"In America they tried to do this and the courts stopped them so it can be complicated, but really it's people's responsibility as a parent to do the right thing - the right thing for their own children as well as, of course, the right of the community that everybody lives in".
This year's record-setting outbreak threatens that achievement.
According to the CDC, a disease is eliminated from a geographic region when no more endemic cases of the disease occur within that region.
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Those over 50 are considered immune as the disease was widespread in childhood, according to the ARPHS.
Essentially everyone got it. "Others may face serious complications".
"People had experienced the harm measles could do and so were receptive to the vaccine when it came out", says Najera.
The department has Measles, Mumps and Rubella (MMR) vaccine for children and adults. Two doses of MMR vaccine are about 97% effective at preventing measles. Orders for some people to avoid public places in Rockland County, New York. During this time, states began adopting laws requiring proof of immunization to enroll in public schools.
"It can help, but it can't hurt", Giorgio said. "The only way to protect against measles is to get vaccinated".
In Dudley, it was 1,127 children who had not received their first MMR vaccination by the age of five, and a further 1,613 failed to have the second injection.
Currently, the Centers for Disease Control and Prevention (CDC) recommends that children get two doses of the measles, mumps and rubella (MMR) vaccine, unless they have specific allergies or prohibitive medical conditions. Before the measles vaccination program started in 1963, an estimated 3 to 4 million people got measles each year in the United States.
The pages of the Chatham Monitor from the 1800s show many references to measles, both in its coverage of families who reported cases and in the many elixirs and tonics advertised to treat the disease.
Although a lack of vaccination threatens herd immunity, that's not the only threat. According to public health officials, most of the people suffering from measles were unvaccinated.
Kevin Sumner, the president of the Middle Brook Regional Health Commission in New Jersey, told Fox Business that the U.S.is in the 70 percent range.
As measles spreads fast, diagnosis becomes more essential.
It's one thing to isolate someone with measles or to quarantine someone who has been exposed, he said. "We want them fully protected", Dr. Wexler says. "If these numbers continue to climb and new cases pop up that aren't associated with foreign travel, we're there". The current outbreaks are believed to trace back to visits to Israel and Ukraine.
The virus has been found in 22 states while more than 66 people have been hospitalised across the US. "This year, we're celebrating 25 years of national infant immunization week". The cause? Vaccine refusals. This could still be prevented if vaccination rates in these communities go up. "These are completely preventable outbreaks". And some local communities have even lower rates. At what point does this warrant more action from the federal government? Vaccine costs will be billed to insurance. "But we're not there yet".
MARTIN: Their vaccination level, yeah.
"We know vaccines are safe because they're among some of the most studied medical products we have".
An earlier version of this story misspelled Thomas C. Peebles' last name as Pebbles.