Impact of Sample Storage Time and Temperature on the Stability of Respiratory Viruses and Enteric Viruses in Wastewater.

Wastewater-based surveillance (WBS) has been widely used to track SARS-CoV-2 as well as many other viruses in communities during the COVID pandemic and post-pandemic. However, it is still not clear how temperature and storage time would influence the stability of viruses in wastewater. In this study, we assessed the stability of SARS-CoV-2, pepper mild mottle virus (PMMoV), influenza viruses A (IAV) and B (IBV), respiratory syncytial virus (RSV), and enteric viruses in raw wastewater stored at room temperature, 4 °C, and -20 °C for 3 and 6 days.

Pediatric antibody responses to SARS-CoV-2 after infection and vaccination in Calgary, Canada.

Background: There are few reports of longitudinal serologic responses in children following Sars-CoV-2 infection and vaccination. This study describes longitudinal SARS-CoV-2 antibody responses following infection, vaccination, or both (hybrid immunity) in a cohort of Canadian children. The objectives of our study were to compare antibody levels following SARS-CoV-2 infection, vaccination, and hybrid immunity and to examine antibody decline after final antigen exposure.

Tracking SARS-CoV-2 Omicron lineages using real-time reverse transcriptase PCR assays and prospective comparison with genome sequencing.

Omicron has become the dominant SARS-CoV-2 variant globally since December 2021, with distinct waves being associated with separate Omicron sublineages. Rapid detection of BA.1, BA.

Multiplex Assays Enable Simultaneous Detection and Identification of SARS-CoV-2 Variants of Concern in Clinical and Wastewater Samples.

The targeted screening and sequencing approaches for COVID-19 surveillance need to be adjusted to fit the evolving surveillance objectives which necessarily change over time. We present the development of variant screening assays that can be applied to new targets in a timely manner and enable multiplexing of targets for efficient implementation in the laboratory. By targeting the HV69/70 deletion for Alpha, K417N for Beta, K417T for Gamma, and HV69/70 deletion plus K417N for sub-variants BA.

The evolution of SARS-CoV-2 seroprevalence in Canada: a time-series study, 2020-2023.

Background: During the first year of the COVID-19 pandemic, the proportion of reported cases of COVID-19 among Canadians was under 6%. Although high vaccine coverage was achieved in Canada by fall 2021, the Omicron variant caused unprecedented numbers of infections, overwhelming testing capacity and making it difficult to quantify the trajectory of population immunity.

Methods: Using a time-series approach and data from more than 900 000 samples collected by 7 research studies collaborating with the COVID-19 Immunity Task Force (CITF), we estimated trends in SARS-CoV-2 seroprevalence owing to infection and vaccination for the Canadian population over 3 intervals: prevaccination (March to November 2020), vaccine roll-out (December 2020 to November 2021), and the arrival of the Omicron variant (December 2021 to March 2023).

Wastewater surveillance monitoring of SARS-CoV-2 variants of concern and dynamics of transmission and community burden of COVID-19.

Wastewater-based surveillance is a valuable approach for monitoring COVID-19 at community level. Monitoring SARS-CoV-2 variants of concern (VOC) in wastewater has become increasingly relevant when clinical testing capacity and case-based surveillance are limited. In this study, we ascertained the turnover of six VOC in Alberta wastewater from May 2020 to May 2022.

Adverse Events and Serological Responses After SARS-CoV-2 Vaccination in Individuals With Inflammatory Bowel Disease.

Introduction: We determined adverse events after 4 doses of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccine in those with inflammatory bowel disease (IBD), associations between antibodies and injection site reactions (ISR), and risk of IBD flare.

Methods: Individuals with IBD were interviewed for adverse events to SARS-CoV-2 vaccine. Multivariable linear regression assessed the association between antibody titers and ISR.

