Background: Influenza vaccine coverage rates are low, especially among low income, minority populations. Timely vaccination is important to ensure that young children and their contacts are protected before influenza begins to circulate. Traditional immunization reminders have had limited effectiveness in economically disadvantaged populations. Text messaging is a novel, scalable approach to promote influenza vaccination that has not yet been studied.
Objectives: To determine the efficacy of text message reminders for increasing timely influenza vaccination in an urban pediatric population.
Methods: We randomized n= 2,468 children 6-23 months old into intervention and control groups for the 2010-2011 influenza season. Children were patients in 4 community clinics associated with an academic medical center in an underserved community in New York City. Utilizing a registry-linked text messaging system, parents of intervention children received 5 weekly text messages, providing education about vaccine importance and notifying them of location and timing of influenza vaccine fairs. Messages were sent in October to mid November, and included child's first name and clinic name, and were sent in English or Spanish. Controls received standard of care: automated telephone reminders and fliers posted in the community clinics. Primary outcome was receipt of ≥1 influenza vaccine dose by November 30, assessed using Pearson's chi-square test. Logistic regression assessed the impact of race/ethnicity, insurance, and language.
Results: Nearly half (42%) of children were Latino; 87% had Medicaid. Using intention to treat analyses, 45.2% of intervention children vs. 38.8% (p=0.001) of controls received a dose by November 15. After controlling for variables that could affect influenza coverage, intervention children were still significantly more likely to receive a timely influenza vaccine dose (AOR 1.3; 95% CI 1.1, 1.5).
Conclusions: Immunization registry-linked text messaging was efficacious in promoting timely influenza vaccine delivery in a low income, urban, minority population. Funded by HRSA: R40MC17169