes sentinel laboratory surveillance of hepatitis C antibody testing in England. Demographic and test result data were supplemented by follow-up questionnaires sent to the requesting clinician. Between October 2002 and September 2003 almost 75000 anti-HCV tests were performed in eight sentinel centres. More males were tested than females and over half of those tested were aged 25-44 years. Overall 5.7% (3333/58144, range 2.8-7.7%) individuals tested positive. Follow-up questionnaire data showed that 82% (1043/1277) of the positives had injecting drug use reported as the main risk exposure. The majority of negative individuals were undergoing routine screening as recommended for specific patient groups. Most individuals were asymptomatic. Antibody prevalence was estimated to be 34% in current injecting drug users and 42% in former injectors. Comparing positives to routine national surveillance suggests that only 53% (1782/3333) of diagnosed cases were reported. Sentinel laboratory data can provide valuable supplementary data to national surveillance.

Diagnosis of acute hepatitis C virus infection and estimated incidence in low‐ and high‐risk English populations

Summary.  The diagnosis of acute hepatitis C virus (HCV) infection is not straightforward; few people exhibit clinical symptoms and genome/antigen detection techniques do not indicate when infection had occurred. Here, a strategy to detect HCV RNA in the absence of antibody (‘window‐period’) for diagnosis of acute infection is assessed. The sentinel surveillance of hepatitis testing study was used to retrospectively identify anti‐HCV negative samples from high‐risk individuals (2002–2003), for testing singly for HCV RNA. Additional samples were identified prospectively (2005) and tested in pools for HCV RNA. Positive samples were genotyped. Incidence and costs of adopting the pooling strategy were estimated. In the retrospective study, 8/390 (2.1%) samples were confirmed HCV RNA positive, anti‐HCV negative. Prospectively, 3237 samples were tested in 325 pools. Five positive pools identified four confirmed HCV RNA positive patients (one false positive). Estimated incidence was 12.9 per 100 person‐years in injecting drug users (IDUs) (retrospective study) and 3.7 per 100 person‐years among drug/alcohol services and prison attendees (prospective study). Estimated costs were £850 per positive sample, in areas of higher risk. The yield from a window‐period strategy depends upon the population tested. Pooled HCV RNA testing of anti‐HCV negative samples from the current IDUs is realistic and relatively inexpensive to identify recently infected individuals.

Planning for the healthcare burden of hepatitis C infection: hepatitis C genotypes identified in England, 2002-2007.

BACKGROUND Identification of HCV genotype is a prerequisite for anti-viral treatment in England. Treatment length and sustained virological response rates vary by genotype. Therefore knowledge of circulating HCV genotypes is important for health-care providers. OBJECTIVES To describe the HCV genotypes identified in English laboratories and to investigate changes over time; sub-analysis of young adults (15-24 years) to provide information on recently circulating genotypes. STUDY DESIGN Data from the national reference laboratory and 19 English laboratories participating in the sentinel surveillance of hepatitis testing study were analysed. Multinomial regression was used to investigate trends in genotypes identified between 2002 and 2007. RESULTS HCV genotypes were available for 18,031 individuals. The majority (89%) of people were genotypes 1 and 3; 3a was the single largest subtype. Half of people born between 1960 and 1989 were genotype 3a and the majority of South Asian people were genotype 3a. People born pre-1940 were nine times more likely to have genotype 1b than 3a. The proportion of 1b infections, relative to 3a, declined over time, but, after adjusting for birth cohort, this effect disappeared. There was no evidence of a relative change in 1a infections. CONCLUSIONS This is the largest study of genotypes identified in England to date. Changes in genotypes over time were due to decreased genotyping of older individuals. As the population ages, the proportion of more difficult to treat genotypes may decline, leading to possible cost-savings for health-care providers, with a higher chance of achieving sustained virological response.

