About 1 in every 8 children in the United States is at risk of contracting measles due to gaps in vaccinations, according to new research released today.

Nationwide, that means nearly 9 million children are at risk of one of the most contagious diseases, which at one point had been officially eradicated in this country.

Measles Risk

Nearly 1 in 4 children aged 3 or younger are at risk. Of those children, 2 million are less than a year old.

“They can’t be vaccinated. They’re too young,” said lead study author Robert Bednarczyk, Ph.D., assistant professor in the Hubert Department of Global Health, Rollins School of Public Health at Emory University in Atlanta.

In addition, nearly 5 percent of 17-year-olds in the United States have not had even one measles-mumps-rubella (MMR) vaccination.

The findings are being reported at an annual conference this week of the Infectious Diseases Society of America.

Overall, Bednarczyk doesn’t find these new figures alarming, but he isn’t comforted by them either.

“We are at a decent point, but we could do better,” he said.

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Crucial Gaps in Herd Immunity

Measles was considered eradicated from the United States 15 years ago, but that doesn’t mean it doesn’t exist here.

As of September 18 of this year, 189 people in 24 states and the District of Columbia reported cases of measles, according to the U.S. Centers for Disease Control and Prevention (CDC).

The majority of those cases stemmed from an outbreak occurring at two Disney theme parks in southern California. That was the same strain responsible for a large measles outbreak in the Philippines in 2014.

While the majority of people who have been infected with measles in recent years were unvaccinated, “herd immunity” is important in preventing outbreaks from getting worse.

The U.S. population needs about a 94 percent vaccination rate to protect those who cannot be vaccinated and are at the highest risk of adverse effects of a measles infection. Those effects include pneumonia, encephalitis, hospitalization, and sometimes death.

The new research shows the United States teetering between 92 and 94 percent coverage.

Researchers estimate that if current vaccination levels drop by 2 percent, 14 percent of children — 1 in 7 — would be vulnerable to measles.

“Our buffer zone isn’t very high,” Bednarczyk said.

Those at higher risk and who aren’t healthy enough to be vaccinated include children under 12 months old and people with compromised immune systems, such as those undergoing cancer treatments.

“The concerns are for the ones who can’t be vaccinated,” Bednarczyk said.

According to the CDC, those healthy enough to receive their first dose of the MMR vaccine should receive it between the ages of 12 and 15 months. The second dose should come between the ages of 4 and 6 years.

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Scientists Reiterate That Vaccines Are Safe

Besides age and medical reasons, researchers say children are susceptible to a measles infection if their parents opt out for personal or religious reasons, their vaccination schedule is delayed, or they have not received the second dose of the vaccine.

While many preventable diseases like measles and whooping cough are seeing resurgences because of fears of vaccine safety, Bednarczyk and the scientific community agree that vaccines are safe and effective at preventing major outbreaks.

Since most of these outbreaks occur in clusters of unvaccinated people and aren’t regularly found in the general population, Bednarczyk says it’s an out of sight, out of mind mentality.

“We do live in a time where we don’t see these diseases,” he said. “We’ve done a good enough job to get them out of sight.”

The CDC has published numerous studies showing no link between vaccines and autism, a claim based on discredited science but held as dogma in certain circles.

Even a study commissioned by the anti-vaccine group SafeMinds, which still claims that immunizations cause autism, showed no connection. The study, published in the Proceedings of the National Academy of Science, tested vaccines on infant monkeys. At the end of the study, none of the animals showed any neurological or behavioral changes as are seen in autism.

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