It periodically saturates the media, so no doubt most parents have heard the rumor: vaccines may cause autism.

This is not the first time vaccines have been implicated as a cause of unfortunate health phenomena in childhood, says Mills-Peninsula pediatrician James Ferrara, M.D.

“There was another widely circulated – and false – myth years ago that the Diphtheria, Tetanus, Pertussis (DTP) vaccination was linked to crib death, also known as Sudden Infant Death Syndrome,” he said.

“Despite all evidence to the contrary, it was difficult to convince some parents. Once we determined the relationship between sleep position and crib death incidence, a lot of the fear was relieved.”

With pervasive misinformation and the accompanying fear, it can be hard to know what to believe.

“Parents have their children’s safety at heart,” the doctor says. “Nonetheless it’s our responsibility to weigh all evidence and give the best advice we can – to vaccinate according to guidelines.”

Still some parents decide to omit some or all vaccines.

Not vaccinating puts a child at risk of unprotected exposure to certain bacteria and viruses.

“The individual risk is small, but if thousands don’t vaccinate, the risk that one child will get a disease increases significantly,” Dr. Ferrara says.

A highly vaccinated population helps shield infants too young for vaccines.

“Since infants cannot be vaccinated for certain diseases for the first two months of life, and others until they are over one year, they are vulnerable during that time,” he says. “But if the overall population is highly vaccinated, that risk is minimized. Therefore vaccinating is a public health
issue, not just an individual issue.”

Here are some popular myths about childhood vaccinations and the facts every parent should know.

Myth: Vaccines cause autism
“The preponderance of scientific evidence disproves a connection between vaccinations and autism,” Dr. Ferrara says.

One cause of the myth’s endurance has to do with timing, he says.

“Most autistic spectrum disorders first manifest during the child’s second year when they start to show developmental regression,” he says. Because these events come on the heels of a number of vaccinations, the coincidence can be mistaken for cause and effect.

“There is significant research ongoing that will hopefully shed light on the true causes of autism. Until we have a better understanding of these issues, it will be difficult to dispel the belief that vaccines are the cause.”

Myth: Now that major diseases are eradicated, we no longer need to vaccinate
The bacteria and viruses that cause some fearsome illnesses – whooping cough, meningitis, epiglottitis, diphtheria, tetanus, etc. – are still around, but the diseases they cause are uncommon only because vaccine
rates are high, Dr. Ferrara said.

“The risk of a U.S. born child getting exposed to polio is minimal. But it does exist in certain areas of the world where the population hasn’t been vaccinated,” he said. “Until it is eradicated worldwide, we won’t take the chance of discontinuing the vaccine.”

In areas where vaccination rates drop for any reason, the disease rate increases.

“We saw that with pertussis when people weren’t getting vaccinated because of crib death fears,” he said.

Myth: My baby could get the disease from the vaccine
This fear primarily derives from the oral polio vaccine, which was once made with live weakened virus and carried a small risk of developing the disease.

Most vaccines today are inactivated, with a few exceptions including measles, mumps, rubella (MMR) and chicken pox. Children with normal immune systems are not at risk for contracting the disease from the vaccine. Highly immune compromised people, such as those on chemotherapy, typically will not receive attenuated, or live, vaccines,
the doctor said.

Myth: Giving multiple vaccines at the same time will harm my child
There is no increased risk to a child’s health in giving multiple vaccines at the same time, Dr. Ferrara says.

“What we ask of the immune system as a result of vaccines – even several vaccines at the same time – is incrementally small compared to what the immune system does on a daily basis in protecting us from infection from normal bacteria. The immune system is very capable of multitasking.”

For a complete list of Mills-Peninsula pediatricians, visit www.mills-peninsula.org/healthpoint.