Hepatitis C and B testing in English prisons is low but increasing

BACKGROUND Prisons are important settings for blood-borne virus control because of the high prevalence of hepatitis C and B viral infections (HCV and HBV), and behaviours associated with transmission among prisoners. METHODS Data from sentinel laboratories in England were used to identify testing for hepatitis C (anti-HCV) and hepatitis B [hepatitis B surface antigen (HBsAg) and anti-hepatitis B core antigen (HBc)] among male and female prisoners between 2005 and 2008. RESULTS Between 2005 and 2008, 10 723 prisoners from 39 prisons in England were tested for anti-HCV, anti-HBc and/or HBsAg. Overall, 24.2% prisoners tested positive for anti-HCV. Anti-HCV testing increased 47% over 4 years (P < 0.001), whilst the proportion testing positive decreased significantly from 26% in 2005 to 23% in 2008 (χ(2)= 10.0, df = 3, P = 0.030). In total, 13.9% people tested positive for anti-HBc. Of 5151 people tested for anti-HBc, 4433 were also tested for HBsAg; of these 2.4% were HBsAg positive. HBsAg testing increased 35% between 2005 and 2008, with no significant change in the proportion testing positive. Between 2005 and 2008, 2.4% (CI: 2.32-2.43%) of the prison population (24 prisons) were estimated to have been tested for anti-HCV. CONCLUSIONS Although hepatitis testing has increased, only a small proportion of the prison population were tested. More testing is required to identify infected prisoners and refer them for appropriate treatment.

Where are people being tested for anti-HCV in England? Results from sentinel laboratory surveillance

Summary.  Many people infected with hepatitis C virus (HCV) are unaware of their infection and are, therefore. potentially infectious to others. To enable effective case‐finding policies to be developed, an understanding of where people, and injecting drug users (IDUs) in particular, are accessing HCV antibody testing is needed. HCV antibody testing data were collected electronically from 21 sentinel laboratories in England between 2002 and 2006 in this cross‐sectional study. Service types of the physician requesting the HCV test were identified and classified. Differences in people being tested in each service type and over time were investigated. Over half a million people were tested in 5 years. Whilst most testing took place in hospital, a large proportion of people were tested in community care, particularly in general practice surgeries and genito‐urinary medicine clinics. Younger people were more likely to be tested in community care, and there was evidence that testing differed according to ethnic status. IDUs were tested in all parts of the health services, although the highest proportion positive were from prisons and specialist services for drug users. Testing increased between 2002 and 2005 whilst the proportion of people testing positive declined. Routine laboratory data can provide valuable information on where people are being tested for HCV. Risk exposures should be investigated and testing targeted to people at higher risk for infection. Local laboratories should review data on testing locations and proportion positive to inform local initiatives to improve testing and yield.

Hepatitis C testing in sexual health services in England, 2002-7: Results from sentinel surveillance

Objectives To describe testing for hepatitis C virus (HCV) in sexual health services in England between 2002 and 2007, using data from a sentinel surveillance study of hepatitis testing. Methods Data on all anti-HCV tests carried out between 2002 and 2007 were collected from 20 participating laboratories. Test requests originating in sexual health services were identified, allowing analysis of the demographic and clinical characteristics of individuals tested in this setting. KC60 statutory returns data were used to estimate the proportion of new genitourinary medicine clinic attendees tested for hepatitis C each year. Results 90 424 individuals were tested for anti-HCV in 100 sexual health clinics; 3.2% (n=2858) were found to be positive. Multivariable analysis showed anti-HCV status to be associated with male sex and a reported history of injecting drug use. In those clinics for which data on trends were available, testing for anti-HCV increased over the study period and the percentage testing positive decreased. KC60 data suggested that most clinics tested less than 20% of new patients for anti-HCV, although the proportion of patients tested increased over time. Conclusions Sexual health services have become increasingly important locations for hepatitis C testing in England, although the proportion of patients testing positive is low compared with other settings. We suggest that testing in this setting could be better targeted to those most at risk of infection by thorough investigation of risk factors among service users.

Diagnoses of, and deaths from, severe liver disease due to hepatitis C in England between 2000 and 2005 estimated using multiple data sources.

Matching individuals reported to a sentinel surveillance scheme for hepatitis C between 2000 and 2005 to individuals with a hospital episode for hepatitis C-related liver disease in the same hospitals, we estimated that the number of cases of hepatitis C-related end-stage liver disease in these English hospitals was 42% (597/419) higher than Hospital Episode Statistics (HES) would indicate. Further, matching records of hepatitis C-related deaths in HES to death certificates, we estimated that, between 2000 and 2005, the true number of deaths from hepatitis C-related end-stage liver disease was between 185% (353/124) and 257% (378/106) higher than the number recorded in routine mortality statistics. We provide estimates of under-recording that can be used to modify existing models of disease burden due to hepatitis C and provide a simple approach to improve the monitoring of trends in severe hepatitis C-related morbidity over time.