COVID-19 incubation period during a pandemic: a systematic review and meta-analysis
This review included 42 studies, mostly conducted in China. The mean and median incubation periods were up to 8 and 12 days, respectively. In various parametric models, the 95th percentile ranged from 10. 3 to 16 days. The highest 99th percentile was 20.4 days. Of the ten studies included in the meta-analysis, eight were conducted in China, one in Singapore, and one in Argentina. The pooled mean incubation period was 6.2 (95% CI 5.4, 7.0) days. Inclusion of study quality and the calculation method used as a moderator variable (I 2 0%) reduced the heterogeneity (I 2 77.1%; p <0.001). The mean incubation period ranged from 5.2 (95% CI 4.4 to 5.9) to 6. 65 days (95% CI 6.0 to 7.2).This study provides additional evidence of the incubation period of COVID-19 and shows that it is prudent not to dismiss the possibility of an incubation period of up to 14 days at this stage of the epidemic.
Dhouib, W., Maatoug, J., Ayouni, I. et al. The incubation period during the pandemic of COVID-19: a systematic review and meta-analysis. Syst Rev 10, 101 (2021). https://doi.org/10.1186/s13643-021-01648-y
Commentary
This study is a meta-analysis of 114 records screened from Medline and ScienceDirect database searches based on title and abstract, and 42 studies met the selection criteria and were reviewed. 42 studies, most of which were conducted in China, were included in the analysis. Most of the 42 studies were conducted in China, and the results showed that the mean incubation period was 8 days and the median was 12 days. Various parametric models showed a range of 10.3-16 days with a 95% confidence value, which did not seem to be in agreement with the initial WHO report.
Based on these results, a guideline of onset after 14 days of behavioral surveillance or quarantine has been stated, but some report that about 7.45% of patients were overestimated with an incubation period of more than 14 days. The limitations of this meta-analysis are recall bias and lack of generalizability in the evaluation, but I think it is a good result to know the incubation period.
