Hepatitis B Virus Antibody Levels 7 to 9 Years after Booster Vaccination in Alaska Native Persons

Abstract

Hepatitis B antibody persistence was assessed in individuals who had previously received a vaccine booster. We measured hepatitis B surface antigen antibody (anti-HBs) levels 7 to 9 years post-hepatitis B booster in individuals with primary vaccination at birth. While 95 (91.3%) of 104 participants had detectable anti-HBs (minimum, 0.1 mIU/ml; maximum, 1,029 mIU/ml), only 43 (41%) had protective levels of >10 mIU/ml. Pre-and week 4 postbooster anti-HBs levels were significant predictors of hepatitis B immunity at follow-up (P < 0.001). Almost all participants had detectable anti-HBs 7 to 9 years after the hepatitis B vaccine booster, but less than half had levels >10 mIU/ml. R outine infant hepatitis B vaccination has substantially reduced the incidence of acute hepatitis B virus (HBV) infection and the prevalence of chronic infection (1, 2). However, the duration of protection following infant vaccination is unknown (3, 4). In studies from a variety of settings conducted up to 22 years after a primary vaccine series, 23% to 66% of vaccinated infants had low or undetectable concentrations of hepatitis B virus surface antibody (anti-HBs), the serologic marker of immunologic protection (5-7). Although antibody levels in many participants were below the level considered protective, most individuals likely remained immune, as shown by the infrequent serologic evidence of hepatitis B virus infection. Furthermore, individuals with evidence of breakthrough infection (the presence of antibody to hepatitis B virus core antigen [anti-HBc]) did not develop acute symptomatic or chronic HBV infection if they responded to the primary vaccine series (5).Individuals with undetectable levels of anti-HBs may retain HBV-specific immune memory. Humoral evidence of immune memory in previously vaccinated persons is demonstrable by administering a single challenge dose of vaccine and measuring the anti-HBs response. A rapid increase in anti-HBs titers represents an anamnestic response and indicates the presence of HBV-specific immune memory (3,4,8). We previously reported anti-HBs responses after administration of a booster dose of hepatitis B vaccine among children and adolescents aged 7 to 14 years who were born to HBsAg-negative women in Anchorage, Alaska, were vaccinated starting at birth, and had no HBsAg-positive persons living in their household at that time (9). Although the majority of participants had no serologic evidence of protective immunity at baseline, the absence of symptomatic or chronic infections and the presence of anamnestic responses to a challenge dose indicated that immune memory remained intact for most participants (9). Our aim was to determine the persistence of markers of HBV immunity in these individuals 7 to 9 years after they received a hepatitis B vaccine booster. MATERIALS AND METHODSParticipants. All participants were part of the original "Youth Hepatitis B Protection Study" consisting of 389 children of HBsAg-negative mothers who received three doses of hepatitis B vaccine starting at birth followed...

Efficacy of antigen dosage on the hepatitis B vaccine response in infants born to hepatitis B-uninfected and hepatitis B-infected mothers

“…Some studies have suggested that the levels of anti-HBs decrease after a full HB vaccination schedule [34]. Further studies are needed to evaluate the persistence of immune responses generated by 10 and 5 g HB vaccines.…”

Evaluation of response to hepatitis B vaccine in iranian 6–18-year-old students

“…[ 3 4 ] In the Middle East and North Africa, the prevalence of HBV infection is different such as 7.4% in Iran, 9.8% in Egypt, 6.9% in Libya, 2.4% in Lebanon, 2.6% in Palestine, 8.6% in Israel, and 6.1% in Saudi Arabia. [ 5 ] In North America, 41% had anti-hepatitis B surface (HBs) levels of >10 mIU/ml 7–9 years after booster vaccination at birth,[ 6 ] even 51% had these protective levels 30 years after receiving the primary series without subsequent doses. [ 7 ]…”

Characteristics of immune memory 10–15 years after primary hepatitis B vaccination

“…In studies in which immune memory was shown by means of the increase in anti-HBs after booster vaccination, anti-HBs titres were mostly measured only once and at rather different time points, ranging from 10 days to 2 months post-booster [7,[18][19][20][21]. In addition, in some studies anamnestic response was defined as an increase in anti-HBs to ≥10 IU/l [21][22][23][24][25], in other studies as 4-fold increase in anti-HBs [5], and sometimes both criteria were applied [13,15,20,26]. Because of the differing definitions, it seems to be impossible to differentiate in all cases between anamnestic responses due to the presence of immune memory and primary responses after loss of immune memory.…”