Vaccine shot-limiting: Estimating the prevalence, indicators, and impact on vaccination status — Michigan, 2012

Vaccine
Volume 35, Issue 7, Pages 993-1100 (15 February 2017)
http://www.sciencedirect.com/science/journal/0264410X/35/7

Vaccine shot-limiting: Estimating the prevalence, indicators, and impact on vaccination status — Michigan, 2012
Original Research Article
Pages 1018-1023
Meghan Weinberg, Stephanie Dietz, Rachel Potter, Robert Swanson, Corinne Miller, Jevon McFadden
Abstract
Background
Concerns regarding vaccine safety and pain have prompted certain parents to limit the number of shots their child receives per visit. We estimated the prevalence of shot-limited children in Michigan, described their characteristics, assessed whether shot-limited children were up-to-date on recommended vaccinations, and investigated possible intervention points for vaccination education.
Methods
We analyzed vaccination registry and birth record data of children born in Michigan during 2012 who had ⩾2 vaccination visits, with ⩾1 visits after age 5 months. Shot-limited was defined as receiving ⩽2 shots at all visits through age 24 months. Nonlimited children received >2 shots at ⩾1 visits. Up-to-date vaccination was based on receipt of a seven-vaccine series and was determined at ages 24 months and 35 months. Risk ratios (RR) were calculated using risk regression.
Results
Of 101,443 children, a total of 2,967 (3%) children were shot-limited. Mothers of shot-limited children were more likely to be white (RR: 1.2; 95% confidence interval [CI]: 1.2–1.2), college graduate (RR: 1.9; 95% CI: 1.9–2.0), and married (RR: 1.5; 95% CI: 1.5–1.5). Compared with nonlimited children, shot-limited children were more likely to be born in a nonhospital setting (RR: 11.7; 95% CI: 9.4–14.6) and have a midwife attendant (RR: 1.9; 95% CI: 1.7–2.1). Shot-limited children were less likely to be up-to-date on recommended vaccinations (RR: 0.2; 95% CI: 0.2–0.3); this association was stronger for those with a midwife birth attendant (RR: 0.1; 95% CI: 0.1–0.2) rather than a medical doctor (RR: 0.3; 95% CI: 0.2–0.3).
Conclusions
Shot-limited children are less likely to be up-to-date on vaccinations, possibly leading to increased risk for vaccine-preventable diseases. This association was stronger for those with a midwife birth attendant. This analysis should prompt targeted education, such as to midwives, concerning risks associated with shot-limiting behavior.