Table 2.
Demographic characteristics of early COVID-19 cases compared with later cases in each affected country outside mainland China
| Early cases*in each country (n=874) | Later cases†in each country (n=326) | p value | ||
|---|---|---|---|---|
| Country income level‡ | ||||
| High income | 690 (79%) | 326 (100%) | <0·0001 | |
| Upper middle income | 129 (15%) | 0 | .. | |
| Lower middle income | 53 (6%) | 0 | .. | |
| Low income | 2 (<1%) | 0 | .. | |
| Age, years§ | 51 (35–63) | 55 (45–65) | <0·0001 | |
| <18 | 25/762 (3%) | 11/324 (4%) | <0·0001 | |
| 18–49 | 339/762 (44%) | 99/324 (31%) | .. | |
| ≥50 | 398/762 (52%) | 214/324 (66%) | .. | |
| Sex | .. | .. | 0·21 | |
| Male | 460/826 (56%) | 145/282 (51%) | .. | |
| Female | 366/826 (44%) | 137/282 (49%) | .. | |
| Special populations¶ | .. | .. | .. | |
| Health-care workers | 16 (2%) | 5 (2%) | 0·73 | |
| Pregnant women | 0 | 0 | .. | |
| Exposure history | .. | .. | .. | |
| Travel from affected countries | 375 (43%) | 17 (5%) | <0·0001 | |
| Contact with previously confirmed case | 244 (28%) | 27 (8%) | .. | |
| No travel history or contact with a previously confirmed case | 130 (15%) | 59 (18%) | .. | |
| Insufficient information | 125 (14%) | 223 (68%) | .. | |
| Deaths‖ | 48 (5%) | 4 (1%) | 0·0012 | |
Data are n or n/N (%) or median (IQR). p values are for the comparison between early and late cases. Analyses were restricted to cases with available data about patient age or sex and exclude cases associated with an outbreak among passengers on the Diamond Princess cruise ship in Yokohama Bay, Japan.
Defined as cases among the first 100 reported from each country and location.
Defined as cases reported after the first 100 in each country and location.
Defined based on World Bank gross national income per capita classification.9
Age data were available for 762 of 874 cases among the first 100 cases reported from countries and 324 of 326 cases among later cases reported from countries.
Health-care worker status and pregnancy status might have been underascertained because of under-reporting.
Deaths might have been underascertained because of incomplete follow-up reporting.