Sexually-transmitted hepatitis C virus reinfections among people living with HIV in Taiwan: the emerging role of genotype 6

Effectiveness and evolution of anti-SARS-CoV-2 spike protein titers after three doses of COVID-19 vaccination in people with HIV

BACKGROUND

Real-world vaccine effectiveness following the third dose of vaccination against SARS-CoV-2 remains less investigated among people with HIV (PWH).

METHODS

PWH receiving the third dose of BNT162b2 and mRNA-1273 (either 50- or 100-μg) were enrolled. Participants were followed for 180 days until the fourth dose of COVID-19 vaccination, SARS-CoV-2 infection, seroconversion of anti-nucleocapsid IgG, death, or loss to follow-up. Anti-spike IgG was determined every 1-3 months.

RESULTS

Of 1427 participants undergoing the third-dose COVID-19 vaccination, 632 (44.3%) received 100-μg mRNA-1273, 467 (32.8%) 50-μg mRNA-1273, and 328 (23.0%) BNT162b2 vaccine and the respective rate of SARS-CoV-2 infection or seroconversion of anti-nucleocapsid IgG was 246.1, 280.8 and 245.2 per 1000 person-months of follow-up (log-rank test, p = 0.28). Factors associated with achieving anti-S IgG titers >1047 BAU/mL included CD4 count <200 cells/mm3 (adjusted odds ratio [aOR], 0.11; 95% CI, 0.04-0.31), plasma HIV RNA >200 copies/mL (aOR, 0.27; 95% CI, 0.09-0.80), having achieved anti-spike IgG >141 BAU/mL within 3 months after primary vaccination (aOR, 3.69; 95% CI, 2.68-5.07), receiving BNT162b2 vaccine as the third dose (aOR, 0.20; 95% CI, 0.10-0.41; reference, 100-μg mRNA-1273), and having previously received two doses of mRNA vaccine in primary vaccination (aOR, 2.46; 95% CI, 1,75-3.45; reference, no exposure to mRNA vaccine).

CONCLUSIONS

PWH receiving different types of the third dose of COVID-19 vaccine showed similar vaccine effectiveness against SARS-CoV-2 infection. An additional dose with 100-μg mRNA-1273 could generate a higher antibody response than with 50-μg mRNA-1273 and BNT162b2 vaccine.

Determining reinfection rates by hepatitis C testing interval among key populations: A systematic review and meta-analysis

BACKGROUND & AIMS

Detecting hepatitis C virus (HCV) reinfection among key populations helps prevent ongoing transmission. This systematic review aims to determine the association between different testing intervals during post-SVR follow-up on the detection of HCV reinfection among highest risk populations.

METHODS

We searched electronic databases between January 2014 and February 2023 for studies that tested individuals at risk for HCV reinfection at discrete testing intervals and reported HCV reinfection incidence among key populations. Pooled estimates of reinfection incidence were calculated by population and testing frequency using random-effects meta-analysis.

RESULTS

Forty-one single-armed observational studies (9453 individuals) were included. Thirty-eight studies (8931 individuals) reported HCV reinfection incidence rate and were included in meta-analyses. The overall pooled estimate of HCV reinfection incidence rate was 4.13 per 100 per person-years (py) (95% confidence interval [CI]: 3.45-4.81). The pooled incidence estimate among people who inject drugs (PWID) was 2.84 per 100 py (95% CI: 2.19-3.50), among men who have sex with men (MSM) 7.37 per 100 py (95% CI: 5.09-9.65) and among people in custodial settings 7.23 per 100 py (95% CI: 2.13-16.59). The pooled incidence estimate for studies reporting a testing interval of ≤6 months (4.26 per 100 py; 95% CI: 2.86-5.65) was higher than studies reporting testing intervals >6 months (5.19 per 100 py; 95% CI: 3.92-6.46).

CONCLUSIONS

HCV reinfection incidence was highest in studies of MSM and did not appear to change with retesting interval. Shorter testing intervals are likely to identify more reinfections, help prevent onward transmission where treatment is available and enable progress towards global HCV elimination, but additional comparative studies are required.

HCV Microelimination for High-risk Special Populations

The World Health Organization has set tremendous goals to eliminate viral hepatitis by 2030. However, most countries are currently off the track for achieving these goals. Microelimination is a more effective and practical approach that breaks down national elimination targets into goals for smaller and more manageable key populations. These key populations share the characteristics of being highly prevalent for and vulnerable to hepatitis C virus (HCV) infection. Microelimination allows for identifying HCV-infected people and linking them to care more cost-effectively and efficiently. In this review, we discuss the current obstacles to and progress in HCV microelimination in special populations, including uremic patients undergoing hemodialysis, people who inject drugs, incarcerated people, people living in hyperendemic areas, men who have sex with men with or without human immunodeficiency virus (HIV) infection, transgender and gender-diverse populations, and sex workers. Scaling up testing and treatment uptake to achieve HCV microelimination may facilitate global HCV elimination by 2030.

Risky sexual practices and hepatitis C viremia among HIV-positive men who have sex with men in Taiwan

BACKGROUND

Understanding the risk behaviors associated with sexually-transmitted hepatitis C virus (HCV) infection among men who have sex with men (MSM) may inform the public health policies and interventions aiming to achieve HCV microelimination.

