•One-step centrifugal ultrafiltration method to concentrate viruses from wastewater.•Comparable virus recovery and quantification to the commonly used VIRADEL method.•Virus infectivity was maintained ...during processing.•Rapid and effective approach to assess virus removal during wastewater treatment.
A one-step centrifugal ultrafiltration method was developed to enhance rapid detection of human enteric viruses and co-occurring viruses in wastewater. Samples were collected pre- and post-UV treatment at two full-scale tertiary municipal wastewater treatment plants in Calgary, Canada. Viruses were concentrated from 100mL wastewater samples through direct centrifugation using the Centricon Plus-70 ultrafilter. Seven viruses, including norovirus, rotavirus, sapovirus, astrovirus, enterovirus, adenovirus and JC virus, were tested using real-time quantitative PCR (rt-qPCR) and cell culture. All of the viruses were detected in pre- and post-UV samples by rt-qPCR, with rotavirus the most numerous (6.6 log10 GE copies/L). Infectious viruses, by cell culture, were found in all tested pre-UV samples but only in one post-UV sample. The results were comparable and consistent to that obtained using virus adsorption-elution method, indicating that the centrifugal ultrafiltration method is adequate to retain the viruses and maintain their infectivity during processing. As a simple, rapid and cost-effective method to screen wastewater viruses, this one-step centrifugal ultrafiltration method may serve as an effective approach to assess virus removal and gain knowledge of human virus activity during wastewater treatment.
Wastewater-based surveillance (WBS) of infectious diseases is a powerful tool for understanding community COVID-19 disease burden and informing public health policy. The potential of WBS for ...understanding COVID-19's impact in non-healthcare settings has not been explored to the same degree. Here we examined how SARS-CoV-2 measured from municipal wastewater treatment plants (WWTPs) correlates with workforce absenteeism. SARS-CoV-2 RNA N1 and N2 were quantified three times per week by RT-qPCR in samples collected at three WWTPs servicing Calgary and surrounding areas, Canada (1.4 million residents) between June 2020 and March 2022. Wastewater trends were compared to workforce absenteeism using data from the largest employer in the city (>15,000 staff). Absences were classified as being COVID-19-related, COVID-19-confirmed, and unrelated to COVID-19. Poisson regression was performed to generate a prediction model for COVID-19 absenteeism based on wastewater data. SARS-CoV-2 RNA was detected in 95.5 % (85/89) of weeks assessed. During this period 6592 COVID-19-related absences (1896 confirmed) and 4524 unrelated absences COVID-19 cases were recorded. A generalized linear regression using a Poisson distribution was performed to predict COVID-19-confirmed absences out of the total number of absent employees using wastewater data as a leading indicator (P < 0.0001). The Poisson regression with wastewater as a one-week leading signal has an Akaike information criterion (AIC) of 858, compared to a null model (excluding wastewater predictor) with an AIC of 1895. The likelihood-ratio test comparing the model with wastewater signal with the null model shows statistical significance (P < 0.0001). We also assessed the variation of predictions when the regression model was applied to new data, with the predicted values and corresponding confidence intervals closely tracking actual absenteeism data. Wastewater-based surveillance has the potential to be used by employers to anticipate workforce requirements and optimize human resource allocation in response to trackable respiratory illnesses like COVID-19.
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•WBS is a useful strategy for monitoring infectious diseases in workers.•SARS-CoV-2 RNA in wastewater correlated with workforce absenteeism.•Workplace absenteeism secondary to COVID-19 can be predicted using WBS.•WBS can be used by employers to anticipate and mitigate work force absenteeism.
Abstract
Background
Norovirus is a leading cause of acute gastroenteritis. With vaccines in development, population-based estimates of norovirus burden are needed to identify target populations, ...quantify potential benefits, and understand disease dynamics.
Methods
We estimated the attributable fraction (AF) for norovirus infections in children, defined as the proportion of children testing positive for norovirus whose gastroenteritis was attributable to norovirus. We calculated the standardized incidence and emergency department (ED) visit rates attributable to norovirus using provincial gastroenteritis visit administrative data.
Results
From 3731 gastroenteritis case patients and 2135 controls we determined that the AFs were 67.0% (95% confidence interval CI, 31.5%–100%) and 91.6% (88.8%–94.4%) for norovirus genogroups I (GI) and II (GII), respectively. Norovirus GII AF varied by season but not age. We attributed 116 episodes (95% CI, 103–129) and 59 (51–67) ED visits per 10 000 child-years to norovirus GII across all ages, accounting for 20% and 18% of all medically attended gastroenteritis episodes and ED visits, respectively.
Conclusions
In children, a large proportion of norovirus GII detections reflect causation, demonstrating significant potential for norovirus GII vaccines. Seasonal variation in the norovirus GII AF may have implications for understanding the role asymptomatic carriage plays in disease dynamics.
This study estimates the attributable fraction for norovirus infections in children and the corresponding attributable incidence and emergency department visit rates. In children, a large proportion of norovirus genogroup II detections reflect causation.
Asymptomatic SARS-CoV-2 infection in children is highly prevalent but its acute and chronic implications have been minimally described.
