Table 1. Diagnostic criteria for surveillance of sporadic Creutzfeldt-Jakob disease from 1 January 2017.

1.1     DEFINITE:                     Progressive neurological syndrome AND                     Neuropathologically or immunohistochemically or biochemically confirmed

1.2     PROBABLE:                      1.2.1      I + two of II and typical electroencephalogram a            OR     1.2.2     I + two of II and typical magnetic resonance imaging brain scan b            OR     1.2.3     I + two of II and positive cerebrospinal fluid (CSF) 14-3-3            OR     1.2.4     Progressive neurological syndrome and positive real-time quaking-induced conversion in CSF or other tissues

1.3     POSSIBLE:                      I + two of II + duration <2 years

I         Rapidly progressive cognitive impairment

II       A    Myoclonus           B   Visual or cerebellar problems           C   Pyramidal or extrapyramidal features           D  Akinetic mutism

^aGeneralised periodic complexes. ^bHigh signal in caudate/putamen on magnetic resonance imaging brain scan or at least two cortical regions (temporal, parietal, occipital) on either diffusion-weighted imaging or fluid-attenuated inversion recovery.