Table 2.
Distribution of transmission chains for COVID-19 cases in Tianjin and Chengdu.
| Central node | Chain size | Tianjin | Chengdu | ||
|---|---|---|---|---|---|
| Maximum length of chains | Number of chains | Maximum length of chains | Number of chains | ||
| Hubei Province | 1 | 1 | 13 | 1 | 29 |
| 2 | 2 | 4 | 0 | 0 | |
| 3 | 3 | 1 | 2 | 1 | |
| Tianjin high-speed train administration | 1 | 1 | 7 | – | – |
| 3 | 3 | 1 | – | – | |
| 4 | 3 | 1 | – | – | |
| Infections directly related to Hubei Province | 1 | 1 | 26 | 1 | 34 |
| 2 | 2 | 7 | 2 | 3 | |
| 3 | 3 | 4 | 0 | 0 | |
| 4 | 4 | 4 | 0 | 0 | |
| 5 | 3 | 2 | 0 | 0 | |
| 6 | 4 | 3 | 0 | 0 | |
| Unclear exposures except Hubei Province | 1 | – | – | 1 | 19 |
| 3 | – | – | 3 | 1 | |
| 4 | – | – | 2 | 1 | |
| Total | – | – | 73 | – | 88 |