Volume 27, Number 2—February 2021
Effects of Social Distancing Measures during the First Epidemic Wave of Severe Acute Respiratory Syndrome Infection, 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, https://arxiv.org/abs/2003.09320) 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 (22–24)|
|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
|Length of infectiousness before symptoms, d (1/σs)||1.5||(22–24)|
|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|
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1These senior authors contributed equally to this article.
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