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Vaccine Safety
Survey Results: State Vaccine Safety Activities
States Report on Responding to Inquiries About Vaccine Safety

Since 1999, the National Immunization Program (NIP) has included questions on its annual survey of state immunization program managers regarding the amount of time their programs spend responding to vaccine safety inquiries and the specific questions they most frequently receive. The most recent survey was sent to states in December of 2001 and the data was collected by NIP in March 2002. The program manager is responsible for completing the survey, but may receive assistance from coordinators who may be more familiar with the information relevant to certain sections of the survey.


Survey Data
State immunization program managers were asked to report the types and percentages of vaccine safety related public inquiries they responded to in the past year. The proportion of participants who reported that the focus of more than 15% of their public inquiries were related to vaccine safety issues increased from 23% in 1999 to 35% in 2001. Forty-five percent of respondents in 2001 reported that the number of vaccine safety questions they received from parents/general public increased in the past year; 69% of respondents in 1999 and 70% of respondents in 2000 reported increases. Thirty-seven percent of respondents in 2001 said that the number of questions they received from health care professionals increased in the past year; 62% of respondents in 1999 and 61% of respondents in 2000 reported increases.

Table 1: State program managers reported increases in vaccine safety issues in 1999, 2000 and 2001

% of state program managers who reported an INCREASE in the… 1999 2000 2001
amount of time spent on vaccine safety issues NA 70% 43%
number of parent and general public questions about vaccine safety 69% 70% 45%
number of provider questions about vaccine safety 62% 61% 37%
number of persons claiming religious or philosophical exemptions to immunization 18% 31% 34%
Percentage of grantees who reported that parental concerns about vaccines have affected overall immunization rates 23% 16% 33%

In 2001, program managers reported that during the previous year the questions they most frequently received about vaccines involved vaccine administration, schedules, and storage1 (69%), vaccine exemptions (53%), additives in vaccines (24%), contraindications to vaccination (20%), known side effects (18%), individual antigen versus combination vaccines (18%), and the effect of multiple vaccines on the immune system (14%). These percentages are similar to those from the 1999 and 2000 surveys with the exception that in 2000 the second most frequently received question concerned the effect of multiple vaccines on the immune system. Thirty-three percent of 2001 respondents indicated that the effect of multiple vaccines was the most difficult issue to address, followed by questions regarding vaccine additives (18%), administration, scheduling and storage (18%), exemptions (12%), unproven side effects (12%), and contraindications (7%). By comparison, in 2000 'unproven side effects' was indicated by 63% of respondents as the most difficult issue to address (the effect of multiple vaccines was reported as the third most difficult issue).

Table 2: Types of vaccine safety questions that were the most difficult to address during 2000 and 2001 (1999 data not available)

  2000 2001
Additives in vaccines 15% 18%
Contraindications to vaccines 2% 7%
Effect of multiple vaccines on the immune system 10% 33%
Unproven side effects 63% 12%
Vaccine exemptions 4% 12%
Vaccine administration, schedules and storage 2% 18%

No program manager reported a decrease in religious or philosophical exemptions in 2001, and 34% of respondents reported an increase; results from the previous two years were similar. Finally, a higher percentage of respondents in 2001 (33%) than in 1999 (23%) or 2000 (16%) reported that parental concerns about vaccines and vaccine safety affected overall immunization rates for their state.


Clearly, the art of addressing vaccine safety concerns through effective risk communication has emerged as, and continues to be, an increasingly important skill for managers of mature immunization programs. Visit the NIP website
for information that may assist immunization programs in addressing some of the difficult vaccine safety issues such as vaccine ingredients, the effect of multiple vaccines on the immune system, and vaccine administration, schedules and storage.

1 The category 'administration, schedules and storage' included vaccine shortages and delays; these issues were not a separate option.

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This page last modified on August 15, 2002


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