ABSTRACT
Background: Following the emergence of the Omicron B.1.1.529 variant of SARSCoV 2, Israel began on January 2, 2022, to administer a fourth dose of the BNT162b2 vaccine to people 60 years and older and to at-risk populations. Chronic dialysis patients were among the first to receive the fourth dose. Given the scarcity of evidence regarding the efficacy or necessity of a fourth dose.we assessed the clinical efficacy regarding infectivity and all-cause mortality of the fourth dose of the BNT162b2 vaccine among chronic dialysis patients. Method(s): This study was conducted using the electronic database of Clalit HMO in Israel. Chronic dialysis patients receiving hemodialysis and peritoneal dialysis during the COVID-19 pandemic were included. The control group was matched in a 4 to 1 ratio to the dialysis group. The study included the pre-vaccination and post-vaccination periods. Result(s): Included in this analysis were 14,230 patients of whom 2,846 were chronic dialysis patients with a mean age of 66.2+/-14.3 (range 18-97) years and 62.5% (1,779) were males. Mortality among unvaccinated chronic dialysis patients who tested positive for COVID-19 was 18.4%, as compared to 10.8% among similar patients who did not test positive for COVID-19 during the same period (OR 1.9, 95%CI 1.3-2.7;p=0.001). A total of 1,908 chronic dialysis patients had information available regarding vaccine status and were alive when vaccinations began in December 2020. Among them, 159 (8.3%) were unvaccinated, 113 (5.9%) were vaccinated with 1 dose, 270 (14.2%) with 2 doses, 703 (36.8%) with 3 doses, 663 (34.7%) with 4 doses. During 2022, which was dominated by the Omicron variant, 34.7% of chronic dialysis patients vaccinated with 3-doses were infected with SARS-CoV2 vs. 24.3% of 4-dose patients. Odds ratio for SARS-CoV2 infection after fourth dose was 0.6, (95%CI 0.5-0.8;p<0.001). Odds ratio for all-cause mortality in chronic dialysis patients who received 4 vs. 3 doses was 0.6 (0.4-0.9, 6.3% vs. 10.1%;p<0.001). Conclusion(s): As seen in the general population, and previous vaccine boosters, the fourth dose of the BNT162b2 vaccine reduced COVID-19 infections, as well as mortality among chronic dialysis patients. Additional studies are needed to establish the exact dose and schedule of the COVID-19 vaccine in patients treated with chronic maintenance dialysis.
ABSTRACT
BACKGROUND AND AIMS: COVID-19 is associated with increased morbidity and mortality in maintenance hemodialysis (MHD) patients. Recent breakthrough infection in vaccinated people has led some authorities to recommend a booster dose to patient fully vaccinated 5-8 months ago. The recent emergence of the Omicron (B.1.1.529) variant has heightened this issue. We aimed to assess, the humoral response following a booster dose with the BNT162b2 vaccine in MHD patients. METHOD: The study included 102 MHD patients vaccinated with 2 doses of the BNT162b2 (Pfizer-BioNTech) vaccine. A third dose (booster) was recommended to all MHD Patients in our center and was given to all patients that opt to receive it, resulting in a booster group and a control group that did not receive the booster. Previous exposure was excluded by testing for the presence of the Anti-Nucleocapsid Antibody (SARS-CoV-2) or positive PCR. We assessed the humoral response before and after the booster dose. RESULTS: 98.5% (65/66) subjects in the booster group developed a positive antibody response (472.7 ± 749.5 to 16 336.8 ± 15 397.3 AU/mL) as compared with a sustained decrease in the control group (n = 22, 695.7 ± 642.7 to 383.6 ± 298.6 AU/mL), P < 0.0001 (Figure 1). No significant adverse effects were reported. Prior antibody titers were positively correlated to IgG S1 levels following the booster dose. There was a significant association between malnutrition-inflammation markers and the humoral response. CONCLUSION: The vast majority of MHD patients developed a substantial humoral response following the booster dose administration, it was significantly higher than levels previously reported for MHD patients following administration of 2 doses alone. Further studies and observations are needed in order to determine the exact timing and dosing schedule.
ABSTRACT
TOPIC: Chest Infections TYPE: Original Investigations PURPOSE: The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to challenge the world. Even though effective vaccines have been developed, new variants of concern continue to emerge. While there is evidence of higher transmissibility rates of the B.1.1.7 variant and other variants, concerns regarding disease severity of these variants have not yet been confirmed. Patients undergoing maintenance hemodialysis are at increased risk for infection, with several reports of COVID-19 outbreaks in hemodialysis centers. The clinical outcomes of the SARS-CoV-2 variant viruses have not been reported or compared to non-variant SARS-CoV-2 among this unique population. The goal of the study was to compare the clinical outcomes and related mortality of infection with variant SARS-CoV-2 in chronic hemodialysis patients, and to compare it with infection by previous, non-variant strains of the virus. METHODS: This is a retrospective observational study comparing COVID-19 outbreaks of variant and non-variant SARS-CoV-2 strains in 2 hemodialysis centers in Israel. In one dialysis center ("center 1") an outbreak of COVID-19 caused by variant SARS-CoV-2 occurred starting from 28 December 2020. Subjects from a second hemodialysis center ("center 2") infected by non-variant SARS-CoV-2 in an earlier outbreak of COVID-19 which occurred from April 2020 to July 2020 served as control group. Complete SARS-CoV-2 genomes were sequenced via next generation sequencing (NGS).Primary outcome measures were 30-days mortality rates and in-hospital mortality rates. Secondary outcomes included mortality rates during follow-up, disease severity (according to NIH guidelines), need for respiratory support, type of respiratory support and need for hemodynamic support. RESULTS: Baseline subjects' characteristics were comparable. Chronic hemodialysis patients infected with SARS-CoV-2 variants had more severe infection and required more respiratory support, such as NIV (p=0.05), HFOT (p=0.021) and mechanical ventilation (p=0.05), as well as more hemodynamic support (p=0.05). Among patients from center 1, who were infected with virus variants, 71% were classified as critical vs. 8% of patients from center 2 (non-variant, p=0.005). 30-day mortality was higher among patients from center 1 as compared to center 2 (57.1% vs. 7.7.%, odds ratio for 30-day mortality in center 1 was 16, with 95% confidence interval 2-128, p=0.003).Multivariate analysis model for predictors of all-cause mortality showed that infection with a variant was the most important predictor of mortality. CONCLUSIONS: Infection with variant SARS-CoV-2 among chronic hemodialysis patients was strongly related with severe disease and mortality. CLINICAL IMPLICATIONS: SARS-CoV-2 genetic variation may affect clinical outcomes. Vaccination of hemodialysis patients should be prioritized. DISCLOSURES: No relevant relationships by sydney Benchetrit, source=Web Response No relevant relationships by keren cohen, source=Web Response No relevant relationships by Ayman Fadeela, source=Web Response No relevant relationships by Orna Mor, source=Web Response no disclosure on file for Naomi Nacasch;No relevant relationships by ori wand, source=Web Response no disclosure on file for Neta Zuckerman;