Exclusion of pregnant people from emergency vaccine clinical trials: A systematic review of clinical trial protocols and reporting from 2009 to 2019.

BACKGROUND: Existing ethics guidance and regulatory requirements emphasize the need for pregnancy-specific safety and efficacy data during the development of vaccines in health emergencies. Our objective was to conduct a systematic review of vaccine clinical trials during active epidemic periods. METHODS: We searched for Phase II and Phase III vaccine clinical trials initiated during the H1N1 influenza, Middle East Respiratory Syndrome Coronavirus (MERS-CoV), Zika, and Ebola virus disease (EVD) outbreaks from 2009 to 2019. Data were extracted from clinical trial protocols identified in the following registries: ClinicalTrials.gov, Pan African Clinical Trial Registry (PACTR), and all primary registries indicated by the World Health Organization's International Clinical Trials Registry Platform (ICTRP). Published studies from registered clinical trials were located through PubMed. Data was extracted on eligibility criteria and pregnancy outcomes. Data from this study is available in the Center for Open Science Data Repository: https://osf.io/nfk2p/?view_only=47deb3b206724af9b46c9c0c0083a267. RESULTS: We identified 96 vaccine clinical trial protocols and included 84 in analysis. 5 records were excluded in screening for irrelevant abstracts, 7 were excluded in full-text assessment (1 for a therapeutic drug trial, 3 for enrolling elderly adults only, 3 for enrolling children/adolescents only). There were no eligible trials for MERS-CoV or Zika virus vaccines. Overall, 8 protocols explicitly included pregnant people; of these, 3 were completed trials with published results. Incidental pregnancies and outcomes of pregnant participants were reported in 2 studies, 10 studies reported serious adverse events related to pregnancy without mentioning total incidental pregnancies. A total of 411 recorded pregnancy outcomes were reported, with 293 from the 3 pregnancy-eligible studies with results. 71 serious adverse events pertaining to pregnancy were reported from all clinical trials with results. CONCLUSION: Pregnant people are underrepresented in vaccine clinical trials conducted during outbreaks, resulting in underreporting of pregnancy-related outcomes and a lack of protection for pregnant people and neonates from infectious diseases.

Social media strategies to affect vaccine acceptance: a systematic literature review.

Introduction: Vaccine hesitancy, defined as a delay in the acceptance or the refusal of vaccines despite their availability, is a growing global threat. More individuals are turning to social media for health information, including vaccine information. As such, there is an opportunity to leverage online platforms as a means to disseminate and persuade individuals toward vaccine acceptance. We sought to review literature focused on the influence of exposure to social media content on vaccine acceptance or hesitancy.Areas covered: This review focused on social networking sites (e.g. Facebook) and content communities (e.g. YouTube), to understand how exposure to vaccine information affected vaccine knowledge, attitudes, and intentions/behaviors. We searched PubMed, CINAHL, Scopus, and Inspec. We included English-language materials published from 2004 to 2020 and included interventional studies, observational studies, and impacts of policies. We excluded systematic reviews, protocols, editorials, letters, case reports, case studies, commentaries, opinion pieces, narrative reviews, and clinical guidelines.Expert opinion: Social media interventions to affect vaccine acceptance is a new but growing area of study. How a communication message is framed, who delivers the message, and network structure are critical for affecting the vaccine decision-making process. Social media should be leveraged to impact vaccine uptake.