Table 3.
Comparison of results from this study (year 2016) to comparable crude hospitalisation and death rates from other studies and surveillance data
| Exposure | Hospitalisation rate per 100 000 | Death rate per 100 000 | Source |
|---|---|---|---|
| Waterborne illness | NE | 0.56 | GBD 2015 estimate for unsafe water, sanitation and handwashing for Canada [5] |
| Foodborne illness | 50a | 0.51a | Drudge et al. [38] estimate for foodborne illness in Ontario |
| Waterborne illness | 39b | 2.3b | Table 6 of Adam et al. [22] for hospitalisations and Table 5 of Gargano et al. [16] for deaths, converted to crude rates |
| Waterborne illness | 12 | 0.52 | Present study |
| Unspecified GI illness | 13c | 0.23c | Thomas et al. [21] unspecified estimate for all transmission routes, multiplied by our waterborne transmission attributable fraction |
| Unspecified GI illness | 9.5c | 0.13c | Scallan et al. [20] unspecified estimate for all transmission routes, multiplied by our waterborne transmission attributable fraction |
| Unspecified GI illness | 7.51 | 0.21 | Present study |
| Pseudomonas spp. | 17b | 1.6b | Table 1 of Adam et al. [22] for hospitalisations and Table 5 of Gargano et al. [16] for deaths, converted to crude rates |
| Pseudomonas spp. | 1.3 | 0.05 | Present study |
| NTM | 4.0b | 0.41b | Table 1 of Adam et al. [22] for hospitalisations and Table 5 of Gargano et al. [16] for deaths, converted to crude rates |
| NTM | 1.4 | 0.22 | Present study |
| Legionella spp. | 0.82d | 0.07d | OAHPP (2019) reflecting 2016 provincial surveillance data |
| Legionella spp. | 0.97b | 0.08b | Table 1 of Adam et al. [22] for hospitalisations and Table 5 of Gargano et al. [16] for deaths, converted to crude rates |
| Legionella spp. | 0.66 | 0.04 | Present study |
GI, gastrointestinal; NTM, non-tuberculous mycobacteria; NE, not estimated.
This estimate for foodborne illness can be used to compare the foodborne and waterborne transmission routes for Ontario.
These estimates are not specific to waterborne transmission. The crude rates were calculated using a population estimate for the USA of 316.2 million (year 2013) for Adam et al. [22] and of 298.4 million (year 2006) for Gargano et al. [16]. Table 1 of Adam et al. [22] reported a hospitalisation total for 13 pathogens that converts to 32 per million and is used as the total when examining the contribution of specific pathogens.
We obtained or back-calculated the unspecified estimates for all transmission routes and reflecting both domestic and travel-acquired illness. We then multiplied the all transmission route estimate from the studies by our unspecified GI illness attributable fraction (mean of 0.102) for waterborne transmission.
These estimates are not specific to waterborne transmission. They reflect confirmed and probable cases reported to public health authorities in 2016. Hospitalisations reflect admissions up to 60 days before or 90 days after the episode. Deaths reflect any cause of death, unless there was an indication that the reportable disease was unrelated to the cause of death.