Table 1. Case definitions for HCV, HBV, HIV and active TB.

Infection	Case definition
HCV Case	a confirmed anti-HCV positive test OR
	a confirmed HCV RNA positive test OR
	an HCV genotype result OR
	a confirmed public health HCV case report in iPHIS [7]
HIV Case	Any one of the following was considered an HIV case:
	1. Laboratory confirmation based on provincial HIV test interpretation guidelines [8]:
	HIV antibody by screening test (i.e., ELISA) followed by positive confirmatory test (i.e., Western Blot or Nucleic Acid Amplification Test), OR
	detection of HIV nucleic acid (RNA or DNA) OR
	detection of p24 antigen with confirmation by neutralization assay, OR
	isolation of HIV in culture.
	2. a confirmed HIV case report in HAISYS
	3. three physician claims or one hospital admission with diagnosis of HIV using ICD 9/10 codes: MSP: ICD-9 code starting with 042, 043, 044, or codes V08, 795.71, 795.8 or 07953; DAD: ICD9–CM codes starting with 042, 043, 044, or codes V08, 795.71, 795.8 or 07953; ICD-10-CA codes: B20–B24, F024, R75, Z21, O987, B9735.
HBV Case	a confirmed public health HBV case report recorded in iPHIS defined on the basis of provincial guidelines [10].
Active TB Case	a confirmed public health active TB case report recorded in iPHIS [11].

iPHIS: Integrated Public Health Information System; HAISYS: HIV/AIDS Information System; MSP: Medical Services Plan; DAD: Discharge Abstract Database.