Robert F. Kennedy, Jr., is called by his own family for his anti-vax conspiracy theories

While the United States has had its worst measles outbreak for years, partly because of unvaccinated people contracting the virus, its own family is denouncing its anti-vaccine stance.

On Wednesday, Kathleen Kennedy Townsend and Joseph P. Kennedy II (D-Mass.), A former congressman, as well as her niece Maeve Kennedy McKean, published an article in Politico magazine accusing her of "complicity" in a misinformation campaign.

"Robert F. Kennedy Jr. (…) is part of this campaign to attack institutions committed to reducing the tragedy of preventable infectious diseases," they wrote. "He has helped spread false dangerous information on social media and is complicit in sowing mistrust of the science behind vaccines."

"We love Bobby," they said, praising his record on the environment. "However, on vaccines, he is wrong."

Family members highlight the work done by other members of the Kennedy family, including President John F. Kennedy, in promoting public health. President Kennedy lobbied for the Americans to vaccinate their children and, in 1962, signed the Vaccination Assistance Act establishing the first national immunization programs.

[The truth about vaccines, autism and Robert F. Kennedy Jr.’s conspiracy theory]

But Robert F. Kennedy Jr. has taken a decidedly different path from his famous uncle. In 2005, he alleged in an article in Rolling Stone and Salon that an ingredient called thimerosal, contained in some vaccines, was dangerous and that the government was hiding its links with autism. It contained numerous factual errors, for which Rolling Stone had to publish several corrections. Salon eventually removed the story and removed it from its website.

He continued to write and make speeches on the widely refuted claims that vaccines are the cause of autism and runs a group called "Children's Health Defense", which disseminates misinformation about the risks posed by vaccines.

In 2000, measles was declared eliminated from the United States through vaccination practices in the country. According to the latest CDC figures, 764 cases of measles in 23 states have already been reported.

The latest US outbreaks are thought to have been caused by travelers bringing the virus from countries with a high measles outbreak. When unvaccinated people are exposed, they are likely to be infected with the highly contagious virus. The disease can spread quickly in communities where the number of people vaccinated is not enough to prevent an epidemic.

The anti-vaccine sentiment has taken root in several places in the United States, creating dangerous conditions for the spread of the virus. Some communities in Washington state have low vaccination rates because of parents' belief that vaccines could harm their children. The state legislature in Washington passed a bill that would make it more difficult for parents to prevent their children from escaping the measles, mumps and rubella vaccine. He is waiting for the signing of Governor Jay Inslee (D).

A misinformation campaign on vaccines targeting orthodox Jews in New York would have made the community vulnerable to the virus. According to the city's health department, 466 measles cases have been confirmed in the Brooklyn and Queens boroughs since September. Most cases involved the Jewish community.

Last week, Health and Social Services Secretary Alex Azar said epidemics posed an increasing risk to public health.

"We have come a long way in the fight against infectious diseases in America, but we risk going back and seeing our families, neighbors and communities unnecessarily suffering from preventable diseases," Azar said.

In April, the Food and Drug Administration issued a long and harsh statement by Peter Marks, director of the FDA's Center for Evaluation and Research on Biologics, urging Americans to vaccinate.

"We can not say enough," said Marks, "The overwhelming scientific evidence shows that vaccines are among the most effective and safest interventions to prevent disease and protect public health."

Lena Sun contributed to this report.

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