Prolonged Hepatitis B surface antigen positivity in Hepatitis B vaccine recipients

Effects of hepatitis B vaccination on hepatitis B surface antigen in neonates and its change in vivo

Background

Vaccination is effective to prevent hepatitis B virus (HBV) infection. However, there is still a risk of infection after vaccination. In clinical work, we found that newborns were positive for HBV surface antigen (HBsAg) after vaccination.

Objectives

To determine the effect of hepatitis B vaccination on the detection of HBsAg trend in newborns.

Methods

We collected data at birth, history of vaccination for hepatitis B, quantitative HBsAg results, and other information about newborns born in our hospital from July 2017 to July 2020. Serum samples from healthy neonates were randomly selected to be supplemented with recombinant hepatitis B vaccine on a concentration gradient, and HBsAg was measured quantitatively.

Results

Data from 1417 neonates were included in the study; 306 (21.6%) were HBsAg positive within 8 d after vaccination, with levels ranging from 0.104 IU/mL to 0.339 IU/mL. The proportion of neonates with HBsAg-positive serum was significantly correlated with the level of hepatitis B surface antibodies (anti-HBs) in the serum of their mothers (P < 0.01). Experiments in vitro showed that the proportion of neonates with HBsAg-positive serum was correlated with the dose of the hepatitis B vaccine, and when the concentration of the hepatitis B vaccine reached 5 ng/mL and 10 ng/mL, the serum HBsAg levels showed a significant negative correlation with the original concentration of serum anti-HBs.

Conclusions

Hepatitis B vaccination can affect the level of HBsAg detected in neonatal serum, and the effect could be mitigated by delaying the measurement. Moreover, maternal anti-HBs offset the effects of neonatal vaccination on HBsAg serum levels.

Positive hepatitis B surface antigen tests due to recent vaccination: a persistent problem

BACKGROUND

Hepatitis B virus (HBV) is a common cause of viral hepatitis with significant health complications including cirrhosis and hepatocellular carcinoma. Assays for hepatitis B surface antigen (HBsAg) are the most frequently used tests to detect HBV infection. Vaccination for HBV can produce transiently detectable levels of HBsAg in patients. However, the time course and duration of this effect is unclear. The objective of this retrospective study was to clarify the frequency and duration of transient HBsAg positivity following vaccination against HBV.

METHODS

The electronic medical record at an academic tertiary care medical center was searched to identify all orders for HBsAg within a 17 month time period. Detailed chart review was performed to identify all patients who were administered HBV vaccine within 180 days prior to HBsAg testing and also to ascertain likely cause of weakly positive (grayzone) results.

RESULTS

During the 17 month study period, 11,719 HBsAg tests were ordered on 9,930 patients. There were 34 tests performed on 34 patients who received HBV vaccine 14 days or less prior to HBsAg testing. Of these 34 patients, 11 had grayzone results for HBsAg that could be attributed to recent vaccination. Ten of the 11 patients were renal dialysis patients who were receiving HBsAg testing as part of routine and ongoing monitoring. Beyond 14 days, there were no reactive or grayzone HBsAg tests that could be attributed to recent HBV vaccination. HBsAg results reached a peak COI two to three days following vaccination before decaying. Further analysis of all the grayzone results within the 17 month study period (43 results out of 11,719 tests) revealed that only 4 of 43 were the result of true HBV infection as verified by confirmatory testing.

CONCLUSIONS

Our study confirms that transient HBsAg positivity can occur in patients following HBV vaccination. The results suggest this positivity is unlikely to persist beyond 14 days post-vaccination. Our study also demonstrates that weakly positive HBsAg results often do not reflect actual HBV infection, underscoring the importance of confirmatory testing. This study also emphasizes that vaccination-induced HBsAg positives occur most commonly in hemodialysis patients.

Epidemiology of hepatitis B in Canadian blood donors

BACKGROUND

The residual risk of hepatitis B is higher than for other markers such as human immunodeficiency virus and hepatitis C virus in nonendemic countries. Evaluating the potential for further risk reduction requires a better understanding of the relationship between donor selection criteria, immigration from endemic countries, and public health vaccination strategies.

STUDY DESIGN AND METHODS

Age and sex trends of hepatitis B surface antigen (HBsAg)-positive donors from 1997 to 2006 were analyzed using a Poisson model. All HBsAg-positive donors in 2005/2006 plus four matched control donors for every HBsAg-positive donor who participated were invited to participate in a risk factor interview and predictors of HBsAg positivity identified by logistic regression. A survey of 40,000 donors who did not react for all markers asked about vaccination history and country of birth.

RESULTS

Most HBsAg-positive donations were from first-time donors (86%), have been decreasing in donors under the age of 30 (p < 0.01), and were correlated with geographic regions with more donors from higher-prevalence countries (p < 0001). Birth in a higher-prevalence country predicted HBsAg positivity (p < 0.01). Fifty-six percent of donors reported being vaccinated for hepatitis including approximately 80 percent of donors under age 30 who reported being vaccinated as part of regular school programs.

CONCLUSION

HBsAg-positive donations are decreasing in donors under age 30, those most frequently vaccinated through provincial vaccination programs. HBsAg-positive donations largely reflect immigration from high-prevalence countries without other deferrable risk factors, mainly chronic cases that will be detected by current testing. Furthermore, risk of incident infections should decrease with increasing vaccination rates in donors, especially the younger cohort now receiving universal vaccination.