Table 1. Characteristics of Lyme disease cases by stage, Ontario: 2015–14.
| Disease stage | Early localized | Early disseminated | Late disseminated | All Lyme disease cases* | P value |
|---|---|---|---|---|---|
| Incidence | |||||
| Number of cases (%) | 415 (36.6) | 216 (19.1) | 475 (41.9) | 1230 (100) | n/a |
| Rate/100,000 | 0.32 | 0.17 | 0.36 | 0.94 | n/a |
| Regions (rate/100,000) | |||||
| Central East | 73 (0.19) | 40 (0.11) | 53 (0.14) | 192 (0.51) | n/a |
| Central West | 59 (0.24) | 39 (0.16) | 62 (0.25) | 169 (0.67) | n/a |
| Eastern | 182 (1.06) | 89 (0.52) | 251 (1.46) | 573 (3.33) | n/a |
| North East | 5 (0.09) | 0 (0.00) | 7 (0.12) | 13 (0.23) | n/a |
| North West | 2 (0.08) | 4 (0.17) | 7 (0.29) | 21 (0.88) | n/a |
| Southwest | 16 (0.10) | 13 (0.08) | 29 (0.18) | 67 (0.42) | n/a |
| Toronto | 78 (0.29) | 31 (0.12) | 66 (0.25) | 195 (0.73) | n/a |
| Demographic | |||||
| Age range (years) | 1–87 | 1–88 | 2–93 | 1–93 | n/a |
| Mean (SD) age (years) | 43.7 (21.7) | 43.8 (20.0) | 43.6 (19.4) | 43.7 (20.3) | 0.9904‡ |
| Median | 47.0 | 46.5 | 46.0 | 47.0 | |
| Sex (% male) | 52.7 | 46.3 | 50.5 | 50.2 | 0.3170# |
| Clinical measures† | |||||
| Hospitalization, n (%) | 33 (8.0) | 32 (14.8) | 52 (11.0) | 137 (11.1) | 0.0274# |
| Erythema migrans, n (%) | 362 (87.2) | 135 (62.5) | 292 (61.5) | 789 (69.6) | <0.0001# |
| Flu-like, n (%) | 236 (56.9) | 190 (88.0) | 421 (88.6) | 847 (74.8) | <0.0001# |
| Cardiac, n (%) | 0 (0%) | 22 (10.2) | 43 (9.1) | 65 (5.7) | <0.0001# |
| Neurologic, n (%) | 0 (0%) | 204 (94.4) | 259 (54.5) | 463 (40.9) | <0.0001# |
| Arthritic, n (%) | 0 (0%) | 0 (0%) | 475 (100) | 475 (41.9) | <0.0001# |
| Temporal measures ₤ | |||||
| Mean (SD) time to notification (days) | 43.9 (122.1) | 67.4 (147.8) | 120.5 (226.9) | 86.2 (207.7) | <0.0001‡ |
| ≤30 days (%) | 54.8 | 44.3 | 35.5 | 45.2 | <0.0001# |
| 1–3 months (%) | 34.7 | 42.5 | 40.0 | 38.0 | 0.1183# |
| >3 months (%) | 10.4 | 13.2 | 24.5 | 16.8 | <0.0001# |
| Onset May-Sept (%) | 87.3 | 88.2 | 81.2 | 84.9 | 0.0130# |
* Includes 124 cases for whom disease stage could not be determined due to symptoms that are missing or not related to LD.
† Clinical measures, except hospitalization, include only cases with ≥ 1 reported symptom (n = 1,133).
₤Temporal measures include only cases with a symptom onset date (n = 1,104).
‡ ANOVA test
# Chi-square test