Norovirus case definition

Noroviral infection (Norovirus)

Clinical criteria

Any person with vomiting (particularly if projectile) AND/OR diarrhoea

Laboratory criteria
At least one of the following four:
- Detection of norovirus in faeces by electron microscopy
- Detection of virus-specific RNA in faeces
- Detection of virus-specific antigen in faeces
- Detection of small round structured virus in faeces by electron microscopy

Epidemiological criteria
One of the following epidemiological links:
- Human to human transmission
- Exposure to a common source

Case classification
A. Possible case
NA
B. Probable case
Any person meeting the clinical criteria and with an epidemiological link to a confirmed case
C. Confirmed case
Any person meeting the laboratory criteria 

Current as of: 22 January 2019