To improve the knowledge on influenza and respiratory syncytial virus (RSV) infections burden on paediatric population, a cohort of 1600 Italian children was prospectively followed up during the 2001–2002 and 2002–2003 winters. Specimens from each influenza-like illness (ILI) were collected and tested for influenza viruses and RSV by PCR and cell cultures. Two hundred sixty-eight and 440 episodes of ILI were registered during 2001–2002 and 2002–2003, with a cumulative incidence of 16.8% and 27.5%, respectively. A comparison between the morbidity data of this well-studied cohort and those of the national network (Influnet) and the one between different swabs and different detection methods was performed. Considering the high variability of respiratory epidemics in different areas, the cumulative morbidity is not far from that observed in the Liguria region by the national network (21.1% and 24.6%). Fifty-nine (22%) and 22 (8.3%) out of 268 specimens collected during 2001/2002 season and 60 (13.6%) and 34 (7.2%) out of 440 during 2002/2003 were influenza and RSV-PCR positive, respectively. During the former winter, influenza B virus was prominent, while during the last season A/H3N2 predominated. RSV circulation preceded influenza detection in both seasons. PCR confirmed higher sensitivity than cell culture in influenza virus detection; the combination of a paediatric sentinel-based network with virological surveillance performed by reverse transcription polymerase chain reaction (RT-PCR) for influenza and RSV seem a good way for the control of respiratory tract diseases.

During the 2002/2003 season, Italian sentinel-based network for surveillance of influenza, coordinated by Inter-university (Genoa-Milan-Trieste) Centre for Influenza Research (CIRI) registered an increasing incidence from week 9/2003 (10.3 cases per 1000). The epidemic curve highlighted different incidences in the three ages group: morbidity rate was higher in children (24.4 cases/1000, at week 9/2003) than in adults (8.8 cases/1000) and in >65 year group (5.1 cases/1000) in which high vaccination coverage was reached. It is noteworthy that, in this age group, laboratory-confirmed cases in immunized subjects and outbreaks in nursing homes where the vaccine coverage is close to 100% were registered. The rapid increase of influenza activity was characterized by the co-circulation of A/H3N2/Toulouse/878/01-like viruses, similar to the vaccine strain A/Moscow/10/99, and new strains that have different antigenic properties with respect to the H3N2 vaccine strain and the major 2001/02 epidemic A/H3N2 strains (A/Panama/2007/99 and A/Toulouse/878/01). The results of HI test showed that viruses isolated in Northern Italy gave reduced titres with antisera to vaccine strain and recent reference strains. Molecular characterization of the gene HA allowed the identification of new variants belonging to the cluster clearly separated from the strains circulated in the previous seasons. The new sequences are similar to that of A/HongKong/1143/02, previously isolated in Asia and USA and not yet circulating in Europe. At least two amino acid changes were observed over A, B, D, and E antigenic sites and 1–2 over C site relative to A/Moscow10/99. These substitutions suggest the possibility of sub-optimal protection of the A/H3N2 component in immunised subjects. Considering these molecular data and the HI test findings, the new variant isolates in Northern Italy might escape from the immunological pressure induced by vaccination and previous infections, representing the potentially epidemic strain.

Several experimental and clinical studies have demonstrated a direct bronchoconstrictor effect of opioids on smooth bronchial musculature followingiv administration. The aim of this study was to evaluate the effects of alfentanil on respiratory system mechanics in a group of ASA I patients ventilated mechanically during general anesthesia.