Wastewater-based surveillance is emerging as an important tool for the COVID-19 pandemic trending. Current methods of wastewater collection, such as grab and auto-composite sampling, have drawbacks ...that impede effective surveillance, especially from small catchments with limited accessibility. Passive samplers, which are more cost-effective and require fewer resources to process, are promising candidates for monitoring wastewater for SARS-CoV-2. Here, we compared traditional auto sampling with passive sampling for SARS-CoV-2 detection in wastewater. A torpedo-style 3D-printed passive sampler device containing both cotton swabs and electronegative filter membranes was used. Between April and June 2021, fifteen passive samplers were placed at a local hospital's wastewater outflow alongside an autosampler. Reverse transcription and quantitative polymerase chain reaction (RT-qPCR) was used to detect SARS-CoV-2 in the samples after processing and RNA extraction. The swab and membrane of the passive sampler showed similar detection rates and cycle threshold (Ct) values for SARS-CoV-2 RNA for the N1 and N2 gene targets. The passive method performed as well as the grab/auto sampling, with no significant differences between N1 and N2 Ct values. There were discrepant results on two days with negative grab/auto samples and positive passive samples, which might be related to the longer duration of passive sampling in the study. Overall, the passive sampler was rapid, reliable, and cost-effective, and could be used as an alternative sampling method for the detection of SARS-CoV-2 in wastewater.
Supplemental O2 is not always available at health facilities in low-income and middle-income countries (LMICs). Solar-powered O2 delivery can overcome gaps in O2 access, generating O2 independent of ...grid electricity. We hypothesized that installation of solar-powered O2 systems on the paediatrics ward of rural Ugandan hospitals would lead to a reduction in mortality among hypoxaemic children.
In this pragmatic, country-wide, stepped-wedge, cluster randomised controlled trial, solar-powered O2 systems (ie, photovoltaic cells, battery bank, and O2 concentrator) were sequentially installed at 20 rural health facilities in Uganda. Sites were selected for inclusion based on the following criteria: District Hospital or Health Centre IV with paediatric inpatient services; supplemental O2 on the paediatric ward was not available or was unreliable; and adequate space to install solar panels, a battery bank, and electrical wiring. Allocation concealment was achieved for sites up to 2 weeks before installation, but the study was not masked overall. Children younger than 5 years admitted to hospital with hypoxaemia and respiratory signs were included. The primary outcome was mortality within 48 h of detection of hypoxaemia. The statistical analysis used a linear mixed effects logistic regression model accounting for cluster as random effect and calendar time as fixed effect. The trial is registered at ClinicalTrials.gov, NCT03851783.
Between June 28, 2019, and Nov 30, 2021, 2409 children were enrolled across 20 hospitals and, after exclusions, 2405 children were analysed. 964 children were enrolled before site randomisation and 1441 children were enrolled after site randomisation (intention to treat). There were 104 deaths, 91 of which occurred within 48 h of detection of hypoxaemia. The 48 h mortality was 49 (5·1%) of 964 children before randomisation and 42 (2·9%) of 1440 (one individual did not have vital status documented at 48 h) after randomisation (adjusted odds ratio 0·50, 95% CI 0·27–0·91, p=0·023). Results were sensitive to alternative parameterisations of the secular trend. There was a relative risk reduction of 48·7% (95% CI 8·5–71·5), and a number needed to treat with solar-powered O2 of 45 (95% CI 28–230) to save one life. Use of O2 increased from 484 (50·2%) of 964 children before randomisation to 1424 (98·8%) of 1441 children after randomisation (p<0·0001). Adverse events were similar before and after randomisation and were not considered to be related to the intervention. The estimated cost-effectiveness was US$25 (6–505) per disability-adjusted life-year saved.
This stepped-wedge, cluster randomised controlled trial shows the mortality benefit of improving O2 access with solar-powered O2. This study could serve as a model for scale-up of solar-powered O2 as one solution to O2 insecurity in LMICs.
Grand Challenges Canada and The Women and Children's Health Research Institute.
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. 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.
Skeletal muscle injury in Ebola virus disease (EVD) has been reported, but its association with morbidity and mortality remains poorly defined.
Retrospective study of patients admitted to two EVD ...Treatment Units, over an eight-month period in 2019, during a large EVD epidemic in the Democratic Republic of the Congo.
333 patients (median age 30 years, 58% female) had at least one creatine kinase (CK) measurement (total 2,229 CK measurements, median 5 (IQR 1-11) per patient). 271 patients (81%) had an elevated CK (>380U/L), 202 (61%) had rhabdomyolysis (CK>1,000 IU/L), and 45 (14%) had severe rhabdomyolysis (≥5,000U/L). Among survivors, the maximum CK level was median 1,600 (IQR 550 to 3,400), peaking 3.4 days after admission (IQR 2.3 to 5.5) and decreasing thereafter. Among fatal cases, the CK rose monotonically until death, with maximum CK level of median 2,900 U/L (IQR 1,500 to 4,900). Rhabdomyolysis at admission was an independent predictor of AKI (aOR 2.2 95%CI 1.2-3.8, p=0.0065) and mortality (aHR 1.7 95%CI 1.03-2.9, p=0.037).
Rhabdomyolysis is associated with AKI and mortality in EVD patients. These findings may inform clinical practice by identifying lab monitoring priorities and highlighting the importance of fluid management.
