Under investigation - A case which has been notified but information is not yet available to classify it as probable or confirmed.

Probable - A clinically compatible illness that is epidemiologically linked to a confirmed case.

Confirmed - A clinically compatible illness that is laboratory confirmed by a positive anti HAV IgM in serum.

Not a case - A case that has been investigated, and subsequently has been shown not to meet the case definition.

For more information refer to the Hepatitis A section of the Communicable Disease Control Manual.