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 ...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-2RNA 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.The analyses determined that RT-qPCR-based SARS-CoV-2 RNA detection threshold at 50%,80%and 99%probability required a median of 8 (range:4-19),18 (9-43),and 38 (17-97) of new COVID-19 cases/100,000,respectively.Namely,the positive detection rate at 50%,80%and 99%probability were 0.01%,0.02%,and 0.04%averagely for new cases in the population.This study improves understanding of the performance of WBE SARS-CoV-2 RNA detection using the large datasets and prolonged study period.Estimated COVID-19 burden at a community level that would result in a positive detection of SARS-CoV-2 in wastewater is critical to support WBE application as a supplementary warning/monitoring system for COVID-19 prevention and control.展开更多
Wastewater surveillance(WS)of SARS-CoV-2 currently requires multiple steps and suffers low recoveries and poor sensitivity.Here,we report an improved analytical method with high sensitivity and recovery to quantify SA...Wastewater surveillance(WS)of SARS-CoV-2 currently requires multiple steps and suffers low recoveries and poor sensitivity.Here,we report an improved analytical method with high sensitivity and recovery to quantify SARS-CoV-2 RNA in wastewater.To improve the recovery,we concentrated SARS-CoV-2 viral particles and RNA from both the solid and aqueous phases of wastewater using an electronegative membrane(EM).The captured viral particles and RNA on the EM were incubated in our newly developed viral inactivation and RNA preservation(VIP)buffer.Subsequently,the RNA was concentrated on magnetic beads and inhibitors removed by washing.Without eluting,the RNA on the magnetic beads was directly detected using reverse transcription quantitative polymerase chain reaction(RT-qPCR).Analysis of SARS-CoV-2 pseudovirus(SARS-CoV-2 RNA in a noninfectious viral coat)spiked to wastewater samples showed an improved recovery of 80%.Analysis of 120 wastewater samples collected twice weekly between May 2021 and February 2022 from two wastewater treatment plants showed 100%positive detection,which agreed with the results independently obtained by a provincial public health laboratory.The concentrations of SARS-CoV-2 RNA in these wastewater samples ranged from 2.4×10^(2) to 2.9×10^(6) copies per 100 mL of wastewater.Our method’s capability of detecting trace and diverse concentrations of SARS-CoV-2 in complex wastewater samples is attributed to the enhanced recovery of SARS-CoV-2 RNA and efficient removal of PCR inhibitors.The improved method for the recovery and detection of viral RNA in wastewater is important for wastewater surveillance,complementing clinical diagnostic tests for public health protection.展开更多
Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications o...Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications of Raman imaging. By adsorbing Raman molecules onto specific nanostructures such as noble metals, Raman signals can be significantly enhanced, termed surfaceenhanced Raman scattering(SERS). Recent years have witnessed great interest in the development of SERS nanoprobes for Raman imaging. Rationally designed SERS nanoprobes have greatly enhanced Raman signals by several orders of magnitude, thus showing great potential for biomedical applications.In this review we elaborate on recent progress in design strategies with emphasis on material properties,modifying factors, and structural parameters.展开更多
Detection of SARS-CoV-2 RNA in wastewater is a promising tool for informing public health decisions during the COVID-19 pandemic.However,approaches for its analysis by use of reverse transcription quantitative polymer...Detection of SARS-CoV-2 RNA in wastewater is a promising tool for informing public health decisions during the COVID-19 pandemic.However,approaches for its analysis by use of reverse transcription quantitative polymerase chain reaction(RT-q PCR)are still far from standardized globally.To characterize inter-and intra-laboratory variability among results when using various methods deployed across Canada,aliquots from a real wastewater sample were spiked with surrogates of SARS-CoV-2(gamma-radiation inactivated SARS-CoV-2 and human coronavirus strain 229E[HCoV-229E])at low and high levels then provided"blind"to eight laboratories.Concentration estimates reported by individual laboratories were consistently within a 1.0-log_(10) range for aliquots of the same spiked condition.All laboratories distinguished between low-and high-spikes for both surrogates.As expected,greater variability was observed in the results amongst laboratories than within individual laboratories,but SARS-CoV-2 RNA concentration estimates for each spiked condition remained mostly within 1.0-log_(10) ranges.The no-spike wastewater aliquots provided yielded non-detects or trace levels(<20 gene copies/mL)of SARS-CoV-2 RNA.Detections appear linked to methods that included or focused on the solids fraction of the wastewater matrix and might represent in-situ SARS-CoV-2 to the wastewater sample.HCoV-229E RNA was not detected in the no-spike aliquots.Overall,all methods yielded comparable results at the conditions tested.Partitioning behavior of SARS-CoV-2 and spiked surrogates in wastewater should be considered to evaluate method effectiveness.A consistent method and laboratory to explore wastewater SARS-CoV-2 temporal trends for a given system,with appropriate quality control protocols and documented in adequate detail should succeed.展开更多
基金supported by research grants from the Canadian Institutes of Health Research [grant number VR5-172701, 2020]Alberta Innovates and Alberta Health [grant number RES0051047, 2020]。
文摘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-2RNA 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.The analyses determined that RT-qPCR-based SARS-CoV-2 RNA detection threshold at 50%,80%and 99%probability required a median of 8 (range:4-19),18 (9-43),and 38 (17-97) of new COVID-19 cases/100,000,respectively.Namely,the positive detection rate at 50%,80%and 99%probability were 0.01%,0.02%,and 0.04%averagely for new cases in the population.This study improves understanding of the performance of WBE SARS-CoV-2 RNA detection using the large datasets and prolonged study period.Estimated COVID-19 burden at a community level that would result in a positive detection of SARS-CoV-2 in wastewater is critical to support WBE application as a supplementary warning/monitoring system for COVID-19 prevention and control.
