Purpose: Clinical significance and durability of serological response after mRNA COVID-19 vaccines is under investigation. Data on early virological response are limited. To identify potential predictors of antibody durability, circulating antibody levels were longitudinally explored in healthcare workers included in a follow-up program for SARS-CoV-2 infection. Methods: Subjects meeting the inclusion criteria signed an informed consent. Serum samples were collected at baseline, before the first BNT162b2 vaccine, at days 7, 21, 31, 90, and 180 days after the first dose. Serological evaluation was performed by QuantiVac Euroimmune anti-S1 antibody assay. Only subjects followed-up until day 90 are here considered. Results: Of 340 taken into consideration, 265 subjects were naive, and 75 COVID-19 experienced. The former showed a progressive increase in their antibody levels before day 90 decline, while the latter showed antibody levels reaching a plateau at day 7 and slightly declining at day 90. All showed antibody levels higher than the assay cut-off at day 31 and 90. Among naive, 108 had an early response whose predictors were younger age and female gender (OR 0.94, 95%CI 0.91–0.96, p < 0.0001; and OR 2.58, 95% CI 1.48–4.51, p = 0.0009). Naive subjects experienced a day 30/90 decline in antibody levels, whereas experienced did not. Early response was an independent predictor of higher day 30/90 antibody levels decline (OR = 2.05, 95% CI 1.04–4.02; p = 0.037). Conclusions: Our results suggest that in healthcare workers early response might be inversely associated with antibody levels 90 days after BNT162b2 vaccine.

Background Rates of Hepatitis C virus (HCV) testing and diagnosis are variable among people who use drugs (PWUD). In Puglia in 2018, of 871 subjects screened, 38% had HCV antibodies (HCVAb). Despite sustained virologic response at week 12 Sustained virologic response (SVR12) rates >95%, addiction centers in Italy are not allowed to prescribe direct‐acting antivirals (DAA). Aim To increase testing and linkage to care a dedicated program including “ad hoc” transportation and fast‐track access to care was offered to PWUD from Puglia. Methods Over 12 months, 1,470 individuals seen at 15 Services for Dependence (SERDs) underwent screening. For HCVAb positive, a fast‐track evaluation was offered at our Hepatology Unit. Patients were subsequently taken to their pharmacists to receive the prescribed DAA regimen. Treatment and adherence were supervised by SERDs physicians, SVR12 assessed at our unit. The scalability of the process was based on both, number of patients screened in our region in 2018, and number of PWUD diagnosed and treated at our center during 2018–2019. Results Of 1,470 individuals screened, 634 (43.1%) tested HCVAb positive. Overall, 231 were RNA positive, 54% of whom on opioid agonist therapy (OAT) and 32% with cirrhosis. Median interval between RNA assessment and treatment start was 22 days (0–300). Patients received 12‐week sofosbuvir/velpatasvir regimen without Ribavirin; in 220 patients who completed treatment, SVR12 was 98.6%. Among GT3, SVR12 was 98%. No re‐infection was observed. Improvements in screening, and linkage to care were registered. Conclusions A PWUD‐tailored service led to HCV care cascade improvement and high SVR12 rates. Despite history of drug addiction, social instability and logistic barriers, micro‐elimination programs providing dedicated care are key drivers of success.

Background: LC has been associated with hyporesponsiveness to several vaccines. Nonetheless, no data on complete serological and B- and T-cell immune response are currently available. Aims: To assess, in comparison with healthy controls of the same age and gender, both humoral and cellular immunoresponses of patients with LC after two or three doses of the mRNA Pfizer-BioNTech vaccine against SARS-CoV-2 and to investigate clinical features associated with non-response. Material and methods: 179 patients with LC of CTP class A in 93.3% and viral etiology in 70.1% of cases were longitudinally evaluated starting from the day before the first dose to 4 weeks after the booster dose. Their antibody responses were compared to those of healthcare workers without co-morbidities. In a subgroup of 40 patients, B- and T-cell responses were also compared to controls. Results: At d31, d90 and d180 after BNT162b2 vaccine, no detectable SARS-CoV-2 IgG response was observed in 5.9%, 3.9% and 7.2% of LC patients as compared to 0 controls (p < 0.03). A delay in B-cell and lack of prompt T-cell response compared to healthcare workers was also registered. A significant correlation between antibody titers and cellular response was observed. A MELD score > 8 was the only independent predictor of poor d31 response (p = 0.028). Conclusions: Our results suggest that cirrhotic patients have a slower and in <10% suboptimal immune response to SARS-CoV-2 vaccination. Rates of breakthrough infections were comparable between cirrhotics and controls. The booster dose was critical in inducing both humoral and cellular responses comparable to controls.