Improving influenza and tetanus, diphtheria and acellular pertussis
(Tdap) vaccination among pregnant women in Georgia
Abramson, Allison Chamberlain
Dissertation (207 pages)
Committee Chair / Thesis Adviser: Omer, Saad B
Committee Members: Berkelman, Ruth L ; Orenstein, Walter ; Rosenberg, Eli S ; Ault, Kevin
Research Fields: Health Sciences, Epidemiology
Keywords: vaccination; antenatal; influenza; Tdap; randomized trial
Program: Laney Graduate School, Epidemiology
Influenza and pertussis are two diseases which pose danger to pregnant women and newborns. Pregnant women are at increased risk for complications from influenza, and infants less than 2 months old have the greatest risk of mortality from pertussis. Vaccination during pregnancy (i.e. antenatal vaccination), is a safe and effective strategy to protect mothers and infants. Despite risks posed by these diseases and the protective benefits afforded by vaccination, antenatal vaccination rates against seasonal influenza and pertussis are suboptimal.
Considerable research has sought to understand why pregnant women remain unvaccinated. Reasons include safety concerns, perceptions of low disease susceptibility, inadequate knowledge of vaccination, and no provider recommendation. Barriers also exist for obstetric providers. Despite awareness of these barriers, little research has scientifically evaluated evidence-based interventions to improve vaccination rates.
In dissertation aim 1, we conducted the MOMVAX Study, a cluster-randomized trial among 325 pregnant women in 11 obstetric practices in Georgia from 2012-2013 to test the effectiveness of a comprehensive multi-component intervention package on increasing likelihood of antenatal influenza and/or Tdap receipt. While vaccination rates were higher in the intervention group compared to the control group, differences were not significant.
In aim 2, we examined the effectiveness of the MOMVAX intervention package on improving knowledge, attitudes and beliefs about antenatal vaccination. While we observed no overall effects of exposure to the package, we found that women enrolled in their third trimester were more likely to have requested family members to get vaccinated to protect the infant if they were in the intervention group versus the control group.
In aim 3, using 8 years of data from the Georgia Pregnancy Risk Assessment Monitoring System, we explored trends in reasons for non-receipt of antenatal influenza vaccination from 2004-2011. We found that while the prevalence of citing certain reasons decreased over time, safety concerns increased significantly following the 2009/2010 H1N1 influenza pandemic, and especially among Hispanic women.
Through the first experimental evaluation of a multi-component intervention package to improve antenatal vaccination and the analysis of trends in reasons for non-receipt, this dissertation contributes to the development of evidence-based interventions to improve antenatal vaccination.
Table of Contents
CHAPTER 1: OVERVIEW AND MOTIVATION 1
CHAPTER 2: BACKGROUND AND LITERATURE REVIEW 5
CHAPTER 3: MOMVAX STUDY DESIGN AND INTERVENTION 26
CHAPTER 4: PRELIMINARY MANUSCRIPT 29
CHAPTER 5: MANUSCRIPT 1 47
CHAPTER 6: MANUSCRIPT 2 73
CHAPTER 7: MANUSCRIPT 3 95
CHAPTER 8: CONCLUSIONS AND FUTURE DIRECTIONS 117
Appendix A: A priori rules for determining influenza and Tdap vaccination status in Emory MOMVAX study 124
Appendix B: MOMVAX study baseline questionnaire 126
Appendix C: MOMVAX study post-partum follow-up questionnaire 131
Appendix D: MOMVAX intervention package components 150