Division Laboratory criteria

Laboratory test for case confirmation

At least one of the following four:

• Isolation of WNV from blood or CSF

• Detection of WNV nucleic acid in blood or CSF

• WNV specific antibody response (IgM) in CSF

• WNV IgM high titre AND detection of WNV IgG, AND confirmation by neutralisation

Laboratory test for a probable case

WNV specific antibody response in serum

Laboratory results need to be interpreted according to flavivirus vaccination status