LOS ANGELES (CBSLA.com/AP) — A measles outbreak centered in California has sparked a national debate over parents who choose not to vaccinate their children.

The outbreak, which has sickened over 100 people, has focused attention on so-called “anti-vaxxers”, those who opt out their kids from vaccination due to religious or philosophical reasons, or controversial fears that vaccines can lead to autism and developmental disorders.

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KNX 1070’s Pete Demetriou reports a California Department of Public Health official wants to reassure parents the measles, mumps, and rubella (MMR) vaccine is safe.

Dr. Kathleen Harriman, Chief of the state Department of Public Health’s Vaccine Preventable Disease section, said while there are always pockets of people who are susceptible to measles, the existence of non-inoculated groups could raise the risk of making the disease even more widespread.

“This happened in France in 2011 when we had thousands of cases and it really was due to immunization rates getting too low to really control measles,” said Harriman.

Only children who have a medical contraindication to vaccines – such as an allergic reaction or severe immunodeficiency – should avoid being vaccinated for measles, according to Harriman.

“Certainly, there can be reactions to any vaccine, and that’s always been the case and always will be the case,” she said.

But a growing number of doctors and other medical experts such as as Santa Monica-based pediatrician Dr. Jay Gordon thinks the value of vaccines has been overstated.

Gordon, who says the majority of his patients are not vaccinated for measles, mumps or rubella, told CBS News he believes the current outbreak is being overhyped.

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“This is definitely being over promoted as a large and dangerous outbreak,” said Dr. Gordon. “Right now we don’t have that many cases of measles, and we should speak a little more quietly, we’re actually panicking people.”

Gordon added the last reported fatal case of measles in the United States was over a decade, a fact he says proves the “complication rate is very low in healthy children.”

Top public health officials, meanwhile, appeared Tuesday on Capitol Hill to update lawmakers on the measles outbreak that began at Disneyland in December.

Four different experts, including Dr. Anthony Fauci of the National Institutes of Health, testified at a House hearing and strongly endorsed the idea of mandatory measles vaccinations – an idea supported by a growing number of Democrats in Washington.

But those same experts were also under fire amid questions about why this year’s flu vaccine offered very little protection against the winter menace.

When lawmakers asked why the Centers for Disease Control and Prevention didn’t act months ago when concerns first arose to create a better-matched vaccine, CDC immunization chief Dr. Anne Schuchat says it wasn’t possible to change course.

While CDC first noticed a slight change in that strain last March, by the time the shift had become common in September, it was too late, the Associated Press reported.

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