Development of a US trust measure to assess and monitor parental confidence in the vaccine system.

OBJECTIVE: To develop a Vaccine Confidence Index (VCI) that is capable of detecting variations in parental confidence towards childhood immunizations centered on trust and concern issues that impact vaccine confidence. METHODS: We used a web-based national poll of 893 parents of children <7 years in 2016 to assess the measures created for the Emory VCI (EVCI). EVCI measures were developed using constructs related to vaccine confidence identified by the U.S. National Vaccine Advisory Committee (i.e., "Information Environment", "Trust", "Healthcare Provider", "Attitudes and Beliefs", and "Social Norms"). Reliability for EVCI was assessed using Cronbach's alpha. Using the variables related to each of the constructs, we calculated an overall EVCI score that was then assessed against self-reported childhood vaccine receipt using chi-square and the Cochrane-Armitage trend tests. RESULTS: Respondents' EVCI scores could range from 0 to 24, and the full range of values was observed in this sample (Mean = 17.5 (SD 4.8)). EVCI scores were significantly different (p ≤ 0.006 for all comparisons) between parents who indicated their child(ren) received routinely recommended vaccines compared with parents who indicated they had delayed or declined recommended immunizations. There was also a significant, consistent association between higher EVCI scores and greater reported vaccine receipt. CONCLUSIONS: We developed EVCI to reliably measure parental vaccine confidence, with individuals' scores linked to parental vaccine-related attitudes, intentions, and behaviors. As such, EVCI may be a useful tool for future monitoring of both population and individual confidence in childhood immunization.

Development of a measure to assess vaccine confidence among men who have sex with men.

BACKGROUND: Recent serogroup C meningococcal disease outbreaks led to meningococcal vaccine recommendations for Southern California men who have sex with men (MSM). Assessment of vaccine confidence is critical to improving vaccine coverage in the context of disease outbreaks wherein immunization(s) are recommended. METHODS: We surveyed MSM using venue-based sampling and began development of the vaccine confidence index (VCI) with 30 survey items corresponding to trust- and safety-related perceptions. We performed exploratory factor analyses and computed the Cronbach's alpha coefficient to assess internal consistency of the VCI. We created a categorical confidence variable (low, medium, and high confidence) and conducted bivariate and multivariate analyses to evaluate associations with reported confidence and immunization uptake. RESULTS: Ten survey items were included in the final VCI and formed the confidence measure. Participants with low confidence had the lowest levels of reported uptake for both meningococcal vaccines. Confidence differed significantly (p ≤ 0.05) between MSM who indicated they received vaccines recommended within the context of the outbreak and those who did not. CONCLUSIONS: Our VCI is sensitive to a number of issues that may influence vaccine confidence. It is useful for assessing MSM trust and acceptance of recommended immunizations and may be used to inform intervention development.

Quadrivalent Meningococcal Vaccine Uptake Among Men Who Have Sex With Men During a Meningococcal Outbreak in Los Angeles County, California, 2016-2017.

OBJECTIVE: The objective of our study was to assess meningococcal ACWY (MenACWY) vaccine uptake among men who have sex with men (MSM) during an ongoing, invasive meningococcal disease outbreak in Southern California. This research was important to inform future vaccination uptake interventions for this high-priority population. METHODS: We conducted venue-based sampling to recruit and enroll MSM living in Los Angeles County, California, from December 2016 through February 2017. We conducted bivariate and multivariable analyses to evaluate associations between MenACWY vaccine uptake and other predetermined factors. RESULTS: Of 368 participants, 138 (37.5%) reported receiving the MenACWY vaccine. In multivariable analyses, older age (adjusted odds ratio [aOR] = 2.57; 95% confidence interval [CI], 1.31-5.03), previous diagnosis of a sexually transmitted infection (aOR = 2.22; 95% CI, 1.14-4.30), belief that MenACWY vaccine is important (aOR = 3.49; 95% CI, 1.79-6.82), confidence in the MenACWY vaccine (aOR = 5.53; 95% CI, 3.11-9.83), and knowing someone who had been vaccinated (aOR = 5.82; 95% CI, 3.05-11.12) were significantly associated with MenACWY vaccine uptake. CONCLUSIONS: Our findings reflect low uptake of the recommended MenACWY vaccine among MSM after a local outbreak, despite public health efforts. In addition to ongoing, widespread campaigns to inform MSM about local outbreaks and vaccination recommendations, MSM may be responsive to direct outreach from peers who have been vaccinated.

Factors Associated with Immunization Opinion Leadership among Men Who Have Sex with Men in Los Angeles, California.

We sought to identify the characteristics of men who have sex with men (MSM) who are opinion leaders on immunization issues and to identify potential opportunities to leverage their influence for vaccine promotion within MSM communities. Using venue-based sampling, we recruited and enrolled MSM living in Los Angeles (N = 520) from December 2016 to February 2017 and evaluated characteristic differences in sociodemographic characteristics, health behaviors, and technology use among those classified as opinion leaders versus those who were not. We also asked respondents about their past receipt of meningococcal serogroups A, C, W, and Y (MenACWY) and meningococcal B (MenB) vaccines, as well as their opinions on the importance of 13 additional vaccines. Multivariable results revealed that non-Hispanic black (aOR = 2.64; 95% CI: 1.17⁻5.95) and other race/ethnicity (aOR = 2.98; 95% CI: 1.41⁻6.29) respondents, as well as those with a history of an STI other than HIV (aOR = 1.95; 95% CI: 1.10⁻3.48), were more likely to be opinion leaders. MenACWY (aOR = 1.92; 95% CI: 1.13⁻3.25) and MenB (aOR = 3.09; 95% CI: 1.77⁻5.41) vaccine uptake, and perceived importance for these and seven additional vaccines, were also associated with being an opinion leader. The results suggest that the co-promotion of vaccination and other health promotion initiatives via opinion leaders could be a useful strategy for increasing vaccination among MSM.