These results demonstrate that a regular, long-term intake of various synbiotics may improve health by reducing the incidence and severity of respiratory diseases during the cold season.

Background Besides seasonal influenza viruses (IV), several other pathogens—including respiratory syncytial virus (RSV)—are involved in clinically undistinguished influenza‐like illnesses (ILIs). This study aimed at investigating the contribution of RSV in ILI cases in Lombardy (Northern Italy) during four consecutive winter seasons. Materials and Methods In the framework of influenza surveillance, respiratory samples from ILI outpatients were collected from 2014‐2015 to 2017‐2018 season. IV‐negative swabs were included in the study and analyzed to detect and molecularly characterize RSV‐A and RSV‐B. Results A total of 12.9% (135/1047) of samples were positive to RSV that was mostly detected among children ≤5 years (51/183, 27.8%) and those aged 6 to 15 years (30/158, 18.9%), whereas elderly >65 years accounted for 12% of RSV cases (15/125). The median start of RSV epidemic was in the end of November, with a peak in mid‐February and a width of nearly 4 months, almost overlapping seasonal influenza epidemic. RSV‐A and RSV‐B co‐circulated in all considered seasons, with RSV‐B predominating on RSV‐A (63.6% vs 36.4%; P < .001). Most (85.2%) RSV‐A belonged to genotype ON1 and the remaining to NA1. All RSV‐B clustered within the BA genotype. Conclusions In this study, RSV significantly contributed to ILI cases, especially among pediatric population (<15 years), although it was detected in all age groups. RSV‐B predominated on RSV‐A, and the most recent evolved genotypes (BA and ON1, respectively) circulated. Investigating the epidemiological and molecular characteristics of RSV in ILI cases can increase baseline epidemiological information before the introduction of RSV vaccination.

The immunogenicity of an anti-influenza vaccine was assessed in 409 former intravenous drug user volunteers and its effect on the levels of HIV-1 RNA, proviral DNA and on CD4+ lymphocyte counts in a subset HIV-1-positive subjects was measured. HIV-1-positive individuals (n = 72) were divided into three groups on the basis of their CD4+ lymphocyte counts, while the 337 HIV-1-negative participants were allocated into group four. Haemagglutination inhibiting (HI) responses varied from 45.8 to 70% in the HIV-1-positive subjects and were significantly higher in group four (80.7% responses to the H1N1 strain, 81.6% to the H3N2 strain, and 83% to the B strain). The percentage of subjects with HI protective antibody titres (> or = 1:40) increased significantly after vaccination, especially in HIV-1 uninfected subjects. Immunization caused no significant changes in CD4+ counts and in neither plasma HIV-1 RNA nor proviral DNA levels. Therefore, vaccination against influenza may benefit persons infected by HIV-1.

As the regional influenza reference centre operating within the Italian network InfluNet, here we report data on virological and epidemiological surveillance of influenza, as well as on the vaccination coverage rates achieved in Lombardy (Northern Italy) over 10 consecutive winter seasons (2004-2014).   Over the past 10 years, influenza vaccine coverage declined both in the general population (from 15.7% in 2004-2005 to 11.7% in 2013-2014) and in the vaccine-target population of individuals ≥65-y-of-age (from 65.3% in 2004-2005 to 48.6% in 2013-2014) and is far below the minimum planned threshold level (75%). The highest influenza-like illness (ILI) rates were recorded during the 2004-2005 and 2009-2010 epidemics (peak incidence: 12.04‰ and 13.28‰, respectively). Both seasons were characterised by the introduction of novel viral strains: A/Fujian/411/2002(H3N2) (a drifted hemagglutinin variant) and A/California/7/2009(H1N1) pandemic virus (a swine origin quadruple reassortant), respectively. Because the antigenic match between vaccine and circulating strains was good in both of these seasons, a relevant proportion of cases may have been prevented by vaccination. A different situation was observed during the 2011-2012 season, when ILI morbidity rates in individuals ≥65-y-of-age were 1.5-6-fold higher than those registered during the other epidemics under review. The higher morbidity resulted from the circulation during the 2011-2012 season of an A/Victoria/361/2011(H3N2)-like variant that presented a reduced genetic match with the A(H3N2) strain included in the 2011-2012 vaccine composition. The continuous surveillance of the characteristics of circulating viruses is an essential tool for monitoring their matching with seasonal vaccine strains. Strategies to increase coverage rates are warranted.

