This case was reported in a literature article and described the occurrence of vaccination failure in a infant male subject who received Hepatitis B vaccine. Co-suspect products included Hepatitis B Immunoglobulin. On an unknown date, unknown after receiving Hepatitis B vaccine, the subject developed vaccination failure. Serious criteria included GSK medically significant. Additional event(s) included hepatitis B with serious criteria of GSK medically significant and vertical infection transmission. The outcome of vaccination failure was unknown. The outcome(s) of the additional event(s) included hepatitis B (unknown) and vertical infection transmission (unknown). The investigator considered that there was a reasonable possibility that the vaccination failure, hepatitis B and vertical infection transmission may have been caused by Hepatitis B vaccine. Relevant Tests: Lab tests performed on unspecified dates between 2005 and 2011. In this study, the Advisory Committee on Immunization Practices recommends that infants born to HBsAg-positive mothers should underwent post vaccination serologic testing including testing for HBsAg (infection) and antibody to  HBsAg (immunity) between 9-18 mo of age. Diagnostic results (unless otherwise stated, normal values were not provided): On an unknown date, Hepatitis B surface antigen result was positive unknown. Additional information was provided. This case was reported in a literature article and described the suspected vaccination failure in a male infant who was vaccinated with unspecified hepatitis B virus (HBV) vaccine (manufacturer unknown). The patient was a part of retrospective analysis among infants born to hepatitis B surface antigen (HBsAg)-positive mothers who received post vaccination serologic testing (PVST) between 2005 and 2011.  The study was to evaluate the effect of maternal HBeAg status and HBV DNA levels on perinatal HBV infection. The patient was among cases group. The patient was born between 1 January 2005 and 31 December 2011. The patient's mother was HBeAg-positive and had an HBV DNA level of 1 x 10E5  IU/mL. The mother's laboratory results were available 24 days prior to delivery. The patient was born at term via normal spontaneous vaginal delivery. No information on patient's medical history or concurrent condition or concomitant medication was provided. On an unspecified date, the patient received unspecified HBV vaccine (administration route and site unspecified; dosages unknown; batch number not provided). It was reported that the patient had received appropriate post-exposure prophylaxis (PEP) at birth and completed the HBV vaccine series in the appropriate time period. [In this study, ACIP also recommends that infants born to HBsAg-positive mothers receive post-exposure prophylaxis (PEP) including hepatitis B immunoglobulin (HBIG) and the first dose of HBV vaccine within 12 h of birth; complete the HBV vaccine series; and receive postvaccination serologic testing (PVST), including testing for HBsAg (infection) and antibody to HBsAg (immunity) between 9-18 mo of age]. Age of vaccination was not reported. On an unspecified date between 2005 and 2011, an unknown period after vaccination, the patient underwent PSVT. Subsequently, the patient was found positive for HBsAg-positive. This case has been considered as suspected vaccination failure being the time to onset was unknown. This case has been considered serious due to suspected vaccination failure. Treatment was unknown. The outcome of the event was not reported. The authors did not comment on the relationship between the event of perinatal hepatitis B virus (HBV) infection and unspecified HBV vaccine. The authors concluded, "In this area, transmission is low and most infected infants receive appropriate PEP and vaccination. Maternal HBV DNA equal to or more than 2 x 10E7 IU/mL is associated with high risk of perinatal infection." This is 1 of the 2 valid cases in this literature article.