title: Evidence for Hepatitis A virus endemic circulation in Israel despite universal toddlers' vaccination since 1999 and low clinical incidence in all age groups.
abstract: Universal toddlers vaccination (UTV) introduced in 1999, reduced hepatitis A incidence in Israel from 50.4 to <1.0/100,000. The current Hepatitis A virus (HAV) molecular epidemiology in Israel was studied 13-14y post UTV introduction..
  
  
  
  An outbreak in Tel-Aviv with 75 cases in 2012-2013 was investigated. Real-time RT-PCR and sequencing of the VP1-2A region (1100bp) was done on: a. serum samples from patients with acute Hepatitis A (12/ 75 in Tel-Aviv and 31 patients hospitalized in 3 other major cities in 2011-2013); b. in sewage samples (27 from metropolitan Tel-Aviv, 14 from the other 3 cities and 6 from Gaza).
  
  
  
  The outbreak began among intravenous drug users then spread to the general population. Patients' mean age was 33.2y, 4/75(5.3%) had been vaccinated and 58/75(77.3%) were hospitalized. No common environmental source was found. HAV was detected in sewage samples: 16/27(59.2%) from Tel-Aviv; 4/14(28.6%) collected throughout Israel and 6/6 (100%) from Gaza. Genotype IB predominated (52/53 sequenced samples) and identical strains were demonstrated in the Israeli and Palestinian populations by phylogenetic analysis.
  
  
  
  Despite the UTV success, HAV circulation in the Israeli population continues, apparently due to its close contacts with the endemic Palestinian population. Reassessment of vaccination policy is recommended.
authors.affiliation: Central Virology Laboratory, Israel Ministry of Health, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Yosef
authors.initials: Y
authors.lastname: Manor
authors.affiliation: Tel-Aviv District, Israel Ministry of Health, Tel-Aviv, Israel.
authors.forename: Matthew
authors.initials: M
authors.lastname: Lewis
authors.affiliation: Central Virology Laboratory, Israel Ministry of Health, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Daniela
authors.initials: D
authors.lastname: Ram
authors.affiliation: Liver Unit, Hadassah-Hebrew University Hospital, Jerusalem, Israel.
authors.forename: Nili
authors.initials: N
authors.lastname: Daudi
authors.affiliation: Central Virology Laboratory, Israel Ministry of Health, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Orna
authors.initials: O
authors.lastname: Mor
authors.affiliation: Tel-Aviv District, Israel Ministry of Health, Tel-Aviv, Israel.
authors.forename: Michal
authors.initials: M
authors.lastname: Savion
authors.affiliation: Virology Laboratory, Rambam Medical Center, Haifa, Israel.
authors.forename: Zipi
authors.initials: Z
authors.lastname: Kra-Oz
authors.affiliation: Laboratory of Clinical Virology, Soroka University Medical Center, Faculty of Health Sciences Ben Gurion University of the Negev, Beer-Sheva, Israel.
authors.forename: Yonat
authors.initials: Y
authors.lastname: Shemer Avni
authors.affiliation: Tel-Aviv District, Israel Ministry of Health, Tel-Aviv, Israel.
authors.forename: Rivka
authors.initials: R
authors.lastname: Sheffer
authors.affiliation: Liver Unit, Hadassah-Hebrew University Hospital, Jerusalem, Israel.
authors.forename: Daniel
authors.initials: D
authors.lastname: Shouval
authors.affiliation: Central Virology Laboratory, Israel Ministry of Health, Sheba Medical Center, Tel-Hashomer, Israel.|School of Public Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Ella
authors.initials: E
authors.lastname: Mendelson
keywords: HAV; Hepatitis A; circulation; endemic; environmental samples; epidemiology; outbreak; phylogenetic analysis; vaccination