Introduction: Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract illness in young children and can also cause influenza-like illness (ILI). Here we investigated the epidemiological features of RSV infection in pediatric ILI cases in Lombardy (a region in Northern Italy accounting nearly 10 million inhabitants) from 2014-2015 to 2020-2021 winter seasons.Material and Methods: Data for this study were retrieved and statistically analyzed from the database of virological influenza surveillance of the regional reference laboratory for Lombardy within the Italian influenza surveillance network (InfluNet).Results: RSV accounted for nearly 19% of pediatric ILI with a risk of infection nearly two-fold greater than that of individuals ≥15 years. RSV positivity rate increased to 28% considering 0-5 years old children. Although in children ≤5 years the risk of infection from influenza viruses resulted nearly two-fold higher than the risk of RSV infection, the age group 4-6 months and 7-12 months showed a five-fold greater risk of infection from RSV than from influenza. Children ≤5 years of age with preexisting underlying health conditions had a nearly five-fold greater risk of getting RSV infection than otherwise healthy 0-5 years old children. RSV was identified in ILI cases <15 years of age in all considered winter seasons except in the 2020-2021 season.Discussion: Sentinel surveillance of ILI allowed us to identify groups at higher risk of RSV and influenza infection and to define the start, duration, timing, and intensity of the RSV and influenza community circulation. This surveillance approach can be implemented to assess the RSV circulation and impact in a real-time manner.

This paper outlines the role of Lombardy’s regional influenza reference laboratory (Northern Italy) in the surveillance of influenza-like illnesses (ILIs) in monitoring SARS-CoV-2 circulation by analyzing 631 consecutive nasopharyngeal swabs (NPSs) collected from ILI outpatients by sentinel physicians during the 2019–2020 season. The samples were tested by specific real-time RT-PCRs targeting SARS-CoV-2, influenza viruses, and RSVs. Results: Of these NPSs, 31% tested positive for influenza viruses, 10% for SARS-CoV-2, and 7% for RSV. No coinfections were detected. Influenza viruses and RSVs circulated throughout the surveillance period until the end of February (week 9-2020), when they suddenly ceased to circulate seven weeks earlier than during the previous five influenza seasons. After the first detection of SARS-CoV-2 in our ILI outpatients at the beginning of March (week 10-2020), SARS-CoV-2 remained the only virus identified throughout the surveillance period. Patients ≥ 65 years had a 3.2-fold greater risk of being infected with SARS-CoV-2, while school-age children (5–14 years) and children < 5 years proved to be the age groups most at risk of contracting influenza viruses and RSV, respectively. Our experience demonstrates that laboratory-based ILI surveillance networks are essential for identifying SARS-CoV-2 cases that would otherwise remain undetected, in order to stop their spread within our communities.

Besides the influenza virus (IV), several other viruses are responsible for influenza-like illness (ILI). Although human parechoviruses (HPeVs) and enteroviruses (EVs) may impact on ILI, limited data on their epidemiological characteristics are available. During seven consecutive winter seasons (from 2010-2011 to 2016-2017), within the framework of an influenza surveillance system (InfluNet), 593 respiratory swabs were collected from children ≤5 years of age with ILIs. Molecular detection showed that 58.3 % of swabs were positive for at least one of the viruses under study: 46 % for IV, 13 % for EV and 5.4 % for HPeV. A single virus was identified in 51.3 % of samples while more than one virus was detected in 7 % of the samples. The risk of contracting IV was higher than the risk associated with EV, which in turn was higher than the risk of contracting HPeV. The risk of developing an IV infection was twofold greater in children >3 years than in those ≤3 years, who had higher risk of EV/HPeV infection. The frequency of EV/HPeV-positive swabs increased significantly during the 2016-2017 winter season compared to the previous six seasons. Sixteen EV genotypes were identified belonging to species A and B. HPeV-1 was the most frequently detected genotype, followed by -6 and -3. In this study, IV was mainly responsible for ILI, however EV and HPeV were also involved and particularly affected children ≤3 years of age. Influenza surveillance samples could provide us with valuable insight into the epidemiological features of viruses involved in ILI.

To compare the effectiveness of reverse transcription-polymerase chain reaction (RT-PCR), shell vial culture and cytospin assay as laboratory techniques for rapid diagnosis of influenza infections, a retrospective study was carried out on 270 aliquots of oropharyngeal swabs collected from October 1993 to March 1996 and already characterized by standard isolation procedures, and a prospective study in which 65 clinical samples taken from patients with influenza-like syndrome between October 1996 and March 1997 were tested. In the retrospective study, using conventional isolation as the gold standard, the sensitivity of RT-PCR and cytospin assay for virus A was 100% (95% confidence interval (CI), 89.1-100) and for virus B it was 100% (95% CI, 56.1-100) compared with 77.5% (95% CI, 61.1-88.6) and 71.4% (95% CI, 30.3-94.9) for shell vial culture. The specificity of all the three assays was 100% (95% CI, 98.0-100) for virus A and 100% (95% CI, 98.2-100) for virus B. In the prospective study the sensitivity of RT-PCR was greater than that of the other tests considered, both rapid and standard. It is suggested that RT-PCR should be employed in combination with conventional culture techniques in routine diagnosis of influenza infections in order to obtain results more rapidly and to improve virus detection even in circumstances in which standard isolation could be problematic.