The aim of this study is to evaluate the prevalence of hepatitis B in Vallés Occidental. Also, describe the stage of the disease, and whether if they are under medical treatment or not.

The hepatitis B virus ( HBV ) is a global health problem . It is estimated that in the world there are about 350-400 million carriers of HBV surface antigen ( HBsAg ) 1 .

The prevalence in Spain is estimated at a 2-7 % and is considered a second intermediate prevalence.

For over 20 years, has carried out a program of primary prevention through universal vaccination against hepatitis B including it in the childhood vaccination schedule and has already been observed that in some estudi3 the prevalence has declined . For this reason , we want to evaluate what is the currently prevalence in our area of influence. There aren't recent studies to assess what is the current status of these patients ( how many , what risk factors which needs of treatment and with answer ...)

Inclusion Criteria:

• Patients with HBsAg + visited in Digestive/Hepatology outpatient visits and Hepatology of the participating hospitals

Exclusion Criteria:

• Patients < 18 aged
• Duplicity on record

The are Included consecutively for one year ( 1 June 2014 to 31 May 2015 ) all patients who are in the inclusion criteria