title: Trends in vaccine-induced immunity to hepatitis B among Canadian street-involved youth.
abstract: In Canada, universal and publicly funded hepatitis B immunization programs have been available since 1998 in all provinces and territories. This present study estimates the proportion of having vaccine-induced immunity to hepatitis B virus (HBV) infection and its associated determinants among street-involved youth aged at 15-24 years old in Canada using the data collected by the Enhanced Surveillance of Canadian Street Youth. Vaccine-induced immunity was identified by blood test results of anti-HBc negative and anti-HBs positive. Of the 4,035 participants included in this study, the overall proportion of those with vaccine-induced immunity to HBV was 51.7% during the study period compared to over 90% among the general adolescent population. The proportion of street-involved youth immunized with HBV vaccine increased from 34.7% in 1999 to 64.4% in 2005. Immunity was higher among females (aOR = 1.43, 1.17-1.75) and among those with a reported history of sexually transmitted infection (aOR = 1.30, 1.03-1.63). The proportion of youth with the immunity decreased as age increased (aOR = 0.78, 0.76-0.81, per year increase). Despite an overall increase in the proportion of Canadian street-involved youth with vaccine-induced immunity to HBV, the proportion was still significantly lower than that observed in the general adolescent population. This highlights the need to improve the access to basic health care and the immunization programs to HBV for street-involved youth through creative outreach programs and other multi-faceted approaches.
authors.affiliation: Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada. ling_huang@phac-aspc.gc.ca.
authors.forename: Ling
authors.initials: L
authors.lastname: Huang
authors.affiliation: Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Marie-Line
authors.initials: ML
authors.lastname: Gilbert
authors.affiliation: Hospital for Sick Kids, University of Toronto, Toronto, ON, Canada.
authors.forename: Miriam F
authors.initials: MF
authors.lastname: Rossi
authors.affiliation: Infectious Diseases, Dalhousie University, Halifax, NS, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Haase
authors.affiliation: Public Health Services, Saskatoon Health Region, Saskatoon, SK, Canada.
authors.forename: Judith
authors.initials: J
authors.lastname: Wright
authors.affiliation: STI Services, Ottawa Public Health, Ottawa, ON, Canada.
authors.forename: Nadine
authors.initials: N
authors.lastname: Sicard
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Carole
authors.initials: C
authors.lastname: Beaudoin
authors.affiliation: STI/HIV Prevention, BC Centre for Disease Control, Vancouver, BC, Canada.
authors.forename: Darlene
authors.initials: D
authors.lastname: Taylor
authors.affiliation: STD Centre, Capital Health Region, Edmonton, AB, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Gratrix
authors.affiliation: Centre for Immunization and Respiratory Infectious Diseases, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Lisa
authors.initials: L
authors.lastname: Belzak
authors.affiliation: Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Tom
authors.initials: T
authors.lastname: Wong
authors.affiliation: Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Gayatri
authors.initials: G
authors.lastname: Jayaraman
mesh_terms: D000293:Adolescent; D002170:Canada / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006510:Hepatitis B Antibodies / Q000302:isolation & purification; D017325:Hepatitis B Vaccines / Q000627:therapeutic use*; D006515:Hepatitis B virus / Q000276:immunology*; D019694:Hepatitis B, Chronic / Q000453:epidemiology / Q000517:prevention & control*; D018453:Homeless Youth; D006801:Humans; D008297:Male; D011159:Population Surveillance; D012749:Sexually Transmitted Diseases / Q000175:diagnosis; D055815:Young Adult
chemical_list: D006510:Hepatitis B Antibodies; D017325:Hepatitis B Vaccines