According to the CDC, no future retesting/re-immunization is necessary once a patient has shown adequate titer response to a hepatitis B series. Even low titer levels at that point imply continued immunity. Yet this does not apply to rubella. How do you explain this?
—Deborah Herczog, RNC, ANP, MSN, Austin, Tex.
One to two months after the three-dose vaccination series for hepatitis B, a hepatitis B surface antibody (anti-HBs) level of 10 mIU/mL indicates long-term immunity. Studies show that immunologic memory remains intact for at least 23 years and confers protection against clinical illness and chronic hepatitis B virus infection even though anti-HBs levels might become low or decline below detectable levels. For rubella, the studies show that more than 90% of vaccinated persons have protection against both clinical rubella and viremia for at least 15 years. However, some reports have indicated that viremic re-infection following exposure may occur among vaccinated persons who have low levels of rubella antibody. The frequency and consequences of this phenomenon are unknown but believed to be uncommon.
—Jo Ann Deasy, PA-C, MPH (113-14)