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Background Patients receiving in-center hemodialysis treatment face unique challenges during the COVID-19 pandemic, specifically the need to attend for treatment that prevents self-isolation. Dialysis unit attributes and isolation strategies that might reduce dialysis center COVID-19 infection rates have not been previously examined. Methods We explored the role of variables including community disease burden, dialysis unit attributes (size, layout) and infection control strategies, on rates of COVID-19 among patients receiving in center hemodialysis in London, UK, between March 2nd 2020 and May 31st 2020. The two outcomes were defined as (i) a positive test for infection or admission with suspected COVID19 and (ii) admission to the hospital with suspected infection. Associations were examined using a discrete-time multi-level time-to-event analysis. Results Data on 5,755 patients, dialysing in 51 units were analysed. 990 (17%) tested positive and 465 (8%) were admitted with suspected COVID-19 between 2nd March and 31st May 2020. Outcomes were associated with age, diabetes, local community COVID-19 rates and dialysis unit size. Greater number of available side rooms and introduction of mask policies for asymptomatic patients were inversely associated with outcomes. No association was seen with sex, ethnicity, or deprivation indices nor with any of the different isolation strategies. Conclusions Rates of COVID-19 in the in center-hemodialysis population relate to individual factors, underlying community transmission, unit size and layout.

Background and objectivesPatients receiving hemodialysis are at high risk from coronavirus disease 2019 (COVID-19) and demonstrate impaired immune responses to vaccines. There have been several descriptions of their immunologic responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, but few studies have described the clinical efficacy of vaccination in patients on hemodialysis.Design, setting, participants, & measurementsIn a multicenter observational study of the London hemodialysis population undergoing surveillance PCR testing during the period of vaccine rollout with BNT162b2 and AZD1222, all of those positive for SARS-CoV-2 were identified. Clinical outcomes were analyzed according to predictor variables, including vaccination status, using a mixed effects logistic regression model. Risk of infection was analyzed in a subgroup of the base population using a Cox proportional hazards model with vaccination status as a time-varying covariate.ResultsSARS-CoV-2 infection was identified in 1323 patients of different ethnicities (Asian/other, 30%; Black, 38%; and White, 32%), including 1047 (79%) unvaccinated, 86 (7%) after first-dose vaccination, and 190 (14%) after second-dose vaccination. The majority of patients had a mild course; however, 515 (39%) were hospitalized, and 172 (13%) died. Older age, diabetes, and immune suppression were associated with greater illness severity. In regression models adjusted for age, comorbidity, and time period, prior two-dose vaccination was associated with a 75% (95% confidence interval, 56 to 86) lower risk of admission and 88% (95% confidence interval, 70 to 95) fewer deaths compared with unvaccinated patients. No loss of protection was seen in patients over 65 years or with increasing time since vaccination, and no difference was seen between vaccine types.ConclusionsThese data demonstrate a substantially lower risk of severe COVID-19 after vaccination in patients on dialysis who become infected with SARS-CoV-2.

Background Hemodialysis patients are at high risk from Covid-19, though vaccination has significant efficacy in preventing and reducing the severity of infection. Little information is available on disease severity and vaccine efficacy since dissemination of the Omicron variant. Methods In a multi-center study, during a period of the epidemic driven by the Omicron variant, all hemodialysis patients positive for SARS-CoV-2 were identified. Outcomes were analysed according to predictor variables including vaccination status. Risk of infection was analysed using a Cox proportional hazards model. Results SARS-CoV-2 infection was identified in 1126 patients including 200 (18%) unvaccinated, 56 (5%) post first dose, 433 (38%) post second dose, and 437 (39%) at least 7 days beyond their third dose. The majority of patients had a mild course but 160 (14%) were hospitalised and 28 (2%) died. In regression models adjusted for age and comorbidity, two-dose vaccination was associated with a 39% (95%CI: 2-62%) reduction in admissions, but third doses provided additional protection, with a 51% (95%CI: 25-69%) further reduction in admissions. Amongst 1265 patients at risk at the start of the observation period, SARS-CoV-2 infection was observed in 211 (17%). Two-dose vaccination was associated with a 41% (95%CI: 3-64%) reduction in the incidence of infection, with no clear additional effect provided by third doses. Conclusions These data demonstrate lower incidence of SARS-CoV-2 infection after vaccination in dialysis patients during an Omicron dominant period of the epidemic. Amongst those developing infection, severe illness was less common with prior vaccination, particularly after third vaccine doses.

Introduction There is paucity of literature comparing outcomes of kidney transplant patients with Covid-19 to that of dialysis and waitlisted patients. This report describes our data, provides comparative analysis, together with meta-analysis of published studies and describes our protocols to restart the transplant programme. Methods Data were analysed on kidney transplant, dialysis and waitlisted patients tested positive for SARS-CoV-2 (naso-pharyngeal swab PCR) between March 1, 2020 and June 30, 2020 together with meta-analysis of 16 studies. Results 23/1494 kidney transplant patients tested positive for SARS-CoV-2 compared to 123/1278 haemodialysis patients (1.5% vs 9.6%, p<0.001), 12/253 waitlisted patients (1.5% vs 4.7%, p=0.002). 19 required hospital admission, 6 died and 13 developed AKI. Overall case fatality ratio was 26.1% compared to patients on haemodialysis (27.6%, p=0.99) and waitlisted patients (8.3%, p=0.38). Within our entire cohort, 0.4% of transplant patients died compared to 0.4% of waitlisted patients and 2.7% of haemodialysis patients. Patients who died were older [Alive (median 71years) vs. Dead (median 59years), p=0.01]. In meta-analysis of 16 studies, including ours, pooled case fatality ratio was 24% [95%CI (19%, 28%)]; AKI proportion in 10 studies was 50% [95%CI (45%, 56%)], with some evidence against no heterogeneity between studies (p=0.02). Conclusions From our cohort of transplant patients, a significantly lower proportion of patients contracted COVID-19 compared to waitlisted and dialysis patients. The case fatality ratio was comparable to that of dialysis cohort and pooled case fatality ratio from meta-analysis of 16 studies. The pooled AKI ratio in the meta-analysis was similar to our experience.