It is not only the CDC but many non-government scientific and medical bodies that state that there is no link between vaccines and autism, including the American Medical Association, the American Academy of Pediatrics, US National Academy of Sciences and probably your pediatrician ("Vaccines and autism," May 3). The 1998 scientific paper claiming a link between vaccines and autism has since been found to be fraudulent and the author banned from practicing medicine in the UK. As a precaution, mercury has been removed from children's vaccines since 2001, yet the incidence of autism continues to increase.

Yes, anecdotally, some children seem to have a temporal association between their vaccination and any number of adverse events. But there is a big difference between association and causation. Millions have been vaccinated without any problems at all. While any medical intervention carries some risk, the risk of vaccination pales in comparison to the risk of not vaccinating. It wasn't long ago that many thousands of children suffered serious illness, permanent disability and even death by diseases such as smallpox, polio and others that are now prevented by vaccines.

Greg Livermore