Objective: Since states' public health systems differ as to pandemic preparedness, this study explored whether such heterogeneity among states could affect the nation's overall influenza rate.
Design: The Centers for Disease Control and Prevention produced a uniform set of scores on a 100-point scale from its 2008 national evaluation of state preparedness to distribute materiel from the Strategic National Stockpile (SNS). This study used these SNS scores to represent each state's relative preparedness to distribute influenza vaccine in a timely manner and assumed that “optimal” vaccine distribution would reach at least 35% of the state's population within 4 weeks. The scores were used to determine the timing of vaccine distribution for each state: each 10-point decrement of score below 90 added an additional delay increment to the distribution time.
Setting and Participants: A large-scale agent-based computational model simulated an influenza pandemic in the US population. In this synthetic population each individual or agent had an assigned household, age, workplace or school destination, daily commute, and domestic intercity air travel patterns.
Main Outcome Measures: Simulations compared influenza case rates both nationally and at the state level under 3 scenarios: no vaccine distribution (baseline), optimal vaccine distribution in all states, and vaccine distribution time modified according to state-specific SNS score.
Results: Between optimal and SNS-modified scenarios, attack rates rose not only in low-scoring states but also in high-scoring states, demonstrating an interstate spread of infections. Influenza rates were sensitive to variation of the SNS-modified scenario (delay increments of 1 day versus 5 days), but the interstate effect remained.
Conclusions: The effectiveness of a response activity such as vaccine distribution could benefit from national standards and preparedness funding allocated in part to minimize interstate disparities.
Since states' public health systems differ as to pandemic preparedness, this study explored whether such heterogeneity among states could affect the nation's overall influenza rate.
Graduate School of Public Health, University of Pittsburgh (Drs Potter, Brown, Lee, Grefenstette, Keane, Lin, Quinn, Stebbins, Sweeney, and Burke), Pittsburgh Supercomputing Center (Dr Brown), and School of Medicine, University of Pittsburgh (Drs Lee and Lin), Pittsburgh, Pennsylvania.
Correspondence: Margaret A. Potter, Center for Public Health Practice, Graduate School of Public Health, 130 DeSoto St, Pittsburgh, PA 15261 (firstname.lastname@example.org).
This work was supported by the Preparedness and Emergency Response Research Centers of the Centers for Disease Control and Prevention, Cooperative Agreement Number 1P01TP000304. The contents of this report are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention. Additional support came from the MIDAS grant 1U54GM088491-01 of the National Institute of General Medical Sciences, which had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
The authors thank the members of our research team who assisted with this work: Sherrianne M. Gleason, PhD; Tina Batra Hershey, JD, MPH; and Xiaozhi Zhou, MS.
The authors report no conflicts of interest.