Covid-19 Vaccine Protection among Children and Adolescents in Qatar.

BACKGROUND: The BNT162b2 vaccine against coronavirus disease 2019 (Covid-19) has been authorized for use in children 5 to 11 years of age and adolescents 12 to 17 years of age but in different antigen doses. METHODS: We assessed the real-world effectiveness of the BNT162b2 vaccine against infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children and adolescents in Qatar. To compare the incidence of SARS-CoV-2 infection in the national cohort of vaccinated participants with the incidence in the national cohort of unvaccinated participants, we conducted three matched, retrospective, target-trial, cohort studies - one assessing data obtained from children 5 to 11 years of age after the B.1.1.529 (omicron) variant became prevalent and two assessing data from adolescents 12 to 17 years of age before the emergence of the omicron variant (pre-omicron study) and after the omicron variant became prevalent. Associations were estimated with the use of Cox proportional-hazards regression models. RESULTS: Among children, the overall effectiveness of the 10-µg primary vaccine series against infection with the omicron variant was 25.7% (95% confidence interval [CI], 10.0 to 38.6). Effectiveness was highest (49.6%; 95% CI, 28.5 to 64.5) right after receipt of the second dose but waned rapidly thereafter and was negligible after 3 months. Effectiveness was 46.3% (95% CI, 21.5 to 63.3) among children 5 to 7 years of age and 16.6% (95% CI, -4.2 to 33.2) among those 8 to 11 years of age. Among adolescents, the overall effectiveness of the 30-µg primary vaccine series against infection with the omicron variant was 30.6% (95% CI, 26.9 to 34.1), but many adolescents had been vaccinated months earlier. Effectiveness waned over time since receipt of the second dose. Effectiveness was 35.6% (95% CI, 31.2 to 39.6) among adolescents 12 to 14 years of age and 20.9% (95% CI, 13.8 to 27.4) among those 15 to 17 years of age. In the pre-omicron study, the overall effectiveness of the 30-µg primary vaccine series against SARS-CoV-2 infection among adolescents was 87.6% (95% CI, 84.0 to 90.4) and waned relatively slowly after receipt of the second dose. CONCLUSIONS: Vaccination in children was associated with modest, rapidly waning protection against omicron infection. Vaccination in adolescents was associated with stronger, more durable protection, perhaps because of the larger antigen dose. (Funded by Weill Cornell Medicine-Qatar and others.).

Effect of addition of statins to antiviral therapy in hepatitis C virus-infected persons: Results from ERCHIVES.

UNLABELLED: 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) have been variably noted to affect hepatitis C virus (HCV) treatment response, fibrosis progression, and hepatocellular carcinoma (HCC) incidence, with some having a more potent effect than others. We sought to determine the impact of adding statins to antiviral therapy upon sustained virological response (SVR) rates, fibrosis progression, and HCC development among HCV-infected persons using the Electronically Retrieved Cohort of HCV Infected Veterans (ERCHIVES), an established, longitudinal, national cohort of HCV-infected veterans. Within ERCHIVES, we identified those who received HCV treatment and a follow-up of >24 months after treatment completion. We excluded those with human immunodeficiency virus coinfection, hepatitis B surface antigen positivity, cirrhosis, and HCC at baseline. Our main outcomes were liver fibrosis progression measured by FIB-4 scores, SVR rates, and incident HCC (iHCC). Among 7,248 eligible subjects, 46% received statin therapy. Statin use was significantly associated with attaining SVR (39.2% vs. 33.3%; P < 0.01), decreased cirrhosis development (17.3% vs. 25.2%; P < 0.001), and decreased iHCC (1.2% vs. 2.6%; P < 0.01). Statins remained significantly associated with increased odds of SVR (odds ratio = 1.44; 95% confidence interval [CI] = 1.29, 1.61), but lower fibrosis progression rate, lower risk of progression to cirrhosis (hazard ratio [HR] = 0.56; 95% CI = -0.50, 0.63), and of incident HCC (HR = 0.51; 95% CI = 0.34, 0.76) after adjusting for other relevant clinical factors. CONCLUSIONS: Statin use was associated with improved virological response (VR) rates to antiviral therapy and decreased progression of liver fibrosis and incidence of HCC among a large cohort of HCV-positive Veterans. These data support the use of statins in patients with HCV.