title: The Molecular Epidemiology and Evolutionary Dynamics of Influenza B Virus in Two Italian Regions during 2010-2015: The Experience of Sicily and Liguria.
abstract: Molecular epidemiology of influenza B virus remained poorly studied in Italy, despite representing a major contributor to seasonal epidemics. This study aimed to reconstruct the phylogenetic relationships and genetic diversity of the hemagglutinin gene sequences of 197 influenza B strains circulating in both Southern (Sicily) and Northern (Liguria) Italy between 2010 and 2015. Upper respiratory tract specimens of patients displaying symptoms of influenza-like illness were screened by real-time RT-PCR assay for the presence of influenza B virus. PCR-positive influenza B samples were further analyzed by sequencing. Neighbor-joining phylogenetic trees were constructed and the amino-acid alignments were analyzed. Phylogenetic analysis showed clusters in B/Victoria clade 1A/1B (n = 29, 14.7%), and B/Yamagata clades 2 (n = 112, 56.8%) and 3 (n = 56, 28.4%). Both influenza B lineages were found to co-circulate during the study period, although a lineage swap from B/Victoria to B/Yamagata occurred in Italy between January 2011 and January 2013. The most represented amino-acid substitutions were N116K in the 120-loop (83.9% of B/Yamagata clade 3 strains) and I146V in the 150-loop (89.6% of B/Victoria clade 1 strains). D197N in 190-helix was found in almost all viruses collected. Our findings provide further evidence to support the adoption of quadrivalent influenza vaccines in our country.
authors.affiliation: Department of Health Promotion Sciences and Mother-Child Care "G. D'Alessandro"-Hygiene Section, University of Palermo, Palermo 90127, Italy. fabio.tramuto@unipa.it.|Clinical Epidemiology Unit, University Hospital "Paolo Giaccone", Palermo 90127, Italy. fabio.tramuto@unipa.it.
authors.forename: Fabio
authors.initials: F
authors.lastname: Tramuto
authors.affiliation: Department of Health Sciences, University of Genoa, Genoa 16132, Italy. andrea.orsi@unige.it.|Hygiene Unit, IRCCS University Hospital "San Martino"-IST National Institute for Cancer Research, Genoa 16132, Italy. andrea.orsi@unige.it.
authors.forename: Andrea
authors.initials: A
authors.lastname: Orsi
authors.affiliation: Department of Health Promotion Sciences and Mother-Child Care "G. D'Alessandro"-Hygiene Section, University of Palermo, Palermo 90127, Italy. carmelo.maida@unipa.it.
authors.forename: Carmelo Massimo
authors.initials: CM
authors.lastname: Maida
authors.affiliation: Department of Health Promotion Sciences and Mother-Child Care "G. D'Alessandro"-Hygiene Section, University of Palermo, Palermo 90127, Italy. claudio.costantino01@unipa.it.
authors.forename: Claudio
authors.initials: C
authors.lastname: Costantino
authors.affiliation: Department of Health Sciences, University of Genoa, Genoa 16132, Italy. cecilia.trucchi@edu.unige.it.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Trucchi
authors.affiliation: Department of Health Sciences, University of Genoa, Genoa 16132, Italy. cristiano.alicino@unige.it.
authors.forename: Cristiano
authors.initials: C
authors.lastname: Alicino
authors.affiliation: Department of Health Promotion Sciences and Mother-Child Care "G. D'Alessandro"-Hygiene Section, University of Palermo, Palermo 90127, Italy. francesco.vitale@unipa.it.|Clinical Epidemiology Unit, University Hospital "Paolo Giaccone", Palermo 90127, Italy. francesco.vitale@unipa.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Vitale
authors.affiliation: Department of Health Sciences, University of Genoa, Genoa 16132, Italy. filippo.ansaldi@unige.it.|Hygiene Unit, IRCCS University Hospital "San Martino"-IST National Institute for Cancer Research, Genoa 16132, Italy. filippo.ansaldi@unige.it.
authors.forename: Filippo
authors.initials: F
authors.lastname: Ansaldi
mesh_terms: D005075:Biological Evolution; D014644:Genetic Variation; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics*; D006801:Humans; D009981:Influenza B virus / Q000235:genetics*; D007251:Influenza, Human / Q000453:epidemiology* / Q000821:virology*; D007558:Italy / Q000453:epidemiology; D017720:Molecular Epidemiology; D010802:Phylogeny; D012802:Sicily / Q000453:epidemiology
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus
keywords: Italy; Liguria; Sicily; influenza B; influenza-like illness; lineages; molecular epidemiology; surveillance; viral evolution