Molecular and serological diversity of Neisseria meningitidis carrier strains isolated from Italian students aged 14 to 22 years.

Neisseria meningitidis is an obligate human commensal that commonly colonizes the oropharyngeal mucosa. Carriage is age dependent and very common in young adults. The relationships between carriage and invasive disease are not completely understood. In this work, we performed a longitudinal carrier study in adolescents and young adults (173 subjects). Overall, 32 subjects (18.5%) had results that were positive for meningococcal carriage in at least one visit (average monthly carriage rate, 12.1%). Only five subjects tested positive at all four visits. All meningococcal isolates were characterized by molecular and serological techniques. Multilocus sequence typing, PorA typing, and sequencing of the 4CMenB vaccine antigens were used to assess strain diversity. The majority of positive subjects were colonized by capsule null (34.4%) and capsular group B strains (28.1%), accounting for 23.5% and 29.4% of the total number of isolates, respectively. The fHbp and nhba genes were present in all isolates, while the nadA gene was present in 5% of the isolates. The genetic variability of the 4CMenB vaccine antigens in this collection was relatively high compared with that of other disease-causing strain panels. Indications about the persistence of the carriage state were limited to the time span of the study. All strains isolated from the same subject were identical or cumulated minor changes over time. The expression levels and antigenicities of the 4CMenB vaccine antigens in each strain were analyzed by the meningococcal antigen typing system (MATS), which revealed that expression can change over time in the same individual. Future analysis of antigen variability and expression in carrier strains after the introduction of the MenB vaccine will allow for a definition of its impact on nasopharyngeal/oropharyngeal carriage.

Human Papillomavirus Vaccine: State of the Art and Future Perspectives.

Human Papillomavirus (HPV) is a widely distributed and common virus, that causes benign lesions (such as warts and papillomas) but, if not cleared, can lead to malignant lesions as well, such as intraepithelial lesions and neoplasia. An extensive body of researches has demonstrated that E1 and E2 are involved in viral transcription and replication, E5, E6, and E7 act as oncoproteins, whilst L1 and L2 contribute to the formation of the capsid. However, this view has been recently challenged, since also E2 could play a role in HPV-induced carcinogenesis. Therefore, a complex picture is emerging, opening new ways and perspectives. The present article provides an overview of the biology of HPV, paying particular attention to its structural details and molecular mechanisms. The article also shows how this knowledge has been exploited for developing effective vaccines, both prophilactic/preventive and therapeutic ones. L1-based prophylactic vaccines, like Gardasil, Cervarix, and Gardasil 9, have been already licensed, whilst L2-based second generation preventive vaccines are still under clinical trials. New, highly immunogenic and effective vaccines can be further developed thanks to computer-aided design and bioinformatics/computational biology. The optimization of combinational therapies is another promising opportunity.

Evaluation of the economic burden of Herpes Zoster (HZ) infection.

The main objective of this systematic review was to evaluate the economic burden of Herpes Zoster (HZ) infection.   The review was conducted in accordance with the standards of the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" guidelines. The following databases were accessed: ISI/Web of Knowledge (WoS), MEDLINE/PubMed, Scopus, ProQuest, the Cochrane Library and EconLit. Specific literature on health economics was also manually inspected. Thirty-three studies were included. The quality of the studies assessed in accordance with the Consolidated Health Economic Evaluation Reporting Standards checklist was good. All studies evaluated direct costs, apart from one which dealt only with indirect costs. Indirect costs were evaluated by 12 studies. The economic burden of HZ has increased over time. HZ management and drug prescriptions generate the highest direct costs. While increasing age, co-morbidities and drug treatment were found to predict higher direct costs, being employed was correlated with higher indirect costs, and thus with the onset age of the disease. Despite some differences among the selected studies, particularly with regard to indirect costs, all concur that HZ is a widespread disease which has a heavy social and economic burden.