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