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Volume 29, Number 2—February 2023
Research Letter

Epidemiology of SARS-CoV-2 Omicron BA.5 Infections, Macau, June–July 2022

Weijia Xiong, Liping Peng, Tim K. TsangComments to Author , and Benjamin J. Cowling
Author affiliations: University of Hong Kong, Hong Kong (W. Xiong, L. Peng, T.K. Tsang, B.J. Cowling); Laboratory of Data Discovery for Health Limited, Hong Kong (T.K. Tsang, B.J. Cowling)

Main Article


Estimated incubation periods for SARS-CoV-2 Omicron BA.5 variant according to population percentiles using lognormal, gamma, or Weibull probability distributions in study of epidemiology of SARS-CoV-2 Omicron BA.5 infections, Macau, June–July 2022*

Percentile Incubation, d (95% Cl)
Lognormal Gamma Weibull
Mean 3.27 (3.07–3.45) 3.00 (2.83–3.16) 3.26 (3.07–3.40)
2.5th 1.46 (1.17–1.74) 1.87 (1.74–2.00) 1.10 (0.93–1.25)
5th 1.64 (1.37–1.90) 2.02 (1.89–2.16) 1.38 (1.20–1.52)
50th 3.04 (2.87–3.18) 2.95 (2.79–3.12) 3.23 (3.03–3.38)
95th 5.67 (4.97–6.67) 4.13 (3.94–4.33) 5.24 (4.74–5.52)
97.5th 6.39 (5.49–7.77) 4.39 (4.19–4.59) 5.61 (5.05–5.94)
7.34 (6.16–9.29)
4.70 (4.49–4.91)
6.03 (5.40–6.44)
AIC value† 360.80 377.57 370.45

*Mean number of days was estimated after adjusting for exponential growth. AIC, Akaike information criterion. †AIC values were calculated to compare the fit of each model.

Main Article

Page created: December 16, 2022
Page updated: January 21, 2023
Page reviewed: January 21, 2023
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