Can a patient diagnosed with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) be infected again? This question is still unsolved. We tried to analyze local and literature cases with a positive respiratory swab after recovery. We collected data from symptomatic patients diagnosed with SARS-CoV-2 infection in the Italian Umbria Region that, after recovery, were again positive for SARS-CoV-2 in respiratory tract specimens. Samples were also assessed for infectivity in vitro. A systematic review of similar cases reported in the literature was performed. The study population was composed of 9 patients during a 4-month study period. Among the new positive samples, six were inoculated in Vero-E6 cells and showed no growth and negative molecular test in culture supernatants. All patients were positive for IgG against SARS-CoV-2 nucleoprotein and/or S protein. Conducting a review of the literature, 1350 similar cases have been found. The presumptive reactivation occurred in 34.5 days on average (standard deviation, SD, 18.7 days) after COVID-19 onset, when the 5.6% of patients presented fever and the 27.6% symptoms. The outcome was favorable in 96.7% of patients, while the 1.1% of them were still hospitalized at the time of data collection and the 2.1% died. Several hypotheses have been formulated to explain new positive respiratory samples after confirmed negativity. According to this study, the phenomenon seems to be due to the prolonged detection of SARS-CoV-2 RNA traces in respiratory samples of recovered patients. The failure of the virus to replicate in vitro suggests its inability to replicate in vivo.

Bacterial vaginosis (BV) is characterized by the presence of a polymicrobial biofilm where Gardnerella vaginalis plays a key role. Previously, we demonstrated that Saccharomyces cerevisiae CNCM (French National Collection of Cultures of Microorganisms) I-3856 is helpful in resolving experimental simulated BV in mice. In this study, we analyzed its capacity to affect G. vaginalis biofilms and to potentiate the activity of standard antimicrobial agents. We also investigated the anti-biofilm activity of Lacticaseibacillus rhamnosus GG (ATCC 53103), a well-known strain for its intestinal healthy benefits. Biofilm biomass was assessed by crystal violet staining, and G. vaginalis viability was assessed by a colony forming unit (CFU) assay. Here, for the first time, we demonstrated that S. cerevisiae CNCM I-3856 as well as L. rhamnosus GG were able (i) to significantly inhibit G. vaginalis biofilm formation, (ii) to markedly reduce G. vaginalis viability among the biomass constituting the biofilm, (iii) to induce disaggregation of preformed biofilm, and (iv) to kill a consistent amount of bacterial cells in a G. vaginalis preformed biofilm. Furthermore, S. cerevisiae CNCM I-3856 strongly potentiates the metronidazole effect on G. vaginalis biofilm viability. These results suggest that S. cerevisiae CNCM I-3856 as well as L. rhamnosus GG could be potential novel therapeutic agents against bacterial vaginosis.

The age-related weakening of the immune system makes elderly subjects less responsive to influenza vaccination. In the last years, two “enhanced vaccines” were licensed for individuals aged ≥65 years, one being a subunit vaccine (Fluad®) containing the MF59 adjuvant administered intramuscularly (IM-MF59) and the other one a split non-adjuvanted vaccine administered intradermally (Intanza® 15mcg) (ID). In the present study, we evaluated and compared the antibody responses against the three vaccine antigens and heterovariant A(H3N2) circulating viruses induced by IM-MF59 and ID influenza vaccines in 80 elderly institutionalized volunteers (40 per group) during the Winter season 2011–2012.

Acute gastroenteritis (AGE) due to group A rotavirus (RVA) agent is one of the major causes of hospitalization in paediatric age. The G3P[8] RVA genotype has been usually considered as one of the major human genotypes, largely circulating in Asia, but showing low detection rates in the European countries. In recent years, the G3P[8] RVAs emerged also in Europe as a predominant genotype and the viral strains detected revealed high similarities with equine-like G3P[8] RVA strains, resulting in a new variant circulating in humans and able to cause AGE in the paediatric population. An 8-year-old boy was admitted to the Emergency Room because he had suffered from severe diarrhoea, vomiting, and high fever over the previous two days. Severe dehydration was evident based on low serum concentrations of potassium and sodium, low glycaemia, and pre-renal failure (creatinine 2.48 mg/dL, urea 133 mg/dL). Immunological tests were within normal range. Enzyme immunoassay for the detection of RV was positive, and a sample of faeces was collected in order to perform the molecular characterization of the viral strain. The phylogenetic trees revealed relatedness between the VP7 and VP4 genes of the G3P[8] RVA Italian strain (namely PG2) and those belonging to recent G3P[8] RVAs detected worldwide. The G3 VP7 belonged to the G3-I lineage and shared the highest nucleotide sequence identity (99.8%) with the equine-like G3 previously identified in other countries. The P [8] VP4 revealed a similar clustering pattern to that observed for the VP7. In addition, the molecular characterization of the 11 gene segments of strain PG2 revealed a G3-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2 genomic constellation. This case shows the first detection in Italy of a reassortant G3P[8] RVA associated with a severe AGE, which is unusual in a school-age child without any known severe underlying problems. The findings reported in this paper highlight the importance of continuously monitoring the RVA strains circulating in paediatric age in order to detect novel viral variants able to spread in the general population.

Acute respiratory infections (ARIs) are extremely common in children, especially those under 5 years old. They can lead to complications, super-infection, respiratory failure, and even compromised respiratory function in adulthood. For some of the responsible pathogens, vaccines are available. This review reports current issues about vaccines against the main respiratory pathogens to highlight the available strategies to reduce the burden of paediatric respiratory disease. The optimal use of influenza, pneumococcal, pertussis and measles vaccines is required in order to reduce ARI burden. Vaccination coverage rates must be improved to achieve the full benefits of these vaccines. Recently, advances in the knowledge of respiratory syncytial virus structural biology and immunology as well as the development of new techniques to generate vaccine candidates have increased the number of promising vaccines even against this harmful pathogen.

Influenza vaccination is considered the best mean for preventing the higher rates of mortality associated with influenza virus infection in the elderly as compared with younger people. Since the number of very elderly subjects, aged >85 years, is rapidly increasing, and some authors reported increments in influenza-associated mortality with age, the aim of this study was to increase the limited information available on the immunogenicity of the influenza vaccines in this age group. This was a retrospective study which analyzed the antibody response induced by commercially available trivalent inactivated influenza vaccines in 1491 elderly subjects (60–85 years old) and 1139 very elderly subjects (>85 years old) during 21 winter seasons included between 1993–1994 and 2014–2015. The antibody response of the two age groups was, in most instances, acceptable according to the Committee for Medical Products for Human Use and comparable. In accordance with previous data obtained in the elderly, the use of MF59-adjuvanted or intradermal administered vaccines (enhanced vaccines) was found to be preferable as compared with conventional formulations (split or subunit vaccines). Vaccines containing new strains induced higher antibody response as compared with vaccines with the same antigenic composition of the previous years. These results suggest that the current recommendation for use of enhanced influenza vaccines for the elderly is appropriate, but that efforts to improve the effectiveness of the present prophylactic measures against influenza are needed, especially in the years with vaccines with the same antigenic composition of the previous winter season.