Evaluation of Anti-HBs Antibody Immune Response against Hepatitis B virus in Vaccinated People in a North-eastern Bulgaria Region.

Introduction: Hepatitis B virus (HBV) is one of the most significant human pathogens responsible for a huge number of acute and chronic liver infectious diseases worldwide.

Aim: To find the duration of post-vaccination immune response in individuals allocated to five age groups from 6 months to 20 years.

Materials And Methods: All tested subjects were born between 1999 and 2018 and therefore covered by the compulsory vaccination program against hepatitis B.

Epidemiological Study of Hepatitis A Infection in Eastern Bulgaria.

Background: Hepatitis A virus (HAV) infection is an acute, self-limited liver disease transmitted usually through the faecal-oral route via person-to-person contact. Bulgaria has intermediate HAV endemicity with higher susceptibility among adults and recurrent outbreaks.

Aim: As HAV infection is strongly related to human movements and represents a significant risk to travelers and migrants, as well as to local population receiving these groups, we set out to analyze the epidemiological data on hepatitis A in five of the largest tourist border regions of Bulgaria located in its eastern part: Varna, Shumen, Dobrich, Burgas and Yambol.