In this controlled case-ascertained household transmission ...study, we recruited asymptomatic children <18 years with SARS-CoV-2 nucleic acid testing performed at 12 tertiary care pediatric institutions in Canada and the United States. We attempted to recruit all test-positive children and 1 to 3 test-negative, site-matched controls. After 14 days' follow-up we assessed the clinical (ie, symptomatic) and combined (ie, test-positive, or symptomatic) secondary attack rates (SARs) among household contacts. Additionally, post-COVID-19 condition (PCC) was assessed in SARS-CoV-2-positive participating children after 90 days' follow-up.
A total of 111 test-positive and 256 SARS-CoV-2 test-negative asymptomatic children were enrolled between January 2021 and April 2022. After 14 days, excluding households with co-primary cases, the clinical SAR among household contacts of SARS-CoV-2-positive and -negative index children was 10.6% (19/179; 95% CI: 6.5%-16.1%) and 2.0% (13/663; 95% CI: 1.0%-3.3%), respectively (relative risk = 5.4; 95% CI: 2.7-10.7). In households with a SARS-CoV-2-positive index child, age <5 years, being pre-symptomatic (ie, developed symptoms after test), and testing positive during Omicron and Delta circulation periods (vs earlier) were associated with increased clinical and combined SARs among household contacts. Among 77 asymptomatic SARS-CoV-2-infected children with 90-day follow-up, 6 (7.8%; 95% CI: 2.9%-16.2%) reported PCC.
Asymptomatic SARS-CoV-2-infected children, especially those <5 years, are important contributors to household transmission, with 1 in 10 exposed household contacts developing symptomatic illness within 14 days. Asymptomatic SARS-CoV-2-infected children may develop PCC.
Aseptic meningitis Lee, Bonita E; Davies, H Dele
Current opinion in infectious diseases
20, Številka:
3
Journal Article
Recenzirano
To highlight some of the recent key epidemiologic and clinical diagnostic dilemmas of aseptic meningitis and to evaluate some tests that may help distinguish aseptic compared with bacterial ...meningitis.
Enteroviruses remain the most common cause of aseptic meningitis. Certain enteroviruses (e.g. coxsackie B5, echovirus 6, 9 and 30) are more likely to cause meningitis outbreaks, while others (coxsackie A9, B3 and B4) are mostly endemic. Nucleic acid tests are more sensitive than cultures in diagnosing enteroviral infections. In centers where the turnaround time for these tests is less than 24 h, there can be substantial cost savings and avoidance of unnecessary treatment of aseptic meningitis with antibiotics. Serum and stool specimens are important adjunct samples for diagnosing enteroviral infections in children. Cerebrospinal fluid protein (> or = 0.5 g/l) and serum procalcitonin (> or = 0.5 ng/ml) appear to be useful laboratory markers for distinguishing between bacterial and aseptic meningitis in children aged 28 days to 16 years, but they have relatively low sensitivity and specificity.
Enteroviruses are the major causes of aseptic meningitis. The major focus of diagnosis remains ruling out bacterial infection or confirming enteroviral etiology of infection. Properly implemented nucleic acid tests have the potential to reduce cost and unnecessary treatment.
Cerebrospinal fluid shunt–associated surgical site infection surveillance for 3 months compared to 12 months after surgery captures 83% of cases with no significant differences in patient ...characteristics, surgery types, or pathogens. A shorter 3-month follow-up can reduce resource use and allow for more timely reporting of healthcare-associated infection rates for hospitals.
Aim
To describe the epidemiology of critically ill children admitted to a paediatric intensive care unit (PICU) with acute respiratory disease. The association with intubation was analysed for the ...three most prevalent viruses and in those with and without viral co‐infection.
Methods
Patients admitted to the PICU (2004–2014) with acute respiratory disease were included. Analyses were performed utilising each respiratory viral infection or multiple viral infections as an exposure.
Results
There were 1766 admissions with acute respiratory disease of which 1372 had respiratory virus testing and 748 had one or more viruses detected. The risk of intubation before or during the PICU stay was higher if parainfluenza virus was detected compared to respiratory syncytial virus (RSV) (OR: 2.20; 95% CI: 1.06–4.56). Sixty‐three admissions had two or more viruses detected, and the combination of RSV and Rhinovirus/enterovirus was the most common. No significant difference was observed in the risk of intubation between patients with multiple and single viral infections.
Conclusion
Higher risk of intubation was found in patients with parainfluenza as compared to RSV. The risk of intubation comparing parainfluenza virus to other viruses and for patients with multiple versus single virus needs to be further studied.
Wastewater‐based surveillance has become an important tool for research groups and public health agencies investigating and monitoring the COVID‐19 pandemic and other public health emergencies ...including other pathogens and drug abuse. While there is an emerging body of evidence exploring the possibility of predicting COVID‐19 infections from wastewater signals, there remain significant challenges for statistical modeling. Longitudinal observations of viral copies in municipal wastewater can be influenced by noisy datasets and missing values with irregular and sparse samplings. We propose an integrative Bayesian framework to predict daily positive cases from weekly wastewater observations with missing values via functional data analysis techniques. In a unified procedure, the proposed analysis models severe acute respiratory syndrome coronavirus‐2 RNA wastewater signals as a realization of a smooth process with error and combines the smooth process with COVID‐19 cases to evaluate the prediction of positive cases. We demonstrate that the proposed framework can achieve these objectives with high predictive accuracies through simulated and observed real data.
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