title: Imported arboviral infections in Italy, July 2014-October 2015: a National Reference Laboratory report.
abstract: Imported cases of infections due to Dengue (DENV) and Chikungunya (CHIKV) viruses and, more recently, Zika virus (ZIKV) are commonly reported among travelers returning from endemic regions. In areas where potentially competent vectors are present, the risk of autochthonous transmission of these vector-borne pathogens is relatively high. Laboratory surveillance is crucial to rapidly detect imported cases in order to reduce the risk of transmission. This study describes the laboratory activity performed by the National Reference Laboratory for Arboviruses (NRLA) at the Italian National Institute of Health in the period from July 2014 to October 2015.
  
  
  
  Samples from 180 patients visited/hospitalized with a suspected DENV/CHIKV/ZIKV infection were sent to the NRLA from several Italian Hospitals and from Regional Reference Laboratories for Arboviruses, in agreement with the National Plan on human surveillance of vector-borne diseases. Both serological (ELISA IgM test and Plaque Reduction Neutralization Test-PRNT) and molecular assays (Real Time PCR tests, RT-PCR plus nested PCR and sequencing of positive samples) were performed.
  
  
  
  DENV infection was the most frequently diagnosed (80 confirmed/probable cases), and all four genotypes were detected. However, an increase in imported CHIKV cases (41 confirmed/probable cases) was observed, along with the detection of the first ZIKV cases (4 confirmed cases), as a consequence of the recent spread of both CHIKV and ZIKV in the Americas.
  
  
  
  Main diagnostic issues highlighted in our study are sensitivity limitations of molecular tests, and the importance of PRNT to confirm serological results for differential diagnosis of Arboviruses. The continuous evaluation of diagnostic strategy, and the implementation of laboratories networks involved in surveillance activities is essential to ensure correct diagnosis, and to improve the preparedness for a rapid and proper identification of viral threats.
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Fortuna
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Remoli
authors.affiliation: National Center for Epidemiology and Health Promotion, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Rizzo
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Benedetti
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Fiorentini
authors.affiliation: National Center for Epidemiology and Health Promotion, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Bella
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Argentini
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Farchi
authors.affiliation: Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani, IRCCS, Rome, Italy.
authors.forename: Concetta
authors.initials: C
authors.lastname: Castilletti
authors.affiliation: Laboratory of Virology, National Institute for Infectious Diseases Lazzaro Spallanzani, IRCCS, Rome, Italy.
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Capobianchi
authors.affiliation: Infectious and Tropical Diseases Unit, Careggi University Hospital, Florence, Italy.|Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Zammarchi
authors.affiliation: Infectious and Tropical Diseases Unit, Careggi University Hospital, Florence, Italy.|Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bartoloni
authors.affiliation: Clinical Microbiology, Virology and Bioemergency, Luigi Sacco Hospital, Milan, Italy.
authors.forename: Nadia
authors.initials: N
authors.lastname: Zanchetta
authors.affiliation: Clinical Microbiology, Virology and Bioemergency, Luigi Sacco Hospital, Milan, Italy.
authors.forename: Maria Rita
authors.initials: MR
authors.lastname: Gismondo
authors.affiliation: Virology Section and Retrovirus Centre of the Department of Translational Research NSMT, University of Pisa, Pisa University Hospital (Azienda Ospedaliero-Universitaria Pisana), Pisa, Italy.
authors.forename: Luca Ceccherini
authors.initials: LC
authors.lastname: Nelli
authors.affiliation: Department of Laboratory Diagnosis, Palermo University Hospital (Azienda Ospedaliera Universitaria Policlinico Palermo), Palermo, Italy.
authors.forename: Giustina
authors.initials: G
authors.lastname: Vitale
authors.affiliation: Clinic of Infection Diseases, Department of Medicine, University of Perugia, Perugia, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Baldelli
authors.affiliation: Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy.|Institute for Maternal and Child Health-IRCCS Burlo Garofolo, Trieste, Italy.
authors.forename: Pierlanfranco
authors.initials: P
authors.lastname: D'Agaro
authors.affiliation: UOC Microbiology and Virology, Hospital for Infectious Diseases "D. Cotugno", AO dei Colli (Monaldi, Cotugno, CTO), Naples, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sodano
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rezza
authors.affiliation: Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy. giulietta.venturi@iss.it.
authors.forename: Giulietta
authors.initials: G
authors.lastname: Venturi
mesh_terms: D065632:Chikungunya Fever / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics / Q000635:transmission; D002646:Chikungunya virus / Q000235:genetics / Q000302:isolation & purification*; D003715:Dengue / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics / Q000635:transmission; D003716:Dengue Virus / Q000235:genetics / Q000302:isolation & purification*; D004196:Disease Outbreaks / Q000517:prevention & control; D005260:Female; D005838:Genotype; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D011159:Population Surveillance; D011634:Public Health; D014195:Travel; D055815:Young Adult; D000071244:Zika Virus / Q000235:genetics / Q000302:isolation & purification*; D000071243:Zika Virus Infection / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control / Q000635:transmission