Background: Pneumococcal disease is a major cause of morbidity and dea
th, especially among elders and other people at high risk. In spite of
long-standing national recommendations for its use, pneumococcal vacc
ine is underused, with 70% or more of targeted persons as yet unimmuni
zed. Concern about side effects is a barrier to successful vaccine del
ivery. Methods: Persons attending a walk-in pneumococcal vaccination c
linic were surveyed by use of structured telephone interviews. They we
re asked about health characteristics and local and systemic symptoms
experienced during the week after their vaccination (postvaccination p
eriod). These responses were compared with the symptoms they reported
for the 7 days immediately preceding their interview (the comparison p
eriod). Results: A total of 1006 persons were interviewed a mean of 65
.4 days after their vaccination. They had an average age of 69.9 years
, and approximately 95% were in a high-risk group targeted for pneumoc
occal vaccination. For all systemic symptoms including fever rash, mya
lgias, fatigue, malaise, and headache, subjects reported similar or lo
wer rates during the postvaccination week than during the comparison w
eek. Local reactions occurred in 28.2% of subjects. These local sympto
ms were mild to moderate for more than 90% of subjects and rarely resu
lted in the need to decrease the use of their arm. Conclusion: Pneumoc
occal vaccination was not associated with an increase in systemic symp
toms but was associated with mild to moderate local symptoms in about
one fourth of vaccine recipients. These findings should help health ca
re providers and their patients address an important barrier to pneumo
coccal immunization.