Background: It is currently recommended that hepatitis B virus (HBV) vaccine be provided for every HIV-infected patient with no HBV immunity. HBV immunization program for HIV-infected patients was suggested to be given in three doses of vaccine at zero, one and six months. HBV vaccine has been included in the Thai immunization program for newborns for three doses, at birth, M2, and M6. Hence, one dose of vaccination might respond in complete protective immunity in some of the HIV patients.

Objective: To evaluate HIV-infected patients’ response to one dose of vaccine and their associated factors.

Materials and Methods: The present study was a Retrospective Cohort Study. It recruited patients who had come to Queen Savang Vadhana Memorial Hospital for their hepatitis B vaccination between January 1, 2018 and March 31, 2020. Eligible patients were infected with HIV, received ART, and had CD4 of more than 200 cells/mm³. The authors collected data from the patients having anti-HBs of less than 10 mIU/mL with negative anti-HBc who received HBV vaccine. From the medical records, the authors evaluated their anti-HBs titer after the first dose of vaccination, and the titer after a third dose, in cases the result of the first dose was negative.

Results: Of the 88 HIV-infected patients who received HBV vaccination, 19 patients (21.6%) showed protective anti-HBs after the first dose of vaccination. Factors associated with the presence of anti-HBs after the first dose included age as the patients of 29 years or older had protective anti-HBs of 15% and the patients younger than 29 years old had protective anti-HBs of 43% (p=0.013), and anti-HBs titer before the vaccination as the patients with titer of less than 2 mIU/mL had protective anti-HBs of 17% and the patients with titer of 2 to less than 10 mIU/mL had protective anti-HBs of 44% (p=0.038).

Conclusion: Some HIV-infected patients have developed protective anti-HBs after the first dose of HBV vaccination especially the younger age of less than 29 years old and with an anti-HBs titer before vaccination of 2 mlU/mL or above. Almost half of them required only one HBV booster to achieve protective anti-HBs.

Keywords: Vaccine; Hepatitis B; HIV; Vaccination; Immunity

Received 29 June 2021 | Revised 6 September 2021 | Accepted 15 September 2021