title: Enhanced HIV-1 surveillance using molecular epidemiology to study and monitor HIV-1 outbreaks among intravenous drug users (IDUs) in Athens and Bucharest.
abstract: BACKGROUND
  A significant increase in HIV-1 diagnoses was reported among Injecting Drug Users (IDUs) in the Athens (17-fold) and Bucharest (9-fold) metropolitan areas starting 2011.
  
  
  METHODS
  Molecular analyses were conducted on HIV-1 sequences from IDUs comprising 51% and 20% of the diagnosed cases among IDUs during 2011-2013 for Greece and Romania, respectively. Phylodynamic analyses were performed using the newly developed birth-death serial skyline model which allows estimating of important epidemiological parameters, as implemented in BEAST programme.
  
  
  RESULTS
  Most infections (>90%) occurred within four and three IDU local transmission networks in Athens and Bucharest, respectively. For all Romanian clusters, the viral strains originated from local circulating strains, whereas in Athens, the local strains seeded only two of the four sub-outbreaks. Birth-death skyline plots suggest a more explosive nature for sub-outbreaks in Bucharest than in Athens. In Athens, two sub-outbreaks had been controlled (Re<1.0) by 2013 and two appeared to be endemic (Re∼1). In Bucharest one outbreak continued to expand (Re>1.0) and two had been controlled (Re<1.0). The lead times were shorter for the outbreak in Athens than in Bucharest.
  
  
  CONCLUSIONS
  Enhanced molecular surveillance proved useful to gain information about the origin, causal pathways, dispersal patterns and transmission dynamics of the outbreaks that can be useful in a public health setting.
authors.affiliation: National Retrovirus Reference Center, Medical School, University of Athens, Athens, Greece. Electronic address: dparask@med.uoa.gr.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Paraskevis
authors.affiliation: Molecular Diagnostics Laboratory, National Institute for Infectious Diseases, Bucharest, Romania.
authors.forename: Simona
authors.initials: S
authors.lastname: Paraschiv
authors.affiliation: National Retrovirus Reference Center, Medical School, University of Athens, Athens, Greece.
authors.forename: Vana
authors.initials: V
authors.lastname: Sypsa
authors.affiliation: Hellenic Center for Diseases Control and Prevention, Athens, Greece.
authors.forename: Georgios
authors.initials: G
authors.lastname: Nikolopoulos
authors.affiliation: Hellenic Center for Diseases Control and Prevention, Athens, Greece.
authors.forename: Chryssa
authors.initials: C
authors.lastname: Tsiara
authors.affiliation: Department of Zoology, University of Oxford, UK; Virus Reference Department, Colindale, Public Health England, UK.
authors.forename: Gkikas
authors.initials: G
authors.lastname: Magiorkinis
authors.affiliation: Medical School, University of Athens, Athens, Greece.
authors.forename: Mina
authors.initials: M
authors.lastname: Psichogiou
authors.affiliation: National Retrovirus Reference Center, Medical School, University of Athens, Athens, Greece.
authors.forename: Andreas
authors.initials: A
authors.lastname: Flampouris
authors.affiliation: Molecular Diagnostics Laboratory, National Institute for Infectious Diseases, Bucharest, Romania.
authors.forename: Mariana
authors.initials: M
authors.lastname: Mardarescu
authors.affiliation: Molecular Diagnostics Laboratory, National Institute for Infectious Diseases, Bucharest, Romania.
authors.forename: Iulia
authors.initials: I
authors.lastname: Niculescu
authors.affiliation: Molecular Diagnostics Laboratory, National Institute for Infectious Diseases, Bucharest, Romania.
authors.forename: Ionelia
authors.initials: I
authors.lastname: Batan
authors.affiliation: Medical School, University of Athens, Athens, Greece.
authors.forename: Meni
authors.initials: M
authors.lastname: Malliori
authors.affiliation: Molecular Diagnostics Laboratory, National Institute for Infectious Diseases, Bucharest, Romania.
authors.forename: Dan
authors.initials: D
authors.lastname: Otelea
authors.affiliation: National Retrovirus Reference Center, Medical School, University of Athens, Athens, Greece.
authors.forename: Angelos
authors.initials: A
authors.lastname: Hatzakis
mesh_terms: D004196:Disease Outbreaks / Q000145:classification* / Q000517:prevention & control; D006115:Greece / Q000453:epidemiology; D015658:HIV Infections / Q000453:epidemiology* / Q000635:transmission; D015497:HIV-1 / Q000145:classification / Q000235:genetics*; D006801:Humans; D017720:Molecular Epidemiology; D010802:Phylogeny; D058974:Phylogeography; D062486:Public Health Surveillance / Q000379:methods*; D012367:RNA, Viral / Q000032:analysis; D012383:Romania / Q000453:epidemiology; D015819:Substance Abuse, Intravenous / Q000821:virology*
chemical_list: D012367:RNA, Viral
keywords: Effective reproductive number; Enhanced surveillance HIV-1; IDUs; Molecular epidemiology; Phylodynamics