SARS-CoV-2 monitoring at three sewersheds of different scales and complexity demonstrates distinctive relationships between wastewater measurements and COVID-19 case data.

Wastewater monitoring of SARS-CoV-2 presents a means of tracking COVID-19 community infection dynamics on a broader geographic scale. However, accounting for environmental and sample-processing losses may be necessary for wastewater measurements to readily inform our understanding of infection prevalence. Here, we present measurements of the SARS-CoV-2 N1 and N2 gene targets from weekly wastewater samples at three sites in Hamilton County, Ohio, during an increase and subsequent decline of COVID-19 infections. The concentration of N1 or N2 RNA in wastewater, measured over the course of six months, ranged from below the detection limit to over 104 gene copies/l, and correlated with case data at two wastewater treatment plants, but not at a sub-sewershed-level sampling site. We also evaluated the utility of a broader range of variables than has been reported consistently in previous work, in improving correlations of SARS-CoV-2 concentrations with case data. These include a spiked matrix recovery control (OC43), flow-normalization, and assessment of fecal loading using endogenous fecal markers (HF183, PMMoV, crAssphage). We found that adjusting for recovery, flow, and fecal indicators increased these correlations for samples from a larger sewershed (serving ~488,000 people) with greater industrial and stormwater inputs, but raw N1/N2 concentrations corresponded better with case data at a smaller, residential-oriented sewershed. Our results indicate that the optimal adjustment factors for correlating wastewater and clinical case data moving forward may not be generalizable to all sewersheds.

Where Did All the Appendicitis Go? Impact of the COVID-19 Pandemic on Volume, Management, and Outcomes of Acute Appendicitis in a Nationwide, Multicenter Analysis

Objective: The study objective was to evaluate effects of the COVID-19 pandemic on rates of emergency department (ED) acute appendicitis presentation, management strategies, and patient outcomes. Summary Background Data: Acute appendicitis is the most commonly performed emergency surgery in the United States and is unlikely to improve without medical or surgical intervention. Dramatic reductions in ED visits prompted concern that individuals with serious conditions, such as acute appendicitis, were deferring treatment for fear of contracting COVID-19. Methods: Patients from 146 hospitals with diagnosed appendicitis and arrival between March 2016 and May 2020 were selected. Electronic medical records data were retrospectively reviewed to retrieve patient data. Daily admissions were averaged from March 2016 through May 2019 and compared with March 2020. April-specific admissions were compared across the 5-year pre-COVID-19 period to April 2020 to identify differences in volume, demographics, disease severity, and outcomes. Results: Appendicitis patient admissions in 2020 decreased throughout March into April, with April experiencing the fewest admissions. April 2020 experienced a substantial decrease in patients who presented with appendicitis, dropping 25.4%, from an average of 2030 patients (2016-2019) to 1516 in 2020. An even greater decrease of 33.8% was observed in pediatric patients (age <18). Overall, 77% of the 146 hospitals experienced a reduction in appendicitis admissions. There were no differences between years in percent of patients treated nonoperatively (P = 0.493) incidence of shock (P = 0.95), mortality (P = 0.24), or need for postoperative procedures (P = 0.81). Conclusions: Acute appendicitis presentations decreased significantly during the COVID-19 pandemic, while overall management and patient outcomes did not differ from previous years. Further research is needed focusing on putative explanations for decreased hospital presentations unrelated to COVID-19 infection and possible implications for surgical management of uncomplicated acute appendicitis. Keywords: acute appendicitis, COVID-19, decreasing volumes, multicenter study. © 2021 BMJ Publishing Group. All rights reserved.