Knowledge of interim recommendations and use of Hib vaccine during vaccine shortages

Abstract

Objectives: The goals were to determine among pediatricians and family physicians (1) knowledge of interim recommendations regarding Haemophilus influenzae type b (Hib) vaccine administration, (2) current practices, and (3) factors associated with nonadherence.

Methods: An Internet-based survey was conducted in April 2008 among national samples.

Results: Response rates were 68% (220 of 325 physicians) among pediatricians and 51% (153 of 302 physicians) among family physicians. Seventy-three percent of pediatricians and 45% of family medicine physicians reported insufficient Hib vaccine supplies, and 22% to 24% reported having to defer doses for infants 2 to 6 months of age > or =10% of the time. Ninety-eight percent of pediatricians and 81% of family physicians were aware of the interim recommendations (P < or = .0001), and virtually all knew that the booster dose should be deferred; however, 22% of pediatricians and 33% of family medicine physicians reported not deferring this dose. Physicians in both specialties were less likely to adhere to recommendations to defer in this age group if they thought that their practice had sufficient vaccine supplies (pediatricians, odds ratio: 0.01 [95% confidence interval: 0.003-0.03]; family medicine physicians, odds ratio: 0.10 [95% confidence interval: 0.03-0.33]). Family medicine physicians were less likely to adhere to recommendations if they had not heard about the interim recommendations (odds ratio: 0.04 [95% confidence interval: 0.01-0.21]).

Conclusions: Most primary care physicians experienced Hib vaccine shortages, and many have had to defer doses for 2- to 6-month-old children. Most are knowledgeable regarding interim recommendations, but one-fifth to one-third reported nonadherence.