The purpose of this study is to assess HBV immunity and institute policy regarding the Hepatitis B vaccination practices in the IDF among a cohort that was vaccinated during infancy.

The study population will consist of both males and females who were born after January 1st 1992, who are in medical training at the Medical Corps Training Base. Demographic information will be obtained through a questionnaire given to the soldiers in the study , as well as the IDF computerized personnel information database.

This study is designed to determine HBV vaccination policy among new HCWs in the IDF, who were vaccinated during infancy. This population was recruited to the IDF since the second half of 2010. Therefore, it is necessary to conduct this study on new HCWs that will be receiving the routine HBV vaccination and that will be at risk for HBV infection in the future due to their occupation in the army (HCWs, etc).

Inclusion Criteria:

1. Soldiers born on or after January 1st, 1992
2. Soldiers taking part in a medical training course
3. Soldiers that signed an informed consent form

Exclusion Criteria:

1. Born before January 1st, 1992
2. Soldiers with previous known infection with HBV
3. Soldiers with documented evidence of immunity against HBV
4. Soldiers that refuse to participate in the study

The study population will consist of both males and females who were born after January 1st 1992, who are in medical training at the Medical Corps Training Base.