A longitudinal seroepidemiology study to evaluate antibody response to SARS-CoV-2 virus infection and vaccination in children in Calgary, Canada from July 2020 to April 2022: Alberta COVID-19 Childhood Cohort (AB3C) Study.

Background: Measurement of SARS-CoV-2 antibody seropositivity is important to accurately understand exposure to infection and/or vaccination in specific populations. This study aimed to estimate the serologic response to SARS-CoV-2 virus infection and vaccination in children in Calgary, Alberta over a two-year period.

Methods: Children with or without prior SARS-CoV-2 infections, were enrolled in Calgary, Canada in 2020.

Retrospective testing for the presence of monkeypox virus in a high-risk population from February-June 2022 in Alberta, Canada.

Background: A multi-country outbreak of monkeypox virus (MPXV) infections was identified by the World Health Organization in May 2022. The western Canadian province of Alberta identified its first case of MPXV in a returning traveller on June 2, 2022. We undertook a retrospective testing exercise to evaluate whether MPXV may have been circulating in the province earlier.

Evaluation of the ID NOW among symptomatic individuals during the Omicron wave.

Starting in December, 2020, the ID NOW was implemented throughout the province of Alberta, Canada (population 4.4 million) in various settings. ID NOW's test performance with SARS-CoV-2 Omicron variant BA.

Wastewater-Based Surveillance Is an Effective Tool for Trending COVID-19 Prevalence in Communities: A Study of 10 Major Communities for 17 Months in Alberta.

The correlations between SARS-CoV-2 RNA levels in wastewater from 12 wastewater treatment plants and new COVID-19 cases in the corresponding sewersheds of 10 communities were studied over 17 months. The analysis from the longest continuous surveillance reported to date revealed that SARS-CoV-2 RNA levels correlated well with temporal changes of COVID-19 cases in each community. The strongest correlation was found during the third wave ( = 0.

Number of COVID-19 cases required in a population to detect SARS-CoV-2 RNA in wastewater in the province of Alberta, Canada: Sensitivity assessment.

With a unique and large size of testing results of 1,842 samples collected from 12 wastewater treatment plants (WWTP) for 14 months through from low to high prevalence of COVID-19, the sensitivity of RT-qPCR detection of SARS-CoV-2 RNA in wastewater that correspond to the communities was computed by using Probit analysis. This study determined the number of new COVID-19 cases per 100,000 population required to detect SARS-CoV-2 RNA in wastewater at defined probabilities and provided an evidence-based framework of wastewater-based epidemiology surveillance (WBE). Input data were positive and negative test results of SARS-CoV-2 RNA in wastewater samples and the corresponding new COVID-19 case rates per 100,000 population served by each WWTP.

Comparison of SARS-CoV-2 spike antibody quantitative titer reporting using the World Health Organization International Standard Units by four commercial assays.

The accurate measurement of serological response to SARS-CoV-2 vaccination is needed to correlate responses with effective protective immunity. The World Health Organization (WHO) has created an international standard to allow harmonization of immune response assessment to an arbitrary unit across different commercial assays; however, the accuracy of reporting of SARS-CoV-2 spike antibody titers in international standard units (BAU or IU/mL) from commercial assays is not well studied. Here, we report the performance comparison of four quantitative commercial assays testing for SARS-CoV-2 spike immunoglobins using the WHO's international standard.

Prospective population-level validation of the Abbott ID NOW severe acute respiratory syndrome coronavirus 2 device implemented in multiple settings for testing asymptomatic and symptomatic individuals.

Objective: Diagnostic evaluation of the ID NOW coronavirus disease 2019 (COVID-19) assay in various real-world settings among symptomatic and asymptomatic individuals.

Methods: Depending on the setting, the ID NOW testing was performed using oropharyngeal swabs (OPSs) taken from patients with symptoms suggestive of COVID-19, asymptomatic close contacts, or asymptomatic individuals as part of outbreak point prevalence screening. From January to April 2021, a select number of sites switched from using OPS to combined oropharyngeal and nasal swab (O + NS) for ID NOW testing.

