Table 2.
Comparison of non-clusters and clusters sequences identified by phylogenetic clustering analysis and associated to epidemiological evidences.
| Non-clusters (n = 574) | Clusters (n = 162) | P-value | Small clusters (2 to 3 participants) (n = 96) | P-value | Large clusters (4 to 11 participants) (n = 66) | P-value | Epidemiological clusters (n = 69) | P-value | |
|---|---|---|---|---|---|---|---|---|---|
| Male, n (%) | 291 (51) | 64 (40) | 0.01 | 43 (46) | 0.32 | 21 (32) | 0.004 | 22 (32) | 0.003 |
| Age, median [IQR] | 53 [34 – 71] | 56 [36 – 75] | 0.18 | 54 [36 – 69] | 0.95 | 59 [37 – 83] | 0.02 | 54 [35 – 82] | 0.07 |
| Hospitalisation, n (%) | 344/454 (76) | 85/114 (75) | 0.80 | 50/70 (71) | 0.45 | 35/44 (80) | 0.71 | 27/40 (67) | 0.25 |
| Hospitalisation ICU, n (%) | 95/490 (19) | 31/142 (22) | 0.55 | 23/85 (27) | 0.11 | 8/57 (14) | 0.37 | 5/62 (8) | 0.03 |
| Death, n (%) | 84/441 (19) | 30/112 (27) | 0.08 | 17/67 (25) | 0.25 | 13/45 (29) | 0.12 | 15/40 (37) | 0.01 |
| HCWs n (%) | 150 (26) | 56 (35) | 0.03 | 31 (32) | 0.20 | 25 (38) | 0.04 | 34 (49) | < 0.0001 |
| 19A, n (%) | 11 (2) | 4 (2) | 0.001 | 4 (4) | 0.02 | 0 (0) | < 0.0001 | 0 (0) | 0.0007 |
| 20A, n (%) | 279 (49) | 68 (42) | 36 (38) | 32 (48) | 33 (48) | ||||
| 20B, n (%) | 39 (7) | 17 (10) | 4 (4) | 13 (20) | 15 (22) | ||||
| 20C, n (%) | 113 (20) | 54 (33) | 33 (34) | 21 (32) | 13 (19) | ||||
| 20D, n (%) | 5 (1) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | ||||
| 20A.EU2, n (%) | 92 (16) | 14 (9) | 14 (15) | 0 (0) | 8 (12) | ||||
| 20E.EU1, n (%) | 35 (6) | 5 (3) | 5 (5) | 0 (0) | 0 (0) | ||||
| Number of clusters | 57 | 45 | 12 | 17 | |||||
| Cluster size, median [IQR] | 2 [2, 3] | 2 [2–2] | 4.5 [4–5.75] | 3 [2–5] |
N number, IQR interquartile range, ICU intensive care unit, HCWs health care workers.
Statistical analyses were performed against “Non-clustering group” by Fisher’s exact test and Chi-squared test for qualitative data or Mann–Whitney U test for quantitative data.