Vaccine
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Antibodies to measles, mumps, and rubella decline 3% per year on average, and have a high degree of individual variation. Yet, individual variations and differences across antigens are not well understood. To better understand potential implications on individual and population susceptibility, we reanalyzed longitudinal data to identify patterns of seropositivity and persistence. ⋯ The rate of antibody decay varied substantially among individuals and the 3 antigen groups. A fast rate of decline coupled with high variation was observed for mumps, yet no predictors were identified. Future research should focus on better understanding waning titers to mumps and its impacts on community protection and individual susceptibility, in light of recent outbreaks in vaccinated populations.
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Randomized Controlled Trial
Immunogenicity of a two-dose investigational hepatitis B vaccine, HBsAg-1018, using a toll-like receptor 9 agonist adjuvant compared with a licensed hepatitis B vaccine in adults.
Hepatitis B virus infection remains an important public health problem in the United States. Currently approved alum-adjuvanted vaccines require three doses and have reduced immunogenicity in adults, particularly in those who have diabetes mellitus, or are older, male, obese, or who smoke. ⋯ Two doses of HBsAg-1018, administered over 4 weeks, induced significantly higher seroprotection rates than three doses of HBsAg-Eng, given over 24 weeks, in adults with factors known to reduce the immune response to hepatitis B vaccines as well as in those without those factors. With fewer doses in a shorter time, and greater immunogenicity, HBsAg-1018 has the potential to significantly improve protection against hepatitis B in adults at risk for hepatitis B infection. Trial Registration clinicaltrials.gov Identifier: NCT02117934.
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Parental decision making about childhood vaccinations is complex and multidimensional. There is a perception that the number of parents having concerns regarding childhood vaccinations has been increasing in Canada. The aim of this study was to explore vaccine hesitancy among Canadian parents and to examine factors associated with a parent's intention to vaccinate his/her child. ⋯ Parents who had a high level of trust in doctors and public health were most likely to strongly intend to vaccinate their child. Results of the multivariate analysis showed that positive attitudes (aOR = 8.0; 95% CI: 6.0, 10.4), higher perceived social support (aOR = 3.0; 95% CI: 2.3, 3.93), and higher perceived behavioural control (aOR = 1.8; 95% CI: 1.4, 2.43) were associated with parents' intention to vaccinate their child. Findings of this study suggest that trust-building interventions that promote pro-vaccine social norms and that address negative attitudes toward vaccination could enhance vaccine acceptance among Canadian parents.
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The present study aimed to estimate residents' willingness to accept a future H7N9 vaccine and its determinants in the general adult population in Beijing, China. ⋯ A great number of Beijing residents had doubts about the vaccine's effectiveness and were not concerned about disease risk, which were the factors affecting willingness to be vaccinated. Targeted education programs on disease risk as well as vaccine's effectiveness are needed to improve the willingness of vaccination for potential H7N9 pandemic preparedness.
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Measles is a significant contributor to child mortality in the Democratic Republic of the Congo (DRC), despite routine immunization programs and supplementary immunization activities (SIA). Further, national immunization coverage levels may hide disparities among certain groups of children, making effective measles control even more challenging. This study describes measles vaccination coverage and reporting methods and identifies predictors of vaccination among children participating in the 2013-2014 DRC Demographic and Health Survey (DHS). ⋯ Results indicate that, while the overall coverage level of 70% is too low, socioeconomic and geographic disparities also exist which could make some children even less likely to be vaccinated. Dated records of measles vaccination must be increased, and groups of children with the greatest need should be targeted. As access to routine vaccination services is limited in DRC, identifying and targeting under-reached children should be a strategic means of increasing country-wide effective measles control.