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BackgroundSince the onset of the global COVID-19 pandemic in early 2020, numerous studies have been conducted worldwide to understand our immune response to the virus and to vaccination. This study investigates the humoral response elicited by SARS-CoV-2 infection and by vaccination in the poorly studied population of food and retail workers. These occupations were classified as essential by the Public Health Agency of Canada, potentially placing this population at greater risk of infection. Such a risk requires access to reliable and adaptable serological assays that can be rapidly deployed to guide public health strategies. Here we investigate the benefits and limitations of applying adaptable, decentralized tests for population-level immune surveillance in response to a pandemic, even before centralized testing is available.Methods and findingsThe 1.5-year study period spans from early 2021, when vaccination became available in this region, to mid-2022, following the emergence of the first Omicron variants. The cohort of 304 food and retail workers was recruited in the Québec City area. Participants attended five evenly spaced visits, providing blood samples as well as information on SARS-CoV-2 symptoms or risk factors, prior antigen or PCR test results and vaccination status, as well as work-related risk factors and protective measures. Parallel COVID-19 serological assays were performed using both a standardized chemiluminescent ELISA assay at the centralized platform operated in partnership with the Public Health Agency of Canada, and a semi-automated in-house colorimetric ELISA assay developed at our decentralized site. The YES/NO determination of SARS-CoV-2 vaccine seroconversion and/or infection events using the SARS-CoV-2 ancestral spike protein and nucleocapsid protein validated coherence of the centralized and decentralized assays. The flexibility of the decentralized assays allowed broadening the study to determine cross-reactivity of IgG directed against the spike protein of the SARS-CoV-2 Delta and Omicron VOCs, and IgM directed against the ancestral spike and nucleocapsid proteins. The nature of the data obtained in the decentralized assays allowed treatment with a recently developed mathematical transformation to obtain normal distribution, enabling ANOVA-Welsh statistical analysis. Although no significant differences were observed in humoral response as related to BMI, age, level of education, or chronic illnesses in this cohort of workers, statistically higher levels of vaccine-induced antibodies were observed for restaurant workers and hardware store workers in the early stages of the study, compared to workers in bars and grocery stores and in non-smokers versus smokers.ConclusionsThis work highlights the importance of developing adaptable, decentralized tests for population-level immune surveillance in response to a pandemic, even before centralized testing is available. To our knowledge, no other study has reported such an extensive longitudinal investigation during key periods of the COVID-19 pandemic in a cohort of food and retail workers to analyze two types of immunoglobulin, three epitopes and antigens to three VOC. This study will inform strategies and measures to be implemented in the event of a future pandemic.

IntroductionEarly in the COVID-19 pandemic, reagent availability was not uniform, and infrastructure had to be urgently adapted to undertake COVID-19 surveillance.MethodsBefore the validation of centralized testing, two enzyme-linked immunosorbent assays (ELISA) were established independently at two decentralized sites using different reagents and instrumentation. We compared the results of these assays to assess the longitudinal humoral response of SARS-CoV-2-positive (i.e., PCR-confirmed), non-hospitalized individuals with mild to moderate symptoms, who had contracted SARSCoV-2 prior to the appearance of variants of concern in Québec, Canada.ResultsThe two assays exhibited a high degree of concordance to identify seropositive individuals, thus validating the robustness of the methods. The results also confirmed that serum immunoglobulins persist ≥ 6 months post-infection among non-hospitalized adults and that the antibodies elicited by infection cross-reacted with the antigens from P.1 (Gamma) and B.1.617.2 (Delta) variants of concern.DiscussionTogether, these results demonstrate that immune surveillance assays can be rapidly and reliably established when centralized testing is not available or not yet validated, allowing for robust immune surveillance.

Abstract SARS-CoV-2 variants of concern (VOCs) have emerged worldwide, with implications on the spread of the pandemic. Characterizing the cross-reactivity of antibodies against these VOCs is necessary to understand the humoral response of non-hospitalized individuals previously infected with SARS-CoV-2, a population that remains understudied. Thirty-two SARS-CoV-2-positive (PCR-confirmed) and non-hospitalized Canadian adults were enrolled 14–21 days post-diagnosis in 2020, before the emergence of the B.1.351 (also known as Beta), B.1.617.2 (Delta) and P.1 (Gamma) VOCs. Sera were collected 4 and 16 weeks post-diagnosis. Antibody levels and pseudo-neutralization of the ectodomain of SARS-CoV-2 spike protein/human ACE-2 receptor interaction were analyzed with native, B.1.351, B.1.617.2 and P.1 variant spike proteins. Despite a lower response observed for the variant spike proteins, we report evidence of a sustained humoral response against native, B.1.351, B.1.617.2 and P.1 variant spike proteins among non-hospitalized Canadian adults. Furthermore, this response inhibited the interaction between the spike proteins from the different VOCs and ACE-2 receptor for ≥ 16 weeks post-diagnosis, except for individuals aged 18–49 years who showed no inhibition of the interaction between B.1.617.1 or B.1.617.2 spike and ACE-2. Interestingly, the affinity (KD) measured between the spike proteins (native, B.1.351, B.1.617.2 and P.1) and antibodies elicited in sera of infected and vaccinated (BNT162b2 and ChAdOx1 nCoV-19) individuals was invariant. Relative to sera from vaccine-naïve (and previously infected) individuals, sera from vaccinated individuals had higher antibody levels (as measured with label-free SPR) and more efficiently inhibited the spike–ACE-2 interactions, even among individuals aged 18–49 years, showing the effectiveness of vaccination.