Evolving strategy for an evolving virus: Development of real-time PCR assays for detecting all SARS-CoV-2 variants of concern.

In order to detect the SARS-CoV-2 variants of concern (VOCs), five real-time reverse transcriptase PCR (rRT-PCR) assays were designed to target the critical discriminatory mutations responsible for the following amino acid changes in the spike protein: two Δ69-70 + N501Y + E gene triplexes (one optimized for Alpha [B.1.1.

Seropositivity to SARS-CoV-2 in Alberta, Canada in a post-vaccination period (March 2021-July 2021).

Background: The COVID-19 pandemic has necessitated the need to rapidly make public health decisions. We systematically evaluated SARS-CoV-2 seropositivity to understand local COVID-19 epidemiology and support evidence-based public health decision making.

Methods: Residual blood samples were collected for SARS-CoV-2 receptor binding domain (RBD) IgG testing over a 1-5 day period monthly from 26 February 2021-9 July 2021 from six clinical laboratories across the province of Alberta, Canada.

One Swab Fits All: Performance of a Rapid, Antigen-Based SARS-CoV-2 Test Using a Nasal Swab, Nasopharyngeal Swab for Nasal Collection, and RT-PCR Confirmation from Residual Extraction Buffer.

Background: Point-of-care SARS-CoV-2 antigen tests have great potential to help combat the COVID-19 pandemic. In the performance of a rapid, antigen-based SARS-CoV-2 test (RAT), our study had 3 main objectives: to determine the accuracy of nasal swabs, the accuracy of using nasopharyngeal swabs for nasal collection (nasalNP), and the effectiveness of using residual extraction buffer for real-time reverse-transcriptase PCR (RT-PCR) confirmation of positive RAT (rPan).

Methods: Symptomatic adults recently diagnosed with COVID-19 in the community were recruited into the study.

Effect of not vortexing nasopharyngeal and throat swabs on SARS-CoV-2 nucleic acid detection: A pilot study.

The processing of swabs for respiratory virus detection involves vortexing while still in the viral transport medium (VTM). The effect of not vortexing swabs prior to analysis has not been studied extensively for SARS-CoV-2 detection, and presents an opportunity to improve pre-analytic laboratory workflow. We aimed to assess the impact of not vortexing nasopharyngeal/throat swabs submitted in VTM for SARS-CoV-2 testing.

Respiratory virus coinfections with severe acute respiratory coronavirus virus 2 (SARS-CoV-2) continue to be rare one year into the coronavirus disease 2019 (COVID-19) pandemic in Alberta, Canada (June 2020-May 2021).

To assess the burden of respiratory virus coinfections with severe acute respiratory coronavirus virus 2 (SARS-CoV-2), this study reviewed 4,818 specimens positive for SARS-CoV-2 and tested using respiratory virus multiplex testing. Coinfections with SARS-CoV-2 were uncommon (2.8%), with enterovirus or rhinovirus as the most prevalent target (88.

Characterization of Swine Influenza A(H1N2) Variant, Alberta, Canada, 2020.

Influenza strains circulating among swine populations can cause outbreaks in humans. In October 2020, we detected a variant influenza A subtype H1N2 of swine origin in a person in Alberta, Canada. We initiated a public health, veterinary, and laboratory investigation to identify the source of the infection and determine whether it had spread.

Validating and optimizing the method for molecular detection and quantification of SARS-CoV-2 in wastewater.

Wastewater surveillance of SARS-CoV-2 has become a promising tool to estimate population-level changes in community infections and the prevalence of COVID-19 disease. Although many studies have reported the detection and quantification of SARS-CoV-2 in wastewater, remarkable variation remains in the methodology. In this study, we validated a molecular testing method by concentrating viruses from wastewater using ultrafiltration and detecting SARS-CoV-2 using one-step RT-qPCR assay.