A letter to the Editor claiming autism can be caused by the vaccines given to young children has been called "hysterical" and "irresponsible" by members of Bermuda's medical profession.

"The evidence linking the MMR (mumps/measles/rubella) vaccine to autism has been utterly disproven," said paediatrician Dr. Peter Perinchief.

And the Centers for Disease Control (CDC) in the US said on their website: "The weight of currently available scientific evidence does not support the hypothesis that vaccines cause autism.

"We recognise there is considerable public interest in this issue, and therefore support additional research regarding this hypothesis."

The letter to the Editor which ran recently in The Royal Gazette discusses the "highly probably link between immunisations and autism".

"This link has been made in particular between mercury and autism," the author wrote. "Up until about three years ago, and thus from the early 1990s until about 1999, almost all childhood vaccinations contained thimerosal, a form of mercury.

"Personally I feel that our children are guinea pigs as we won't know for several years what the combined effect of these vaccinations will be ... In many cases of autistic children, these children are perfectly normal until they have received this shot! And yet many deny the connection. I feel with all of my heart for the Crow family and others dealing with autistic children."

However the letter drew a response both from the medical profession as well as the family the author named in the letter.

"As the parents of three autistic children we have more motivation than most to discover the cause of this condition," wrote Michael and Tricia Crow in a response to The Royal Gazette.

"The scientific evidence is very clear: Numerous studies have been done using data from millions upon millions of children, and every one of these studies has failed to demonstrate any evidence of a link between autism and childhood vaccinations."

"It is the consensus of the world medical body that we are not going to stop giving MMRs," said Dr. Perinchief.

Agreeing that concerns about thimerosal were valid and saying thimerosal had been removed from use in vaccinations, Dr. Perinchief added however: "If we stopped giving MMRs the effects would be horrendous.

"One in 1,000 kids would wind up with adverse neurological problems, one in 10,000 would die ... Everyone's forgotten what these diseases are like.

"(Vaccinations) are for the greater good. It's understood there will be problems but they are one of the spin-offs you have to accept for the greater good ... It's a tiny percent that have problems. To stop would be madness."

And the Crow family agreed with him.

"Childhood vaccines are a vital element of general efforts to prevent disease," they wrote.

"This is a difficult discussion, as it requires us to trust our medical advisers and act in the interest of society as a whole. Thus, many parents who become alarmed at stories of a link between vaccinations and autism think they are being responsible parents by refusing vaccinations ... They are not.

"The child most at risk is the six-month old baby next door who is too young to be vaccinated and who is most likely to die from a general outbreak of measles.

"We have more reason than anyone to find a cause, and someone to blame, for our children's condition. Vaccines are not the answer. We strongly encourage everyone to make sure their children get vaccinated."