"The CNDSS collects, validates and maintains basic surveillance data on approximately 60 nationally notifiable diseases, dating back to 1924. Nationally notifiable diseases are infectious diseases that have been identified by the federal government and provinces and territories as priorities for monitoring and control efforts.
Provinces and territories voluntarily submit annual notifiable disease data, which are used to produce national disease counts and rates. Age-group and sex breakdown are presented from 1991 onward."