Distribution of tuberculosis cases and molecular clusters in London (2010–2014), by cluster size
| Cases in cluster | Cases | Clusters |
| 1 (not clustered) | 3329 (44.6) | |
| 2 | 1044 (14.0) | 522 (52.4) |
| 3–20 | 2290 (30.7) | 454 (45.6) |
| >20 | 795 (10.7) | 20 (2.0) |
| Total | 7458 (100) | 996 (100) |
Data are presented as n (%).