The purpose of this study is :

• To evaluate prevalence of protective hepatitis B antibody comparing intradermal (ID) and intramuscular (IM) route in antiHbsAb negative HIV infected children treated with highly active antiretroviral therapy (HAART)
• To revaccinate the HBV vaccine in the children who didn't have protective HBV Ab

Hepatitis B virus (HBV) and HIV share the same route of transmission and can have co-infection. The prevalence of this co-infection was 8.7% in Thai adult[1, 2] and 12.1% in African HIV vertically transmitted children[3]. Occurrence of HBV has effects to treatment due to having the same medication, lamivudine, tenofovir, emtricitabine or entecavir, to anti HIV medication. HBV can cause chronic liver disease, cirrhosis and hepatocellular carcinoma.

In Thailand, the routine HBV vaccination program was started since 1992. Few reports in severe immune compromise HIV children has been shown to lose their expected preventive measles and hepatitis B antibody from history of scheduled vaccination even after the immune recovery by HAART[4, 5]. Limited data in of prevalence of protective hepatitis B antibody response after immune recovery in Thai HIV infected children treated with highly active antiretroviral therapy. In addition, HBV revaccination in this group of children should be considered[6].

The response of HBV revaccination intramuscularly (IM) at 0, 2 and 6 months in 63 HIV children shown response rates 17.4, 82.5, and 92.1% at 2, 6 and 7 months respectively[6]. Protective anti-HBs were shown in the majority of non-responders to IM HBV vaccine health care workers [21/23 (91.3%)] by two doses of intradermal route (ID)[7].

We hypothesize to see the faster and higher response of antiHBs after first dose of ID compare to IM in anti HBsAb negative HIV infected children. No randomized control trial compare antibody response between IM and ID route in HIV children after immune recovery. The benefit from this trial would be decreased the vaccine cost for resourced limited country.

Inclusion Criteria:

• HIV infected individuals
• Age 1-18 years
• Current CD4 within 6 months ≥ 15% or ≥ 200 cells/ml in children age ≥ 6 years
• Signed written informed consent
• Negative HBs Ag, antiHBs, and antiHBc at screening visit

Exclusion Criteria:

• Active AIDS
• Active opportunistic infection
• Platelet < 50,000/ mm3 at screening visit
• History of hypersensitivity to HBV vaccine
• Using oral steroid or immunosuppressive drugs