Hepatitis B Blood Donor Screening Data: An Under-Recognized Resource for Canadian Public Health Surveillance

Abstract

Hepatitis B surveillance is essential to achieving Canada’s goal of eliminating hepatitis B by 2030. Hepatitis B rates, association of infection with vaccine age-eligibility, and risk factors were analyzed among 1,401,603 first-time Canadian blood donors from 2005 to 2020. Donors were classified as having likely chronic or likely resolved/occult infections based on hepatitis B surface antigen, anti-hepatitis B core antigen, and hepatitis B nucleic acid test results. Likely chronically infected and control donors (ratio 1:4) participated in risk-factor interviews. The 2019 rate of likely chronic infection was 61.9 per 100,000 (95% CI 46.5–80.86) and 1449.5 per 100,000 for likely resolved/occult infections (95% CI 1370.7–1531.7). Likely chronic infections were higher in males (OR 3.2; 95% CI 2.7–3.7) and the vaccine-ineligible birth cohort (OR 1.9; 95% CI 1.6–2.2). The main risk factors were living with someone who had hepatitis (OR 12.5; 95% CI 5.2–30.0) and ethnic origin from a high-prevalence country (OR 8.4; 95% CI 5.9–11.9). Undiagnosed chronic hepatitis B may be more prevalent in Canada than currently determined by traditional passive hepatitis B reporting. Blood donor data can be useful in informing hepatitis B rates and evaluating vaccination programs in Canada.

Hepatitis B virus genotype surveillance in Canadian blood donors and a referred patient population, 2016–2021

“…Patients and blood donors capture different sub‐populations [24]. Blood donors are deferred for recent risk factors, such as sexual risks, contact with hepatitis infectious sources, such as needlestick exposures, or known history of hepatitis B infection.…”

“…The median age of referred patients was slightly older than the median age of blood donors. Canadian Blood Services (CBS) has reported that donors tend to skew older, with almost half (45%) of donors over the age of 50 years [34], although first‐time donors are generally younger on average (70% are under the age of 50 years [24]). In contrast, gtE referred patients and blood donors had median and mean ages that were significantly younger than persons infected with other HBV genotypes.…”

Monitoring syphilis serology in blood donors: Is there utility as a surrogate marker of early transfusion transmissible infection behavioral risk?

“…All first-time donors with confirmed syphilis antibody results from 2005 to 2015, and from 2020 to 2021 were invited to participate in a telephone risk factor interview described elsewhere. 20 In brief, four control donors negative for all infectious markers matched by age (±5 years), sex, donation status and region were randomly selected. After notification of their syphilis positive result a letter inviting participation in the interview was sent.…”

Challenges for hepatitis B control in Asia‐Pacific areas: Consolidating vaccination and rolling‐out antiviral therapies

“…Therefore, nucleic acid test for circulating HBV DNA was introduced around year 2000 worldwide. 8,9 This new assay is more sensitive than HBsAg in detecting HBV and effectively eliminate window-period carrier donors. Currently, the PTH hepatitis B decreases to less than 1 per 100 000 in Asia-Pacific areas, and this common horizontal HBV transmission route is almost interrupted.…”

“…Currently, the PTH hepatitis B decreases to less than 1 per 100 000 in Asia-Pacific areas, and this common horizontal HBV transmission route is almost interrupted. 9…”