Περίληψη:
During the COVID-19 pandemic, wastewater-based epidemiology (WBE) has
been engaged to complement medical surveillance and in some cases to
also act as an early diagnosis indicator of viral spreading in the
community. Most efforts worldwide by the scientific community and
commercial companies focus on the formulation of protocols for
SARS-CoV-2 analysis in wastewater and approaches addressing the
quantitative relationship between WBE and medical surveillance are
lacking. In the present study, a mathematical model is developed which
uses as input the number of daily positive medical tests together with
the highly non-linear shedding rate curve of individuals to estimate the
evolution of global virus shedding rate in wastewater along calendar
days. A comprehensive parametric study by the model using as input
actual medical surveillance and WBE data for the city of Thessaloniki
(similar to 700,000 inhabitants, North Greece) during the outbreak of
November 2020 reveals the conditions under which WBE can be used as an
early warning tool for predicting pandemic outbreaks. It is shown that
early warning capacity is different along the days of an outbreak and
depends strongly on the number of days apart between the day of maximum
shedding rate of infected individuals in their disease cycle and the day
of their medical testing. The present data indicate for Thessaloniki an
average early warning capacity of around 2 days. Moreover, the data
imply that there exists a proportion between unreported cases
(asymptomatic persons with mild symptoms that do not seek medical
advice) and reported cases. The proportion increases with the number of
reported cases. The early detection capacity of WBE improves
substantially in the presence of an increasing number of unreported
cases. For Thessaloniki at the peak of the pandemic in mid-November
2020, the number of unreported cases reached a maximum around 4 times
the number of reported cases. (C) 2021 The Authors. Published by
Elsevier B.V.
Συγγραφείς:
Petala, M.
Kostoglou, M.
Karapantsios, Th
Dovas, I, C. and
Lytras, Th
Paraskevis, D.
Roilides, E. and
Koutsolioutsou-Benaki, A.
Panagiotakopoulos, G.
Sypsa, V and
Metallidis, S.
Papa, A.
Stylianidis, E.
Papadopoulos, A. and
Tsiodras, S.
Papaioannou, N.
