We did a hepatitis B panel for a new hospital employee from Gambia. She had no documentation of having been vaccinated. Her results showed HBsAg nonreactive, anti-HBc reactive, IgM anti-HBc nonreactive, and anti-HBs borderline. We don’t know how to interpret these results. Should she be immunized?

Most likely this person has a resolved HBV infection and is immune. However, it would be preferable to test her again for all these serologic markers, and also quantify the anti-HBs result. If the results are still positive for anti-HBc, and anti-HBs is less than the immune level of 10 mIU/mL, you can give her one dose of HepB vaccine and test again in 1–2 months. If the anti-HBs is positive (10 mIU/mL or higher), she is immune. No further action is needed other than to document the results. If the anti-HBs is still negative, complete the vaccine series and test again 1–2 months after the last dose of vaccine.