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Volume 27, Number 2—February 2021

Effects of Social Distancing Measures during the First Epidemic Wave of Severe Acute Respiratory Syndrome Infection, Greece

Vana SypsaComments to Author , Sotirios Roussos, Dimitrios Paraskevis, Theodore Lytras, Sotirios Tsiodras1, and Angelos Hatzakis1
Author affiliations: National and Kapodistrian University of Athens, Athens, Greece (V. Sypsa, S. Roussos, D. Paraskevis, S. Tsiodras, A. Hatzakis); National Public Health Organization, Athens (T. Lytras); European University Cyprus, Nicosia, Cyprus (T. Lytras)

Main Article

Table 1

Parameters of the susceptible-exposed-infectious-recovered model used to assess effects of social distancing measures during the first epidemic wave of coronavirus disease, Greece

Epidemiologic parameters Value Comments and references
R0 (95% CI) 2.38 (2.01–2.80) Estimated from data on the number of confirmed cases in Greece by accounting for imported cases and assuming gamma distributed serial interval with mean 6.67 days (SD 4.88 days) (D. Cereda et al., unpub. data, and aligned with other studies (10,11)
Latent period (1/σ) 3.5 days Based on an average incubation time of ≈5 days (8,9) and assuming that infectiousness starts 1.5 days prior to the symptom onset (2224)
Percentage (p) infected cases developing symptoms
From K. Mizumoto et al. (21), the estimated proportion of true asymptomatic cases was 20.6% assuming a mean incubation period of 5.5 days
Symptomatic cases
Length of infectiousness before symptoms, d (1/σs) 1.5 (2224)
Duration of infectious period from development of symptoms to recovery, d (1/γs)
To obtain a serial interval of ≈6 days (8,9)
True asymptomatic cases
Infectiousness (q) of asymptomatic vs. symptomatic persons, % 50 (24)
Duration of infectious period until recovery (1/γasymp) 6 days The same duration of infectiousness as for symptomatic cases = 1/σs + 1/γs

Main Article

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Main Article

1These senior authors contributed equally to this article.

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