Poliovirus vaccine contaminated with live simian virus 40 (SV40), a macaque polyomavirus
that is tumorigenic in rodents, was used extensively in the United States between
1955 and 1963. Simian virus 40 DNA has recently been detected in several rare human
tumors, including ependymomas, osteosarcomas, and mesotheliomas.
To determine the risk of ependymoma, osteosarcoma, and mesothelioma among Americans
who as children received SV40-contaminated poliovirus vaccine.
Retrospective cohort study using data from the Surveillance, Epidemiology, and End
Results program (1973-1993) and the Connecticut Tumor Registry (1950-1969), as well
as national mortality statistics (1947-1973).
United States.
Birth cohorts that were likely to have received SV40-contaminated poliovirus vaccine
as infants, born 1956 through 1962 (60 811730 person-years of observation); as children,
born 1947 through 1952 (46430953 person-years); or that were unexposed, born 1964
through 1969 (44959979 person-years).
Relative risk (RR) of each cancer among exposed compared with unexposed birth cohorts.
Age-specific cancer rates were generally low and were not significantly elevated in
birth cohorts exposed to SV40-contaminated vaccine. Specifically, compared with the
unexposed, the relative risk of ependymoma was not increased in the cohorts exposed
as infants (RR, 1.06; 95% confidence interval [CI], 0.69-1.63), or as children (RR,
0.98; 95% CI, 0.57-1.69) nor did the exposed have an increased risk of all brain cancers.
Osteosarcoma incidence also showed no relation to exposure as infants (RR, 0.87; 95%
CI, 0.71-1.06) or children (RR, 0.85; 95% CI, 0.59-1.22). Last, mesotheliomas were
not significantly associated with exposure, although the cohorts studied have not
yet reached the age at which these tumors tend to occur.
After more than 30 years of follow-up, exposure to SV40-contaminated poliovirus vaccine
was not associated with significantly increased rates of ependymomas and other brain
cancers, osteosarcomas, or mesotheliomas in the United States.