Table 4.

Epidemiology of acute gastrointestinal illness ^a under the standard case definition

Incidence per person-year (95% CI)	1.16 (1.14–1.18)
Incidence per person-year in males	1.17
Incidence per person-year in females	1.14
Mean age of cases (years)	39.49
Mean duration of illness (days)	2.48
Cases with bloody diarrhoea (%)	0.96
Cases who sought medical care (%)	73.84
Cases submitting a stool sample for testing (%)	37.28
Cases with respiratory symptoms (%)	9.60
Cases with symptoms still ongoing at time of at interview (%)	8.65

CI, Confidence interval.

^aAcute gastrointestinal illness was defined as diarrhoea of ≥ 3 loose stools or any vomiting in a 24-hour period.