ObSurv is the surveillance system established in 1996 for all general outbreaks of Infectious
Intestinal Disease (IID) in Scotland.
For the purpose of ObSurv an outbreak is defined as an
incident in which two or more linked cases experience the same illness or when the observed
number of cases unaccountably exceeds the expected number.
The system seeks information
on general outbreaks, defined as outbreaks affecting members of more than one household or
residents of an institution. This system does not include outbreaks were infection is believed
to have been acquired overseas. Overseas outbreaks are reported separately