Using automated extraction of hepatitis B tests for surveillance: evidence of decreasing incidence of acute hepatitis B in England.

Surveillance of acute hepatitis B in England is necessary to estimate incidence, determine routes of transmission and inform public health actions. Here we describe an automated process to extract information on testing for markers of hepatitis B infection in English sentinel laboratories between 2002 and 2008. The resulting data were used to identify individuals with acute infections, describe their characteristics and estimate the incidence of infection. Two-thirds of acute infections were in males. Heterosexual exposure and injecting drug use were the main risks reported. Annual incidence was estimated at 1.3/100 000 person-years overall (1.7 and 0.6 for males and females, respectively) and declined each year. Automated extraction of hepatitis B markers, including quantitative results where available, can help to classify HBV status more accurately for surveillance. HBV incidence in England is at its lowest level in recent years.

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

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 pound 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.

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.

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.