Table 8.
Outbreak health data by water treatment type.
| Water Treatment Type | Median Case Count (n) | Median Attack Rate (n) |
|---|---|---|
| Untreated | 31 (704) | 25.6% (70) |
| Disinfection-Only | 94 (271) | 16.7% (74) |
| Disinfection-and-Filtration | 108 (117) | 28.2% (32) |
| Other Treatment 1 | 207 (72) | 5.1% (21) |
| Unknown Treatment | 53 (355) | 13.9% (17) |
1 Includes the water treatment types other undescribed treated, filtration-only, bankside filtration-and- chlorination, and reverse osmosis-only with 47, 21, three and one outbreak(s) recorded, respectively.