3, 4 In addition, persons with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection who develop superinfection with HAV are at increased risk for fulminant hepatitis and associated mortality.5, 6 In human immunodeficiency virus (HIV)-infected patients who acquire HAV, the duration of HAV viremia would be longer compared with that of healthy persons,7 which may increase the risk of transmission to others. Therefore,

HAV vaccination is recommended for HIV-infected patients, injecting drug users, men who have sex with men (MSM), hemophiliacs, AZD2014 concentration patients with chronic liver disease (e.g., chronic HBV or chronic HCV infection), and persons planning to travel to or reside in endemic areas for HAV transmission.8 The response rate check details of HAV vaccination is almost 100% among HIV-uninfected persons who receive two standard doses of HAV vaccine.9, 10 However, the immunogenicity to HAV vaccination is impaired in HIV-infected patients, and the seroconversion rate is estimated to be 68% to 88.2% after two doses of HAV vaccine (each dose containing 720 or 1,440 enzyme-linked immunosorbent assay [ELISA] units) and 76% to 90% after three doses of HAV vaccine (each containing 720 ELISA units).9-14 Furthermore, the antibody titers of

HIV-infected patients following HAV vaccination (100-636 mIU/mL) are significantly lower compared with those of HIV-uninfected persons (>1,000 mIU/mL).9,

10 In a recently published 3-oxoacyl-(acyl-carrier-protein) reductase randomized clinical trial in HIV-infected patients, the three-dose schedule of HAV vaccination (each dose containing 1,440 ELISA units) tended to achieve a higher seroconversion rate than the two-dose schedule at week 72 (78.3% versus 61.2%; P = 0.07) and produce higher and more durable antibody titers after follow-up for 18 months.15 In this study, we compared the immunogenicity of two different doses of HAV vaccination (two doses versus three doses) in HIV-infected patients and evaluated whether an additional dose of HAV vaccination in HIV-infected patients could achieve a comparable serologic response to HIV-uninfected subjects. This prospective cohort study was conducted at a university hospital that is a major hospital designated for HIV care and provision of voluntary counseling and testing for HIV and sexually transmitted infections in Taiwan, where the overall seroprevalence of HAV in HIV-infected MSM was 50.5%, which rapidly increased in persons aged 30 to 40 years, suggesting an opportunity for HAV vaccination in persons younger than 40 years.16, 17 Subjects with and without HIV infection who were seronegative for HAV and aged 18 to 40 years were enrolled from June 25, 2009, to December 31, 2010. HIV-infected MSM were recruited from the outpatient clinics, while HIV-uninfected MSM were recruited from voluntary counseling and testing services.