Surveillance for SARS-CoV-2 and its variants in wastewater of tertiary care hospitals correlates with increasing case burden and outbreaks.

Wastewater-based SARS-CoV-2 surveillance enables unbiased and comprehensive monitoring of defined sewersheds. We performed real-time monitoring of hospital wastewater that differentiated Delta and Omicron variants within total SARS-CoV-2-RNA, enabling correlation to COVID-19 cases from three tertiary-care facilities with >2100 inpatient beds in Calgary, Canada. RNA was extracted from hospital wastewater between August/2021 and January/2022, and SARS-CoV-2 quantified using RT-qPCR. Assays targeting R203M and R203K/G204R established the proportional abundance of Delta and Omicron, respectively. Total and variant-specific SARS-CoV-2 in wastewater was compared to data for variant specific COVID-19 hospitalizations, hospital-acquired infections, and outbreaks. Ninety-six percent (188/196) of wastewater samples were SARS-CoV-2 positive. Total SARS-CoV-2 RNA levels in wastewater increased in tandem with total prevalent cases (Delta plus Omicron). Variant-specific assessments showed this increase to be mainly driven by Omicron. Hospital-acquired cases of COVID-19 were associated with large spikes in wastewater SARS-CoV-2 and levels were significantly increased during outbreaks relative to nonoutbreak periods for total SARS-CoV2, Delta and Omicron. SARS-CoV-2 in hospital wastewater was significantly higher during the Omicron-wave irrespective of outbreaks. Wastewater-based monitoring of SARS-CoV-2 and its variants represents a novel tool for passive COVID-19 infection surveillance, case identification, containment, and potentially to mitigate viral spread in hospitals.

Perspectives of Canadian Healthcare and Harm Reduction Workers on Mobile Overdose Response Services: A Qualitative Study.

BACKGROUND: Supervised consumption sites (SCS) are an evidence-based intervention proven effective for preventing drug overdose deaths. Obstacles to accessing SCS include stigma, limited hours of operation, concerns about policing, and limited geographic availability. Mobile overdose response services (MORS) are novel technologies that provide virtual supervised consumption to help reduce the risk of fatal overdoses, especially for those who use alone. MORS can take various forms, such as phone-based hotlines and mobile apps. The aim of this article is to assess the perceptions of MORS among healthcare and harm reduction staff to determine if they would be comfortable educating clients about these services. METHODS: Twenty-two healthcare and harm reduction staff were recruited from Canada using convenience, snowball, and purposive sampling techniques to complete semistructured interviews. Inductive thematic analysis informed by grounded theory was used to identify main themes and subthemes. RESULTS: Four themes were identified: (1) increasing MORS awareness among healthcare providers was seen as useful; (2) MORS might lessen the burden of drug overdoses on the healthcare system but could also increase ambulance callouts; (3) MORS would benefit from certain improvements such as providing harm reduction resources and other supports; and (4) MORS are viewed as supplements for harm reduction, but SCS were preferred. CONCLUSIONS: This research provides valuable perspectives from healthcare and harm reduction workers to understand their perception of MORS and identifies key areas of potential improvement. Practical initiatives to improve MORS implementation outcomes exist.

Electronic harm reduction interventions for drug overdose monitoring and prevention: A scoping review.

BACKGROUND: Novel strategies are required to address rising overdose deaths across the globe. We sought to identify the breadth and depth of the existing evidence around electronic harm reduction (e-harm reduction) interventions that aimed to reduce the harms associated with substance use. METHODS: We conducted a scoping review according to the PRISMA-ScR and PRISMA for Searching guidelines. A health sciences librarian systematically searched seven health databases from inception until January 20, 2023. Citation chaining and reference lists of included studies were searched to identify additional articles. Two reviewers independently screened, extracted and charted the data. Additionally, we conducted a gray literature search and environmental scan to supplement the findings. RESULTS: A total of 51 studies met the criteria for inclusion (30 peer-reviewed articles and 21 non-peer reviewed). Most peer-reviewed studies were conducted in Western countries (USA = 23, Canada = 3, Europe = 3, China = 1) and among adult samples (adult = 27, youth/adults =1, unspecified = 2). Study designs were predominantly quantitative (n = 24), with a minority using qualitative (n = 4) or mixed methods (n = 2). Most e-harm reduction interventions were harm reduction (n = 15), followed by education (n = 6), treatment (n = 2), and combined/other approaches (n = 7). Interventions utilized web-based/mobile applications (n = 15), telephone/telehealth (n = 10), and other technology (n = 5). CONCLUSIONS: While e-harm reduction technology is promising, further research is required to establish the efficacy and effectiveness of these novel interventions.

