Immunogenicity Of Combined Hepatitis Research Articles

Safety and immunogenicity of combined hepatitis A and hepatitis B vaccine according to 0 and 6 months schedule in healthy children

To evaluate the safety and immunogenicity of the Bilive(TM) combined hepatitis A and hepatitis B vaccine in healthy children. A total of 116 healthy children aged 1 - 10 years, who, without history of hepatitis A vaccine vaccination and anti-HAV negative, had completed the full immunization of hepatitis B vaccine were recruited in city of Changzhou in Jiangsu province. The Bilive(TM) combined hepatitis A and hepatitis B vaccine was administered according to a two-dose schedule (0, 6 months). The dosage was 250 U for hepatitis A antigen and 5 microg for hepatitis B surface antigen. The potential adverse effects were observed within 72 hours after vaccination. The serum samples were collected for the testing of anti-HAV and anti-HBs at month 1, 6 and 7 after initial dose. The local and systemic adverse reactions after immunization were slight and temporary. The rates of local and systemic adverse reactions were 12.1% (14/116) and 6.0% (7/116). The sero-conversion rates of HAV were from 92.9% (92/99) to 100.0% (101/101) and the geometric mean titers (GMT) ranged from 47.0 mIU/ml to 2762.3 mIU/ml 1, 6, 7 months after initial dose. The sero-protection rate of HBV was 86.1% (87/101) before vaccination and came up to 100.0% (101/101) one month after initial dose, and the GMTs of HBV were from 894.3 mIU/ml to 3314.3 mIU/ml 1, 6, 7 months after initial dose. The Bilive(TM) combined hepatitis A and hepatitis B vaccine has good safety and immunogenicity in healthy children who had preexisting immunity to hepatitis B virus.

Comparative evaluation of the immunogenicity of combined hepatitis A and B vaccine by a prospective and retrospective trial

In the past, immunogenicity of hepatitis A and B vaccines needed to be questioned in persons of advanced age, especially in those of 40 years and older.We performed a comparative multicenter prospective and retrospective study with the combined hepatitis A and B vaccine Twinrix® to identify factors influencing the results of the vaccination in a population of all age groups.Out of 489 subjects enrolled, 241 were vaccinated in a prospective study (group 1) and 248 subjects in a retrospective study (group 2) in 17 German centers with median age of 40.1 (14-79) years. Following three applications of the combined hepatitis A/B vaccine we found 96.2% with protective antibodies against HAV and 88.7% were protected against HBV.With increasing age the subjects developed decreasing anti-HBs antibody levels whereas the seroprotection rate was significantly reduced by age (p

Immunogenicity of combined hepatitis A and B vaccine in elderly persons

More and more elderly people travel to areas where hepatitis A and B are endemic. Their immune system is less effective than in young persons. Therefore, it has to be insured that these travelers have protective immunity after vaccination.In a retrospective study we measured anti hepatitis virus (anti-HAV) and anti-HBs in elderly persons (N=104, mean age 54 years) after combined hepatitis A/B vaccination under every-day conditions. After complete vaccination only 36 (34.6%) had antibodies against both viruses. Only 23 (29%) of 80 vaccinees older than 40 years were protected against hepatitis B and 52 (65%) against hepatitis A.The response to the vaccination decreased with increasing age. Vaccination against hepatitis B—but not against hepatitis A—was also influenced by the presence of chronic disease.After one booster 87% of the anti-HAV negative vaccinees developed protective anti-HAV antibodies. Anti-HBs can be expected in about 50% of the HBV negative vaccinees with every single booster.These results indicate that combined hepatitis A/B vaccination is not very effective in elderly persons. After complete vaccination their anti-HAV and anti-HBs antibodies have to be controlled to insure protection. In case of vaccination-failure boosters are very effective.

Immunogenicity of a combined hepatitis A and B vaccine in healthy young adults

Combining several vaccines in a single formulation can change the potency of the vaccine antigens. Previous studies suggested a higher immunogenicity of a new combined hepatitis A and B vaccine compared with the monovalent hepatitis B vaccine. We investigated the immune response to hepatitis B surface antigen 1 month after the third vaccine dose in 282 healthy adults who had received either a monovalent hepatitis B vaccine ( n=148) or the combined hepatitis A/B vaccine ( n=134). A slight trend towards higher geometric mean titres of anti HBs was found at this point in time in the group immunised with the combined vaccine, especially in the few vaccinees with preexisting antibodies against hepatitis A virus. However none of these differences was statistically significant, arguing against an advantage of the combined vaccine regarding hepatitis B immunisation.

A follow-up study of combined vaccination with plasma-derived and recombinant hepatitis B vaccines in infants

This study was aimed to evaluate the efficacy and immunogenicity of combined hepatitis B vaccination with plasma-derived vaccine (PDV) and recombinant vaccine (RV). A total of 329 infants was recruited, including 224 high-risk infants born to hepatitis B e antigen-positive mothers and 105 low-risk infants born to hepatitis B e antigen-negative mothers. The high-risk infants received four doses of hepatitis B vaccine at 0, 1, 2 and 12 months of age with five different schedules. Group A1 and A2 infants were vaccinated with PDV as the first dose and RV (SB vaccine for group A1, MSD vaccine for group A2) as the remaining three doses. Group B1 and group B2 infants were vaccinated with PDV as the first two doses and RV (SB vaccine for group B1, MSD vaccine for group B2) as the remaining two doses. Group C infants received four doses of PDV. Low-risk infants were vaccinated with PDV at birth, and RV at 1 and 6 months of age (group D1, using SB vaccine; group D2, using MSD vaccine). At completion of vaccination schedules, 20 of 224 high-risk infants (9%) were positive for hepatitis B surface antigen. The overall protective efficacy was 90%. Hepatitis B surface antibody (anti-HBs)-positive rate ranged between 94 and 100% among the remaining infants. The protective efficacy and immunogenicity were similar among groups except that the mean level of anti-HBs in group C, D1 and D2 infants tended to be lower than that of the other four groups. To ensure an optimal immune response, four doses of vaccine are recommended in high-risk infants when two types of vaccine are to be used in combination.