Estimation of Incubation Period and Serial Interval for SARS-CoV-2 in Jiangxi, China, and an Updated Meta-Analysis

Abstract

Introduction: This paper aims to estimate the incubation period and serial intervals for SARS-CoV-2 based on confirmed cases in Jiangxi Province of China and meta-analysis method.
 Methodology: Distributions of incubation period and serial interval of Jiangxi epidemic data were fitted by “fitdistrplus” package of R software, and the meta-analysis was conducted by “meta” package of R software.
 Results: Based on the epidemic data of Jiangxi, we found the median days of incubation period and serial interval were 5.9 days [IQR: 3.8 – 8.6] and 5.7 days [IQR: 3.6 – 8.3], respectively. The median days of the infectivity period at pre-symptomatic was 1.7 days [IQR: 1.1 – 2.4]. The meta-analysis based on 64 papers showed the pooled means of the incubation period and serial interval were 6.25 days (95% CrI: 5.75 – 6.75) and 5.15 days (95% CrI: 4.73 – 5.57), respectively.
 Conclusions: Our results contribute to a better understanding of COVID-19 and provide useful parameters for modelling the dynamics of disease transmission. The serial interval is shorter than the incubation period, which indicates that the patients are infectious at pre-symptomatic period, and isolation of detected cases alone is likely to be difficult to halt the spread of SARS-CoV-2.

Incubation Period of COVID-19 Caused by Unique SARS-CoV-2 Strains

“…One study used case data from multiple countries around the world, 81 6 studies were conducted in South Korea, 37 , 46 , 51 , 52 , 59 , 124 4 in France, 25 , 29 , 35 , 113 3 in Japan, 80 , 105 2 in Singapore, 87 , 111 2 in India, 16 , 78 , 83 , 103 2 in Vietnam, 21 , 58 and 2 in Australia. 45 , 99 One hundred nineteen studies (83.8%) included patients infected with the wild-type strain, 5 (3.5%) with the multiple strains, 17 , 26 , 35 , 80 , 112 and 11 (7.7%) with an unknown strain 84 , 93 , 99 , 106 , 116 , 126 , 135 , 142 , 148 , 150 , 157 (eTable 4 in the Supplement ).…”

The impact of school closure intervention during the third wave of the COVID-19 pandemic in Italy: Evidence from the Milan area

“…Moreover, it is reasonable to assume that the intervention would not exert its effects immediately at the cut-off; hence, we opted for a lagged impact model with slope change only [17]. Bearing in mind the average incubation period of the virus [19][20][21], we tested each model with a cut-off established at six days from the intervention date.…”

COVID‐19 in one region of New Zealand: a descriptive epidemiological study

“…We estimated an incubation period of 3.4 days, based on case interview data from established, exclusive pairs with well‐defined, short exposure periods in a low‐prevalence population. Results from 14 meta‐analyses suggest an incubation period of five to six days 9-22 . Most published incubation period estimates, the basis of the meta‐analyses, are derived from studies of one of two exposure types – exposure to Wuhan 23-28 or to a confirmed COVID‐19 case 29-38 .…”