Campus node-based wastewater surveillance enables COVID-19 case localization and confirms lower SARS-CoV-2 burden relative to the surrounding community.

Wastewater-based surveillance (WBS) has been established as a powerful tool that can guide health policy at multiple levels of government. However, this approach has not been well assessed at more granular scales, including large work sites such as University campuses. Between August 2021 and April 2022, we explored the occurrence of SARS-CoV-2 RNA in wastewater using qPCR assays from multiple complimentary sewer catchments and residential buildings spanning the University of Calgary's campus and how this compared to levels from the municipal wastewater treatment plant servicing the campus. Real-time contact tracing data was used to evaluate an association between wastewater SARS-CoV-2 burden and clinically confirmed cases and to assess the potential of WBS as a tool for disease monitoring across worksites. Concentrations of wastewater SARS-CoV-2 N1 and N2 RNA varied significantly across six sampling sites - regardless of several normalization strategies - with certain catchments consistently demonstrating values 1-2 orders higher than the others. Relative to clinical cases identified in specific sewersheds, WBS provided one-week leading indicator. Additionally, our comprehensive monitoring strategy enabled an estimation of the total burden of SARS-CoV-2 for the campus per capita, which was significantly lower than the surrounding community (p≤0.001). Allele-specific qPCR assays confirmed that variants across campus were representative of the community at large, and at no time did emerging variants first debut on campus. This study demonstrates how WBS can be efficiently applied to locate hotspots of disease activity at a very granular scale, and predict disease burden across large, complex worksites.

Longitudinal SARS-CoV-2 RNA wastewater monitoring across a range of scales correlates with total and regional COVID-19 burden in a well-defined urban population.

Wastewater-based epidemiology (WBE) is an emerging surveillance tool that has been used to monitor the ongoing COVID-19 pandemic by tracking SARS-CoV-2 RNA shed into wastewater. WBE was performed to monitor the occurrence and spread of SARS-CoV-2 from three wastewater treatment plants (WWTP) and six neighborhoods in the city of Calgary, Canada (population 1.44 million). A total of 222 WWTP and 192 neighborhood samples were collected from June 2020 to May 2021, encompassing the end of the first-wave (June 2020), the second-wave (November end to December 2020) and the third-wave of the COVID-19 pandemic (mid-April to May 2021). Flow-weighted 24-hour composite samples were processed to extract RNA that was then analyzed for two SARS-CoV-2-specific regions of the nucleocapsid gene, N1 and N2, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Using this approach SARS-CoV-2 RNA was detected in 98.06% (406/414) of wastewater samples. SARS-CoV-2 RNA abundance was compared to clinically diagnosed COVID-19 cases organized by the three-digit postal code of affected individuals' primary residences, enabling correlation analysis at neighborhood, WWTP and city-wide scales. Strong correlations were observed between N1 & N2 gene signals in wastewater and new daily cases for WWTPs and neighborhoods. Similarly, when flow rates at Calgary's three WWTPs were used to normalize observed concentrations of SARS-CoV-2 RNA and combine them into a city-wide signal, this was strongly correlated with regionally diagnosed COVID-19 cases and clinical test percent positivity rate. Linked census data demonstrated disproportionate SARS-CoV-2 in wastewater from areas of the city with lower socioeconomic status and more racialized communities. WBE across a range of urban scales was demonstrated to be an effective mechanism of COVID-19 surveillance.