Prevalence of hepatitis B immunity and infection in home self-sampling HIV service users

Seroprevalence of immunity to hepatitis A and hepatitis B among gay, bisexual and other men who have sex with men (GBMSM) attending sexual health clinics in London and Leeds, England, 2017-2018

OBJECTIVES

Although hepatitis A virus (HAV) and hepatitis B virus (HBV) immunisation is recommended in the UK for gay, bisexual and other men who have sex with men (GBMSM), data on immunisation coverage are limited. We aimed to determine the seroprevalence of HAV and HBV immunity among a sample of GBMSM attending sexual health services (SHS) in England.

METHODS

Residual serum samples from HIV/syphilis testing for adult GBMSM attending eight SHS in London and one in Leeds were tested for markers of HAV immunity (HAV IgG) and HBV immunity (anti-HBs) using an unlinked anonymous approach. We estimated seroprevalence of HAV and HBV immunity overall and stratified by individuals' characteristics, which we obtained from the Genitourinary Medicine Clinic Activity Dataset Sexually Transmitted Infection (STI) Surveillance System. We used logistic regression to calculate crude and adjusted ORs between seropositivity and demographic and clinical characteristics.

RESULTS

Seroprevalence of immunity to HAV (74.5% of 2577) and HBV (77.1% of 2551) was high. In adjusted analysis, HAV IgG seroprevalence varied by clinic and WHO region of birth (global p<0.001 for each), increased with older age (ORs of 1.50 (95% CI 1.18 to 1.86), 2.91 (2.17 to 3.90) and 3.40 (2.44 to 4.75) for ages 26-35, 36-45 and >46 vs 18-25 years (global p<0.001), was higher in those with an STI in the past year (1.58 (1.25 to 2.00); p<0.001) and those who were living with HIV (1.82 (1.25 to 2.64); p<0.001). Anti-HBs seroprevalence varied by clinic (global p<0.001), increased with older age (global p<0.001) and was higher in those with an STI in the past year (1.61 (1.27 to 2.05); p<0.001).

CONCLUSION

Our findings provide a baseline seroprevalence from which to monitor serial levels of immunity to HBV and HAV in GBMSM accessing SHS. Levels of immunity for both viruses are high, noting samples were taken after recent widespread outbreaks and vaccination campaigns. High vaccine coverage in all GBMSM should be maintained to prevent further outbreaks.

Hepatitis B and hepatitis C testing outcomes among service users of Sexual Health London: an online sexually transmitted infection testing service for London residents

OBJECTIVES

The UK signed up to the 2016 global health strategy to eliminate viral hepatitis as a public health problem. Effective monitoring of hepatitis testing outcomes is required to track progress against targets. National reporting does not include hepatitis B and hepatitis C infections (HBV/HCV) detected by online sexually transmitted infection (STI) testing services (e-services). We identify HBV/HCV infection rates among individuals using Sexual Health London (SHL), a large e-service.

METHODS

SHL e-records of individuals receiving reactive HBsAg and/or HepCAb screening results between 1 January 2021 and 1 January 2022 were reviewed. Only at-risk groups are offered HBV/HCV testing, with risks captured via an online triage/consultation. Roche Cobas e801 HBV/HCV screening assay uses a cut-off index of reactivity (COI) to categorise results: low reactive (COI >1-9) and reactive (COI ≥10). SHL refers individuals with any reactive result for confirmatory testing (CT) at a sexual health clinic that provides hepatitis outpatient management. Clinic staff performing the CT access the shared SHL e-record and electronically take over the patient's care.

RESULTS

67, 718 HBV and 61 064 HCV tests were performed, representing 16% of all kit returns. HBV reactivity was 1.4% (922/67 718): 474 low-reactive, 302 reactive and 146 unconfirmed-reactive. HCV reactivity was 0.3% (163/61 064): 53 low-reactive, 99 reactive and 11 unconfirmed-reactive.Among individuals with reactive (COI ≥10) screening HBV results, 85% results confirmed, 12% negative and 3% unknown. For HCV, 79% results confirmed, 13% negative and 8% unknown. 57 out of 57 new HBV/HCV infections were electronically transferred. HBV prevalence was 299/67 718 (0.4%). The rate of previously undiagnosed cases detected was 40 out of 67 338 (0.06%) for HBV and 17 out of 61 016 (0.03%) for HCV.

CONCLUSIONS

16% of SHL service users received targeted testing for hepatitis in 2021. Testing volumes significantly exceeded and new HBV/HCV diagnosis rates were similar to those reported by sentinel laboratory surveillance. 100% new infections transitioned to care, demonstrating effective integration between online and local sexual health services.

Prevalence of anti-hepatitis B core in men who have sex with men attending a sexual health clinic in Brighton, UK, from 2012 to 2019

OBJECTIVE

Hepatitis B is sexually transmitted among men who have sex with men (MSM) and has previously been endemic in some populations of MSM. Presence of anti-hepatitis B core (anti-HBc) determines previous or ongoing infection. We aimed to establish the prevalence and associations of anti-HBc in our clinic population of MSM.

METHOD

A cross-sectional study of newly attending MSM to determine the prevalence and associations of testing positive for anti-HBc using our clinic database from 2012 to 2019. We used crude odds ratios to identify any associations.

RESULTS

There were 3342/5842 (58%) newly attending MSM who were tested for anti-HBc between 2012 and 2019. Of the 3342 MSM tested for anti-HBc, the median age was 30years (interquartile range 23-43), 442 (13%) were living with HIV, 10 (0.3%) were HBsAg positive, 62 (1.9%) had past/current hepatitis C, 401 (12%) had a positive syphilis enzyme immunoassay (EIA), 455 (14%) were diagnosed with either gonorrhoea or chlamydia and 1080 (32%) were non-UK born. A total of 331 (10%, 95% confidence interval (CI)=8.9-11.0) tested positive for anti-HBc and the proportion testing positive reduced significantly throughout the study period (P <0.004). Testing positive for anti-HBc was associated with age >30years (OR=8.2, 95% CI=5.9-11.4, P <0.0001), having past/current hepatitis C (odds ratio (OR)=5.0, 95% CI=3.0-8.6, P <0.0001), having a positive syphilis EIA (OR=5.9, 95% CI=4.4-7.3, P <0.0001) and being non-UK born (OR=1.4, 95% CI=1.1-1.8, P <0.006). There were no associations with HIV status or having a diagnosis of gonorrhoea or chlamydia.

CONCLUSION

Although reducing, the prevalence of anti-HBc remains endemic in MSM locally and further efforts are needed to enhance hepatitis B prevention strategies.