Characteristics of YouTube videos about the meningococcal B vaccine (4CMenB)

YouTube has become a large source of health information, and it has the capacity to influence users: for instance, regarding their vaccination habits. The aim of our study was to analyze the characteristics of the videos published on YouTube about the meningococcal B vaccine (4CMenB, Bexsero®). A search was made on YouTube using the keyword "Bexsero." The association between the authorship of videos (health professionals or others) and the rest of the variables (tone of the message and vaccination recommendations, among others) was evaluated using the Chi-square test. In total, 77 videos were analyzed; 74% supported the use of the vaccine, and the most frequently mentioned vaccination recommendations were in epidemic outbreaks (28.6%) and in children (18.2%). Depending on the type of authorship, significant differences were observed regarding the tone of the message and the frequency with which the videos discussed effectiveness, dosage, adverse effects, and vaccination recommendations. There is a difficulty in obtaining information on vaccination recommendations. Recommendations are very diverse since there is a great heterogeneity in the official recommendations for the use of this vaccine, depending on the country the information is from.

Understanding Factors Affecting University A Students' Decision to Receive an Unlicensed Serogroup B Meningococcal Vaccine

PURPOSE

During March-November 2013, five cases of serogroup B meningococcal disease occurred among University A undergraduates. The Centers for Disease Control and Prevention used the unlicensed MenB-4C (Bexsero, Novartis Vaccines), a serogroup B meningococcal vaccine, to control the outbreak. All undergraduates (n = 19,257) were offered two doses; 51% of undergraduates received ≥1 dose of MenB-4C. We conducted a knowledge, attitudes, and practice survey to understand which factors and sources of information impacted their decision on whether or not to receive vaccine.

METHODS

An anonymous online survey was sent to University A undergraduates. The survey was implemented in June 2-30, 2014, and covered demographics, MenB-4C vaccination decision, and sources of information. Descriptive analyses were conducted.

RESULTS

A total of 1,341 students completed the survey (response rate = 7.0%), of these 873 received ≥1 dose of MenB-4C. Among vaccinated respondents, the predominant reasons for receiving vaccine were knowledge of disease severity, parental recommendation, and believing that vaccination offered the best protection. Among unvaccinated respondents, the predominant reasons for not receiving vaccine were perception of low disease risk and concern over vaccine newness and safety. Respondents' top primary sources of information were e-mails from the university followed by their parents.

CONCLUSIONS

Reasons behind respondents' decision to receive an unlicensed vaccine were similar to those reported for routinely recommended vaccines. Given the challenges around communicating the importance of receiving a vaccine that is not routinely recommended, respondents' primary sources of information, the university and their parents, could be targeted to improve coverage rates.

Immune responses to a recombinant, four-component, meningococcal serogroup B vaccine (4CMenB) in adolescents: a phase III, randomized, multicentre, lot-to-lot consistency study

BACKGROUND

For decades, a broadly effective vaccine against serogroup B Neisseria meningitidis (MenB) has remained elusive. Recently, a four-component recombinant vaccine (4CMenB) has been developed and is now approved in Europe, Canada, Australia and some Latin American countries. This phase III, randomized study evaluated the lot consistency, early immune responses and the safety profile of 4CMenB in 11 to 17-year-old adolescents in Australia and Canada (NCT01423084).

METHODS

In total, 344 adolescents received two doses of one of 2 lots of 4CMenB, 1-month apart. Immunogenicity was assessed before, 2-weeks and 1-month following the second vaccination. Serum bactericidal activity using human complement (hSBA) was measured against three reference strains 44/76-SL, 5/99 and NZ98/254, selected to express one of the vaccine antigens; Neisseria adhesin A (NadA), factor H binding protein (fHbp) and porin A (PorA) containing outer membrane vesicle (OMV), respectively. Responses to the Neisseria heparin binding antigen (NHBA) were assessed with enzyme linked immunosorbent assay (ELISA). Local and systemic reactions were recorded for 7 days following each vaccination; unsolicited adverse events were monitored throughout the study.

RESULTS

Immunological equivalence of the two lots of 4CMenB was established at 1-month. At baseline, ≤7% of participants had hSBA titers ≥5 to all three reference strains. Two weeks following the second dose of 4CMenB, all participants had hSBA titers ≥5 against fHbp and NadA compared with 84-96% against the PorA reference strains. At 1-month, corresponding proportions were 99%, 100% and 70-79%, respectively. Both lots were generally well tolerated and had similar adverse event profiles.

CONCLUSIONS

Two doses of 4CMenB had an acceptable safety profile and induced a robust immune response in adolescents. Peak antibody responses were observed at 14 days following vaccination. While a substantial non-uniform antigen-dependent early decline in antibody titers was seen thereafter, a significant percentage of participants continued to maintain protective hSBA titers at 1-month.