Abstract Objectives To show that robot‐assisted laparoscopic cutaneous continent urinary diversion (RALCCUD) is feasible and safe; however, data on clinical outcomes in adults are lacking. Materials and methods We conducted a retrospective study of all adults who underwent RALCCUD between 2017 and 2022 at a single tertiary reference centre. Patient characteristics, clinical information and perioperative outcomes were recorded. All patients underwent pre‐ and postoperative urodynamic evaluations. Functional outcomes were evaluated at 3 months, then yearly. Continence was defined as no stomal or urethral leakage. Results Twelve patients, mostly women (n = 11), median (IQR) age 47.4 (19–57) years underwent RALCCUD (four Mitrofanoff, four Yang‐Monti and four Casale). The main indication for surgery was inability to perform intermittent self‐catheterization through the native urethra. Eleven patients (92%) had neurogenic lower urinary tract disease caused by spinal cord injury or spinal dysraphism. Median (IQR) operative time was 313 (285–367) min. Four patients (33%) underwent concomitant procedures: three supratrigonal cystectomy (SC) with augmentation cystoplasty (AC) and one artificial urinary sphincter (AUS). No conversions to an open approach were required. Median (IQR) follow‐up was 51 (40–61) months. One early postoperative complication occurred (Clavien grade III). The late postoperative complication rate was 17%, with three complications occurring in three patients. At the last follow‐up, all patients could self‐catheterize through the tube, and the stomal and urethral continence rate was 100%. Conclusion RALCCUD is feasible and safe in adults, with a high rate of stomal and urethral continence and a low complication rate.

Objective: We aimed to compare perioperative and oncologic outcomes for patients undergoing robotic-assisted radical cystectomy (RARC) with intracorporeal ileal conduit (IC) and neobladder (NB) urinary diversion. Methods: Patients undergoing RARC with intracorporeal urinary diversion between January 2017 and January 2022 at the Icahn School of Medicine at Mount Sinai, New York, NY, USA were indexed. Baseline demographics, clinical characteristics, perioperative, and oncologic outcomes were analyzed. Survival was estimated with Kaplan-Meier plots. Results: Of 261 patients (206 [78.9%] male), 190 (72.8%) received IC while 71 (27.2%) received NB diversion. Median age was greater in the IC group (71 [interquartile range, IQR 65–78] years vs. 64 [IQR 59–67] years, p

Background: For females undergoing cystectomy and urinary diversion, decreases in sexual and urinary functions can have a significant impact on quality of life. Pelvic organ–preserving (POP) radical cystectomy (RC) has been proposed as an approach to improve postoperative functional outcomes. Objective: To evaluate postoperative functional outcomes of a robotic approach for female POP RC with intracorporeal urinary diversion. Design, setting, and participants: This was a multicenter retrospective study evaluating sexual, urinary, and oncological outcomes for sexually active females undergoing POP robot-assisted RC for ≤T2 bladder cancer. Exclusion criteria included multifocal, trigonal, or locally advanced tumors. Surgical procedure: We describe a step-by-step technique for POP robot-assisted RC with intracorporeal urinary diversion. Measurements: The primary outcome of the study was evaluation of sexual and urinary functions following surgery. Oncological outcomes were evaluated as a secondary endpoint. Results and limitations: Our study included 23 females who underwent POP robot-assisted RC between 2008 and 2020 with intracorporeal neobladder (87%) or ileal conduit (13%) reconstruction. The median follow-up was 20 mo. A postoperative sexual function questionnaire was completed by 15 patients (65%). Of those, 13 (87%) resumed sexual activity at a median of 6 mo after surgery. Of the patients with a neobladder, 14 (70%) achieved daytime continence and 16 (80%) achieved nighttime continence. Cancer-specific and overall survival were both 91%. The results are limited by their retrospective nature. Conclusions: POP robot-assisted RC with orthotopic neobladder allows a majority of female patients to return to sexual activity after surgery. This approach should be considered for selected sexually active women. Patient summary: We evaluated 23 women with bladder cancer who underwent surgical removal of the bladder with preservation of their reproductive organs. Following this surgery, a majority of patients resumed sexual activity. For selected patients, this technique can be performed without compromising cancer control.