It was in 1960 that an NIH scientist named Bernice Eddy discovered that rhesus monkey kidney cells used to make the Salk polio vaccine and experimental oral polio vaccines could cause cancer when injected into lab animals. Later that year the cancer-causing virus in the rhesus monkey kidney cells was identified as SV40 or simian virus 40, the 40th monkey virus to be discovered.
Sadly, the American people were not told the truth about this in 1960. The SV40 contaminated stocks of Salk polio vaccine were never withdrawn from the market but continued to be given to American children until early 1963 with full knowledge of federal health agencies. Between 1955 and early 1963, nearly 100 million American children had been given polio vaccine contaminated with the monkey virus, SV40.
… Today, there are scientists associated with the US government who continue to deny that SV40 causes human cancer or that SV40 associated cancers have had any effect on cancer rates since the early 1960’s. However, highly credentialed non-government scientists in multiple labs around the world continue to identify SV40 in human brain and lung cancers of children and adults and are finding that SV40 is also associated with bone cancers and Non-Hodgkin’s Lymphomas. The majority of these independent scientists have concluded that, yes, SV40 does cause human cancers.
— Barbara Loe Fisher, co-founder and president of the National Vaccine Information Center (NVIC)
Fisher BL. The SV40 Virus: Has Tainted Polio Vaccine Caused An Increase in Cancer? NVIC.org.