The U.S. is experiencing its largest measles outbreak in a quarter-century with no end in sight and its epicenter is in New York’s Hasidic Jewish communities, where anti-vaccination misinformation is posing a problem for health officials trying to end the outbreak.

"The biggest challenge we face right now is misinformation and myths about the vaccine. It's important that parents realize that the vaccine is safe and effective," Dr. Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, told Fox News.

Anti-vaccination propaganda targeted specifically to parents has popped out throughout Hasidic communities in Williamsburg, Brooklyn and in Rockland County, N.Y. and it appears to have convinced some mothers that the vaccines are more dangerous than the disease. The vast majority of the 704 confirmed measles cases in 22 states are located in these communities, according to the Centers for Disease Control's (CDC) latest data, released Monday. Of those cases, 432 are in Brooklyn.

An anti-vaccination organization known as PEACH has published a 40-page booklet, filled with misinformation and discredited science about why it says vaccines are unsafe. Among the many discredited claims are that vaccines cause autism and are made of aborted fetuses.

The booklet quotes well-known rabbis who say it’s all right to keep children and unvaccinated and to send them to school. It even compares the U.S. government to the Nazis.

"The Nazis argued that their experiments were for 'the greater good of society,'" the booklet reads. "Our right to refuse medical treatment is denied in the name of public health (precisely the logic used by the Nazis)."

Other so-called "anti-vaxxers" have posted flyers with the image of a vaccine needle attached to a handgun imploring, "Vaccines are dangerous!"

Health officials in Rockland County, N.Y. told Fox News the misinformation has convinced enough mothers in the Hasidic community there to spark the longest ongoing measles outbreak since the disease was eradicated in the U.S. in 2000. As of Monday, there are 202 confirmed measles cases in the enclave about 45 minutes north of New York City.

"It's very frustrating because it’s misinformation. It's misguiding people in the community and the concern with this group is that they are affecting a population where a lot of what is decided by moms, is by word of mouth," said Rockland County Health Commissioner Dr. Patricia Ruppert.

An Orthodox Jewish Vaccination Task Force, made up of more than a dozen Jewish medical professionals, has published their own pamphlet called PIE to debunk all the false claims made by PEACH. Blima Marcus, the head of the task force, says other mothers in the Hasidic communities are more influential than rabbis.

"They don't turn to rabbis for daily decisions like preventive care," Marcus said. "They [anti-vaxxers] are using all of the emotional fear factors. There is nothing more fearful to a woman than that you're going to injure your child."

The anti-vaxxers even make robocalls to homes and have given out a hotline number for people to join in live teleconferences where misinformation is spread, and vaccination facts are stymied.

"When I have been on the call just to listen, I have heard those who have spoken with scientific information and the importance of vaccination and they have been dismissed very quickly from the call many times," Dr. Ruppert said.

To combat the anti-vaccination messaging, the New York City Department of Health has made 30,000 robocalls in English and in Yiddish. They have also published posters and handouts in both languages informing the community about the benefits of vaccinations. The city has also issued a rare mandatory vaccination order for all adults and children in the affected zip-codes in Williamsburg. In Rockland County, emergency orders have been issued that keep all of those with the measles or those who have been exposed to the measles from going out in public.

The orders have encouraged more than 40,000 MMR vaccinations since the outbreaks began in October. In Rockland County, officials say there are still likely a couple of thousand children who are still not vaccinated and a mandatory vaccination order would be the likely next step if the outbreak continues.

Schools in both New York communities have been ordered to exclude unvaccinated children from attending. The NYC Department of Health has shut down seven schools for failing to comply with the city, five of which had been reopened as of Monday.

The outbreaks in New York began when unvaccinated travelers, primarily children, traveled to Israel and became infected in October. The CDC says the combination of imported measles from Israel, Ukraine and the Philippines and a higher than average non-vaccination rate in the Hasidic communities has fueled the Measles outbreak.

In all, the number of Measles cases worldwide is up 300 percent because of the increased growth of under-vaccinated communities. The CDC says some 75 percent of measles cases over the last five years have emerged in insular communities like the Amish or Hasidic Jews. These communities are tighter knit, have more children, and are susceptible to misinformation.

The CDC expects the outbreak to continue and the number of cases to go up, but in the meantime, some Orthodox leaders are concerned that the growing attention may fuel anti-Semitic sentiments.

"The fact of the matter is there are anti-vaxxers in every community in every way of life," said Yossi Gestetner, spokesman for the Orthodox Jewish Public Affairs Council. "I am very concerned about the potential of profiling and anti-Semitic incidents."

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Rabbis reiterate that the Jewish religion does not prohibit vaccinations. Still, thousands of people are said to have religious exemptions for vaccines in New York.

On Monday, Rockland County officials rallied at the state capitol in Albany in support of a state Senate bill that would ban religious exemptions to vaccinations.

“A mixture of complacency, misinformation, skepticism about immunizations and a lack of access to these shots has led to inadequate vaccination rates globally,” Rockland County Executive Ed Day said. “As a state and a nation, we need to address this now."