Identification of Haemophilus influenzae clones associated with invasive disease in Italy by Multilocus Sequence Typing.

Department of Infectious, Parasitic and Immune-mediated Diseases. Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome-Italy.
Clinical and vaccine Immunology: CVI (Impact Factor: 2.37). 06/2013; DOI: 10.1128/CVI.00028-13
Source: PubMed

ABSTRACT The introduction of Haemophilus influenzae serotype b (Hib) conjugate vaccines has changed the epidemiology of invasive H. influenzae disease with a shift in the predominant serotype from Hib to nonencapsulated (ncHi). The objective of this study was to identify the genotypes/clones associated with invasive H. influenzae disease in Italy. Eighty-seven H. influenzae strains isolated in the years 2009-2011 within the National Surveillance of Invasive Bacterial Disease were analyzed. Strains were characterized by serotyping, antimicrobial susceptibility testing and multilocus sequence typing (MLST). Genetic polymorphisms in the blaTEM gene promoter region as well as the occurrence of both adhesin genes (hmwA and hia) and IgA1 protease-encoding gene (igaB) was also investigated.

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