METHODS

HIV-positive MSM who had one of the following conditions were enrolled to undergo face-to-face questionnaire interviews to collect information on their sexual practices in the past 12 months: (1) elevation of aminotransferases in the past 6 months; (2) acquisition of sexually transmitted infections in the past 6 months; and (3) previous HCV infections. Plasma HCV RNA were tested at enrolment and every 3 months during follow-up. Baseline characteristics and risky behaviors were compared to identify factors associated with HCV viremia between HCV-viremic MSM and HCV-aviremic MSM in multivariate analysis.

RESULTS

Among 781 MSM with a median age of 36 years, 57 (7.3%) had HCV viremia and 724 (92.7%) no HCV viremia during follow-up. A high proportion (38.9%) of the participants reported having used recreational drugs in the past 12 months, with 34.4% of them having slamming, but only 4.8% reported having shared their injection equipment. In multivariate analysis, use of recreational drugs (adjusted odds ratio [aOR], 2.14; 95% CI, 1.16-3.96), having participated in group sex (aOR, 2.35; 95% CI 1.24-4.40) and having had condomless receptive anal intercourse (aOR, 1.97; 95% CI 1.07-3.62) were significantly associated with HCV viremia.

CONCLUSION

Among high-risk HIV-positive MSM, use of recreational drugs and risky sexual contacts were associated with HCV viremia, suggesting the mucosal contacts as the major route of HCV transmission.

Hepatitis C microelimination among people living with HIV in Taiwan

To reach the WHO target of hepatitis C virus (HCV) elimination by 2025, Taiwan started to implement free-of-charge direct-acting antiviral (DAA) treatment programme in 2017. Evaluating the progress of HCV microelimination among people living with HIV (PLWH) is a critical step to identify the barriers to HCV elimination. PLWH seeking care at a major hospital designated for HIV care in Taiwan between January 2011 and December 2021 were retrospectively included. For PLWH with HCV-seropositive or HCV seroconversion during the study period, serial HCV RNA testing was performed using archived samples to confirm the presence of HCV viremia and estimate the prevalence and incidence of HCV viremia. Overall, 4199 PLWH contributed to a total of 27,258.75 person-years of follow-up (PYFU). With the reimbursement of DAAs and improvement of access to treatments, the prevalence of HCV viremia has declined from its peak of 6.21% (95% CI, 5.39–7.12%) in 2018 to 2.09% (95% CI, 1.60–2.77%) in 2021 (decline by 66.4% [95% CI, 55.4–74.7%]); the incidence has declined from 25.94 per 1000 PYFU (95% CI, 20.44–32.47) in 2019 to 12.15% per 1000 PYFU (95% CI, 8.14–17.44) (decline by 53.2% [95% CI, 27.3–70.6%]). However, the proportion of HCV reinfections continued to increase and accounted for 82.8% of incident HCV infections in 2021. We observed significant declines of HCV viremia among PLWH with the expansion of the DAA treatment programme in Taiwan. Further improvement of the access to DAA retreatments is warranted to achieve the goal of HCV microelimination.

Performance of Hepatitis C Virus (HCV) Core Antigen Assay in the Diagnosis of Recently Acquired HCV Infection among High-Risk Populations

How the hepatitis C virus (HCV) core antigen (HCVcAg) assay performs in detecting recently acquired HCV infection among people living with HIV (PLWH) and HIV-negative men who have sex with men (MSM) is rarely assessed in the Asia-Pacific region. High-risk participants, including PLWH with sexually transmitted infections (STIs), HCV clearance by antivirals or spontaneously, or elevated aminotransferases, HIV-negative MSM with STIs or on HIV preexposure prophylaxis, and low-risk PLWH were enrolled. Blood samples were subjected to 3-stage pooled-plasma HCV RNA testing every 3 to 6 months until detection of HCV viremia or completion of the 1-year follow-up. The samples at enrollment and all of the archived samples preceding the detection of HCV RNA during follow-up were tested for HCVcAg. During June 2019 and February 2021, 1,639 blood samples from 744 high-risk and 727 low-risk PLWH and 86 HIV-negative participants were tested for both HCV RNA and HCVcAg. Of 62 samples positive for HCV RNA, 54 (87.1%) were positive for HCVcAg. Of 1,577 samples negative for HCV RNA, 1,568 (99.4%) were negative for HCVcAg. The mean HCV RNA load of the 8 individual samples positive for HCV RNA but negative for HCVcAg was 3.2 (range, 2.5 to 3.9) log10 IU/mL, and that of the remaining 54 samples with concordant results was 6.2 (range, 1.3 to 8.5) log10 IU/mL. The positive predictive value (PPV) and negative predictive value (NPV) of HCVcAg were 85.7% and 99.5%, respectively. In at-risk populations, HCVcAg has a high specificity and NPV but lower sensitivity and PPV, particularly in individuals with low HCV RNA loads. IMPORTANCE The HCV core antigen assay has a high specificity of 99.4% and negative predictive value of 99.5% but a lower sensitivity of 87.1% and positive predictive value of 85.7% in the diagnosis of recently acquired HCV infection in high-risk populations. Our findings are informative for many countries confronted with limited resources to timely identify acute HCV infections and provide effective direct-acting antivirals to halt onward transmission.