title: Epidemiological Study of Hepatitis A Infection in Eastern Bulgaria.
abstract: 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.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  We reviewed retrospectively all reported cases of acute hepatitis A in the eastern regions of Bulgaria over a 7-year period between 2008 and 2014.
  
  
  RESULTS
  A total of 2879 newly infected patients were registered during the study period, the number varying widely: from 190 cases in 2014 to 923 in 2012. The average incidence of HAV was higher in the south-eastern regions than in the northeastern regions (55.30%000 vs 15.04%000 respectively, p < 0.0001). The most affected age group in all regions was the 5-9-year olds (p < 0.0001) and males were significantly more susceptible to HAV (p = 0.02).
  
  
  CONCLUSIONS
  Hepatitis A is still a major public health problem in Bulgaria; there is a significant difference in the incidence of the disease between the regions in the south-east and those in the north-east and between the different age groups and sexes.
authors.affiliation: Department of Preclinical and Clinical Sciences, Faculty of Pharmacy, Medical University of Varna, 3 Bregalnica St., 9000 Varna.
authors.forename: Gabriela St
authors.initials: GS
authors.lastname: Tsankova
authors.affiliation: Department of Preclinical and Clinical Sciences, Faculty of Pharmacy, Medical University of Varna, 3 Bregalnica St., 9000 Varna.
authors.forename: Tatina T
authors.initials: TT
authors.lastname: Todorova
authors.affiliation: Medical College, Medical University of Varna, Varna.
authors.forename: Neli M
authors.initials: NM
authors.lastname: Ermenlieva
authors.affiliation: Medical College, Medical University of Varna, Varna.
authors.forename: Tsvetelina K
authors.initials: TK
authors.lastname: Popova
authors.affiliation: Faculty of Dental Medicine, Medical University of Varna, Varna.
authors.forename: Dayana T
authors.initials: DT
authors.lastname: Tsankova
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002031:Bulgaria / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D019353:Endemic Diseases; D005260:Female; D006506:Hepatitis A / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D017678:Sex Distribution; D055815:Young Adult
keywords: epidemiology; hepatovirus; infectious hepatitis; liver inflammation