Shortage of influenza vaccine in 2000–2001: Did it change patient beliefs?

doi:10.1016/S0749-3797(03)00018-7

American Journal of Preventive Medicine

Volume 24, Issue 4, May 2003, Pages 349-353

https://doi.org/10.1016/S0749-3797(03)00018-7 Get rights and content

Abstract

Objectives

To determine which patient beliefs associated with influenza vaccination changed during a vaccine shortage year (2000–2001) from a nonshortage year (1999–2000).

Methods

Elderly patients (n=319), who had been previously interviewed about the 1999–2000 influenza season, were interviewed regarding the 2000–2001 season. Participants were from inner-city and suburban medical practices receiving influenza vaccine supply on time or late in the season.

Results

Although vaccination rates did not diminish due to the influenza vaccine shortage (73% in 1999–2000 vs 74% in 2000–2001), some patient attitudes changed. More respondents expressed concerns about the influenza vaccine (3% in 1999–2000 vs 12% in 2000–2001, p<0.0001), and fewer responded that friends thought that they should get the vaccine (75% 1999–2000 vs 66% 2000–2001, p=0.005); that if one person in the household “got the flu” others would also (71% 1999–2000 vs 67% 2000–2001, p<0.0001), and that “a person who does not get the flu shot will get influenza” (36% 1999–2000 vs 30% 2000–2001, p=0.02).

Conclusions

The influenza vaccine shortage resulted in a small increase in concerns about influenza vaccine, even in a population with good access to vaccine and high vaccination rates. Vaccine availability updates should include reassurances of vaccine safety and efficacy.

Introduction

D uring the influenza vaccination season of 2000–2001, there was an unprecedented, widespread, and highly publicized delay in distribution of influenza vaccine. By the end of October 2000, only 26.6 million doses (38% of the total) had been distributed, compared with 75.8 million doses (99% of the total) by the end of October 1999.1 This delay was due to difficulties encountered by some manufacturers in growing the H3N2 strain, regulatory issues related to the Food and Drug Administration’s good manufacturing practices, and the decision by one manufacturer to permanently cease influenza vaccine production.1 Depending on their vaccine source(s), providers may have received their supplies up to 3 months later than usual, in reduced amounts, and frequently at higher cost than in previous years. Younger healthy people were asked to delay getting the influenza vaccine to ensure that older and high-risk individuals had the first opportunity to receive the vaccine while supplies were limited.2 However, distribution was uneven: providers serving primarily older and high-risk populations frequently did not receive vaccine, while employers and others serving low-risk populations did.1 These distribution patterns may have changed how influenza disease and vaccine were perceived by individuals who should have received vaccine first.

This study examined changes in patient perceptions of the influenza vaccine during the 2000–2001 influenza season in a population that was surveyed the previous year.

Section snippets

Subjects

Following the 1999–2000 influenza season, a telephone survey of older patients was conducted. Participants were selected using a two-stage stratified random cluster sample3, 4, 5 regarding attitudes and beliefs about influenza vaccine and disease. For the present study, all patients were selected from the previous study sample and from four inner-city practices (three of which received influenza vaccine on time and one that received it late, in December) as well as from a random sample of

Response rate

Among the 387 sampled patients, 25 were found to be ineligible, 43 refused or could not be contacted, and 319 agreed to participate in the second interview—for a response rate of 82% (319/387).

Demographics

Demographic characteristics of the study sample are shown in Table 1. This population was predominantly female, of white race, widowed, of lower educational level, and of low to moderate household income. Differences occurred among the practice location/timing groups for age (p<0.01); gender (p<0.01);

Discussion

What was the impact of the delay in influenza vaccine distribution for 2000–2001? We offer three consequences that were modest in degree: (1) decreased vaccination rates; (2) increased patient concerns about vaccine safety; and (3) increased patient concerns about vaccine efficacy. The production difficulties encountered in 2000 resulted in a significant delay in distribution and reduction in vaccine supplies. Of the 70.4 million doses made in 2000 (down from 77.9 million doses in 19991), 7.5

Conclusions

The ever-present possibility of pandemic influenza and the withdrawal of two manufacturers from the inactivated influenza vaccine market highlight the fact that shortages could occur in the future. Small increases in concerns about vaccines during a vaccine shortage, even among adults with good access to vaccine supplies, suggest the need for clear messages regarding vaccine safety and efficacy along with availability reports.

Acknowledgements

This project was approved by the Institutional Review Board of the University of Pittsburgh. This publication/project was funded by an Association of Teachers of Preventive Medicine (ATPM)–Centers for Disease Control and Prevention (CDC) cooperative agreement (TS-0550-16/16). The contents are the responsibility of the authors and do not necessarily reflect the official views of the CDC or ATPM. We are grateful to Richard Bruehlman, MD, for assistance with data collection and project design.

This

References (24)

N.H. Fiebach et al.
Patient acceptance of influenza vaccination
Am J Med
(1991)
R. MacDonald et al.
Validation of self-report of influenza and pneumococcal vaccination status in elderly outpatients
Am J Prev Med
(1999)
K.L. Nichol et al.
Estimation of outpatient risk characteristics and influenza vaccination statusvalidation of a self-administered questionnaire
Am J Prev Med
(1991)
K. Fukuda et al.
How the delayed distribution of influenza vaccine created shortages in 2000 and 2001
Proc Annu Symp Comput Appl Med
(2002)
Centers for Disease Control and Prevention. Delayed supply of influenza vaccine and adjunct ACIP influenza vaccine...
R.K. Zimmerman et al.
A comprehensive investigation of barriers to adult immunizationa methods paper
J Fam Pract
(2001)
T.A. Santibanez et al.
Knowledge and beliefs about influenza, pneumococcal disease, and immunizations among the elderly
J Am Geriatr Soc
(2002)
Zimmerman RK, Santibanez TA, Janosky JE, et al. What affects influenza vaccination rates among older patients? An...
D.E. Montano
Predicting and understanding influenza vaccination behavior. Alternatives to the health belief model
Med Care
(1986)
A.R. Davidson et al.
Cross-cultural model testingtoward a solution of the etic-emic dilemma
Int J Psychol
(1976)

P. Valois et al.

A comparison of the Fishbein and Ajzen and the Triandis attitudinal models for the prediction of exercise intention and behavior

J Behav Med

(1988)

D. Landis et al.

Habit and behavioral intentions as predictors of social behavior

J Soc Psychol

(1978)

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Research articleShortage of influenza vaccine in 2000–2001: Did it change patient beliefs?☆

Abstract

Objectives

Methods

Results

Conclusions

Introduction

Section snippets

Subjects

Response rate

Demographics

Discussion

Conclusions

Acknowledgements

Am J Med

Am J Prev Med

Am J Prev Med

How the delayed distribution of influenza vaccine created shortages in 2000 and 2001

Proc Annu Symp Comput Appl Med

A comprehensive investigation of barriers to adult immunizationa methods paper

J Fam Pract

Knowledge and beliefs about influenza, pneumococcal disease, and immunizations among the elderly

J Am Geriatr Soc

Predicting and understanding influenza vaccination behavior. Alternatives to the health belief model

Med Care

Cross-cultural model testingtoward a solution of the etic-emic dilemma

Int J Psychol

A comparison of the Fishbein and Ajzen and the Triandis attitudinal models for the prediction of exercise intention and behavior

J Behav Med

Habit and behavioral intentions as predictors of social behavior

J Soc Psychol

Research article
Shortage of influenza vaccine in 2000–2001: Did it change patient beliefs?☆