It has long been accepted that Shiga toxin (Stx) only exists in
serotype 1. However, in recent decades, the presence of Shiga toxin genes (
) in other
spp. have been reported. We screened 366
strains ...from Alberta, Canada (2003 to 2016) for
and 26 positive strains were identified. These isolates are highly related with the majority originating from the Dominican Republic and three isolates with Haiti origin. Both phylogenetic and spanning tree analysis of the 26 Alberta and 29
positive
originating from the U.S., France, Canada (Quebec) and Haiti suggests that there are geographic specific distribution patterns (Haiti and Dominican Republic clades). This study provides the first comprehensive whole genome based phylogenetic analysis of
positive
strains as well as their global transmission, which signify the public health risks of global spreading of these strains.
Although enteric multianalyte syndromic panels are increasingly employed, direct comparisons with traditional methods and the inclusion of host phenotype correlations are limited. Luminex xTAG ...gastrointestinal pathogen panel (GPP) and culture results are highly concordant. However, phenotypic and microbiological confirmatory testing raises concerns regarding the accuracy of the GPP, especially for
spp. A total of 3,089 children with gastroenteritis submitted stool specimens, rectal swab specimens, and clinical data. The primary outcome was bacterial pathogen detection agreement for shared targets between culture and the Luminex xTAG GPP. Secondary analyses included phenotype assessment, additional testing of GPP-negative/culture-positive isolate suspensions with the GPP, and in-house and commercial confirmatory nucleic acid testing of GPP-positive/culture-negative extracts. The overall percent agreement between technologies was >99% for each pathogen.
spp. were detected in specimens from 64 participants: 12 (19%) by culture only, 9 (14%) by GPP only, and 43 (67%) by both techniques. Positive percent agreement for
spp. was 78.2% (95% confidence interval CI, 64.6%, 87.8%). Isolate suspensions from the 12 participants with specimens GPP negative/culture positive for
tested positive by GPP. Specimens GPP positive/culture negative for
originated in younger children with less diarrhea and more vomiting. GPP-positive/culture-negative specimen extracts tested positive using additional assays for 0/2
-positive specimens, 0/4
O157-positive specimens, 0/9
-positive specimens, and 2/3
-positive specimens. For both rectal swab and stool samples, the median cycle threshold (
) values, determined using quantitative PCR, were higher for GPP-negative/culture-positive samples than for GPP-positive/culture-positive samples (for rectal swabs, 36.9 interquartile range {IQR}, 33.7, 37.1 versus 30.0 IQR, 26.2, 33.2, respectively
= 0.002; for stool samples, 36.9 IQR, 33.7, 37.1 versus 29.0 IQR, 24.8, 30.8, respectively
= 0.001). GPP and culture have excellent overall agreement; however, for specific pathogens, GPP is less sensitive than culture and, notably, identifies samples false positive for
spp.
Background. Nasopharyngeal (NP) specimens are commonly used for the detection of respiratory viruses, but throat and saliva specimens are easier to obtain. The objective of this study was to compare ...the viral yield of direct fluorescent antigen detection of NP specimens and nucleic acid amplification tests (NAT) of direct fluorescent antigen-negative NP specimens with the viral yield of NAT of throat swab and saliva specimens. Methods. NP, throat swab, and saliva specimens were obtained from children and adolescents aged ⩽17 years. Direct fluorescent antigen testing of the NP specimen for respiratory syncytial virus, influenza A and B viruses, and parainfluenza virus was performed. If no virus was detected, NAT was performed for these 4 viruses, adenovirus, and human metapneumovirus. If a virus was detected by either method, NAT for the same virus was performed for the corresponding throat swab and saliva specimens. Results. A virus was detected in 105 of the 137 NP specimens. The same virus was detectable by NAT in 87 (83%) of 105 throat swab specimens and 77 (74%) of 104 saliva specimens. The likelihood of viral detection among throat swab and saliva swab specimens was higher when the NP specimen tested positive by direct fluorescent antigen testing, compared with NAT alone, and when the specimens were obtained within 3 days after symptom onset, compared with later in the illness. Conclusions. Throat swab and saliva specimens are inferior to NP specimens for the detection of respiratory viruses but might be acceptable for screening in a setting where it is impractical to obtain an NP specimen.
Abstract
Background
Infections by previously underdiagnosed viruses astrovirus and sapovirus are poorly characterized compared with norovirus, the most common cause of acute gastroenteritis.
Methods
...Children <18 years old with acute gastroenteritis were recruited from pediatric emergency departments in Alberta, Canada between 2014 and 2018. We described and compared the clinical course of acute gastroenteritis in children with astrovirus, sapovirus, and norovirus.
Results
Astrovirus was detected in 56 of 2688 (2.1%) children, sapovirus was detected in 146 of 2688 (5.4%) children, and norovirus was detected in 486 of 2688 (18.1%) children. At illness onset, ~60% of astrovirus cases experienced both diarrhea and vomiting. Among sapovirus and norovirus cases, 35% experienced diarrhea at onset and 80% of 91% (sapovirus/norovirus) vomited; however, diarrhea became more prevalent than vomiting at approximately day 4 of illness. Over the full course of illness, diarrhea was 18% (95% confidence interval CI, 8%– 29%) more prevalent among children with astrovirus than norovirus infections and had longer duration with greater maximal events; there were a median of 4.0 fewer maximal vomiting events (95% CI, 2.0–5.0). Vomiting continued for a median of 24.8 hours longer (95% CI, 9.6–31.7) among children with sapovirus versus norovirus. Differences between these viruses were otherwise minimal.
Conclusions
Sapovirus infections attended in the emergency department are more similar to norovirus than previously reported, whereas astrovirus infections have several distinguishable characteristics.
Diarrhea was more prevalent, longer, and more intense in children with astrovirus-associated gastroenteritis than in children with norovirus infections; vomiting also persisted longer but was less intense. Sapovirus and norovirus infections were similar, differing only in sapovirus’ longer vomiting duration.
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.
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