Table 7.5Health-based targets derived from example calculation in Table 7.4

Cryptosporidium Campylobacter Rotavirusa
Organisms per litre in raw water1010010
Health outcome target10−6 DALY per person per year10−6 DALY per person per year10−6 DALY per person per year
Risk of diarrhoeal illnessb1 per 1500 per year1 per 4600 per year1 per 14 000 per year
Drinking-water quality1 per 79 000 litres1 per 9500 litres1 per 90 000 litres
Performance targetc5.89 log10 units5.98 log10 units5.96 log10 units
a

Data from high-income regions. In low-income regions, severity is typically higher, but drinking-water transmission is unlikely to dominate.

b

For the susceptible population.

c

Performance target is a measure of log reduction of pathogens based on raw water quality.

From: 7, Microbial aspects

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Guidelines for drinking-water quality: Fourth edition incorporating the first and second addenda [Internet].
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