Title
A Flexible Smoother Adapted to Censored Data With Outliers and Its Application to SARS-CoV-2 Monitoring in Wastewater
Abstract
A sentinel network, Obepine, has been designed to monitor SARS-CoV-2 viral load in wastewaters arriving at wastewater treatment plants (WWTPs) in France as an indirect macro-epidemiological parameter. The sources of uncertainty in such a monitoring system are numerous, and the concentration measurements it provides are left-censored and contain outliers, which biases the results of usual smoothing methods. Hence, the need for an adapted pre-processing in order to evaluate the real daily amount of viruses arriving at each WWTP. We propose a method based on an auto-regressive model adapted to censored data with outliers. Inference and prediction are produced via a discretized smoother which makes it a very flexible tool. This method is both validated on simulations and real data from Obepine. The resulting smoothed signal shows a good correlation with other epidemiological indicators and is currently used by Obepine to provide an estimate of virus circulation over the watersheds corresponding to about 200 WWTPs.
Year
DOI
Venue
2022
10.3389/fams.2022.836349
FRONTIERS IN APPLIED MATHEMATICS AND STATISTICS
Keywords
DocType
Volume
measurement error, smoothing algorithm, outliers, censored data, SARS-CoV-2, autoregressive model
Journal
8
Citations 
PageRank 
References 
0
0.34
0
Authors
9