基金supported by the Natural Sciences and Engineering Research Council of Canada,the Canada Research Chairs Program,Alberta Innovates,and Alberta Health。
文摘Wastewater surveillance(WS)of SARS-CoV-2 currently requires multiple steps and suffers low recoveries and poor sensitivity.Here,we report an improved analytical method with high sensitivity and recovery to quantify SARS-CoV-2 RNA in wastewater.To improve the recovery,we concentrated SARS-CoV-2 viral particles and RNA from both the solid and aqueous phases of wastewater using an electronegative membrane(EM).The captured viral particles and RNA on the EM were incubated in our newly developed viral inactivation and RNA preservation(VIP)buffer.Subsequently,the RNA was concentrated on magnetic beads and inhibitors removed by washing.Without eluting,the RNA on the magnetic beads was directly detected using reverse transcription quantitative polymerase chain reaction(RT-qPCR).Analysis of SARS-CoV-2 pseudovirus(SARS-CoV-2 RNA in a noninfectious viral coat)spiked to wastewater samples showed an improved recovery of 80%.Analysis of 120 wastewater samples collected twice weekly between May 2021 and February 2022 from two wastewater treatment plants showed 100%positive detection,which agreed with the results independently obtained by a provincial public health laboratory.The concentrations of SARS-CoV-2 RNA in these wastewater samples ranged from 2.4×10^(2) to 2.9×10^(6) copies per 100 mL of wastewater.Our method’s capability of detecting trace and diverse concentrations of SARS-CoV-2 in complex wastewater samples is attributed to the enhanced recovery of SARS-CoV-2 RNA and efficient removal of PCR inhibitors.The improved method for the recovery and detection of viral RNA in wastewater is important for wastewater surveillance,complementing clinical diagnostic tests for public health protection.
基金the National Natural Science Foundation of China(Nos.81471779 and 31671003)Thousand Young Talents Program,the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(No.TP2014028)for their financial support
文摘Raman imaging yields high specificity and sensitivity when compared to other imaging modalities, mainly due to its fingerprint signature. However, intrinsic Raman signals are weak, thus limiting medical applications of Raman imaging. By adsorbing Raman molecules onto specific nanostructures such as noble metals, Raman signals can be significantly enhanced, termed surfaceenhanced Raman scattering(SERS). Recent years have witnessed great interest in the development of SERS nanoprobes for Raman imaging. Rationally designed SERS nanoprobes have greatly enhanced Raman signals by several orders of magnitude, thus showing great potential for biomedical applications.In this review we elaborate on recent progress in design strategies with emphasis on material properties,modifying factors, and structural parameters.
基金supported by a CHEO (Children’s Hospital of Eastern Ontario) CHAMO (Children’s Hospital Academic Medical Organization) grant, awarded to Dr.Alex E.Mac Kenziesupported by the “Next generation solutions to ensure healthy water resources for future generations” funded by the Global Water Futures program, Canada First Research Excellence Fund (#419205)+7 种基金supported by the Canada Research Chairs Program of the Natural Sciences and Engineering Research Council of Canada (NSERC)supported by funding from NSERC Discovery and Strategic Grant Programssupported by funding from an NSERC Discovery Grantsupported by the NSERC Alliance COVID-19 Grantby Mitacs through the Mitacs Accelerate programsupported by Canadian Institutes of Health Research (CIHR), Alberta Innovates, Alberta Health-Water for Life Strategysupported by the BC center for Disease Control, BC center for Disease Control Foundation for Public Health and Metro Vancouversupported by the Canada Research Chairs Program of NSERC。
文摘Detection of SARS-CoV-2 RNA in wastewater is a promising tool for informing public health decisions during the COVID-19 pandemic.However,approaches for its analysis by use of reverse transcription quantitative polymerase chain reaction(RT-q PCR)are still far from standardized globally.To characterize inter-and intra-laboratory variability among results when using various methods deployed across Canada,aliquots from a real wastewater sample were spiked with surrogates of SARS-CoV-2(gamma-radiation inactivated SARS-CoV-2 and human coronavirus strain 229E[HCoV-229E])at low and high levels then provided"blind"to eight laboratories.Concentration estimates reported by individual laboratories were consistently within a 1.0-log_(10) range for aliquots of the same spiked condition.All laboratories distinguished between low-and high-spikes for both surrogates.As expected,greater variability was observed in the results amongst laboratories than within individual laboratories,but SARS-CoV-2 RNA concentration estimates for each spiked condition remained mostly within 1.0-log_(10) ranges.The no-spike wastewater aliquots provided yielded non-detects or trace levels(<20 gene copies/mL)of SARS-CoV-2 RNA.Detections appear linked to methods that included or focused on the solids fraction of the wastewater matrix and might represent in-situ SARS-CoV-2 to the wastewater sample.HCoV-229E RNA was not detected in the no-spike aliquots.Overall,all methods yielded comparable results at the conditions tested.Partitioning behavior of SARS-CoV-2 and spiked surrogates in wastewater should be considered to evaluate method effectiveness.A consistent method and laboratory to explore wastewater SARS-CoV-2 temporal trends for a given system,with appropriate quality control protocols and documented in adequate detail should succeed.
