evidence: Do Vaccines or Thimerosal Cause Autism? No. Many studies have found no link between vaccines and autism. And a 2004 report from the Institute of Medicine (IOM) found that thimerosal (an organic mercury compound used as a preservative in vaccines since the 1930s) does not cause autism. Recent studies have not shown any cognitive and behavioral problems in babies who have gotten thimerosal-containing vaccines. And now, vaccines for infants and young children contain no or very little thimerosal. [...] There are concerns, many of which circulate on the Internet, linking some vaccines to multiple sclerosis, sudden infant death syndrome (SIDS), and other problems. To date, studies have not shown any connection between vaccines and these conditions. SIDS cases have actually dropped by more than 50% in recent years, while the number of vaccines given yearly continues to rise.