Table 1 Defining a health protection and a NCD “incident”

In the UK, a health protection incident may be defined as [12]:

- “an incident in which two or more people experiencing a similar illness are linked in time or place”

- “a greater than expected rate of infection compared with the usual background rate for the place and time where the incident has occurred”

- “a single case for certain rare diseases”

A NCD “incident” definition proposed by the authors as comprising:

- a significant and sustained step changed deterioration in population outcomes in comparison to the baseline trend or comparator

And

- the individuals or populations have similar conditions or have accessed the same health system and are linked in time or place

And there is

- potential for single cause or focus of variation