“We love Bobby. He is one of the great champions of the environment. . . . We stand behind him in his ongoing fight to protect our environment,’’ the Kennedy relatives wrote in their joint op-ed. “However, on vaccines he is wrong.”

In an op-ed posted to the Politico website , former Massachusetts congressman Joseph P. Kennedy II, Kathleen Kennedy Townsend, and Townsend’s oldest daughter, Maeve Kennedy McKean, who runs Georgetown University’s Global Health Initiative, express love for their relative — but sharp disagreement on the value of vaccines.

In a rare public dispute, two of Robert F. Kennedy Jr.’s siblings and a niece are challenging his antivaccine stance in the wake of a measles outbreak they say is claiming more than 110,000 lives worldwide each year.


The anti-vaxxer movement, the op-ed said, is fueled by “internet doomsayers,” whose opposition to the use of vaccines are playing a negative role in the current outbreak in the United States linked to unvaccinated people, many of whom are children.

“Robert F. Kennedy Jr . . . has helped to spread dangerous misinformation over social media and is complicit in sowing distrust of the science behind vaccines,’’ the op-ed said. “His and others’ work against vaccines is having heartbreaking consequences.”

Robert F. Kennedy Jr., Joseph P. Kennedy II, and Kathleen Kennedy Townsend are all the children of Senator Robert F. Kennedy, who was assassinated in 1968 during a presidential run.

In the United States, 22 states are now reporting outbreaks of measles, and more than 700 cases have been reported so far this year, making 2019 likely to be the year with the highest number of measles cases in this country in decades, the op-ed said.

It’s a medical problem that can be solved through the use of vaccines, something the op-ed said that members of the Kennedy political clan advocated for while in positions of power in Washington.


In 1961, President John F. Kennedy publicly endorsed the use of the Salk vaccine for polio for some 80 million Americans, 5 million of whom were children. He also created the Agency for International Development, which has since supported vaccine programs in developing countries.

A year later, the president wrote to Congress asking for money for a national vaccination program. “There is no longer any reason why American children should suffer from polio, diphtheria, whooping cough, or tetanus . . . I am asking the American people to join in a nationwide vaccination program to stamp out these four diseases,’’ he wrote.

And US Senator Edward M. Kennedy, during his decades in the Senate, was a relentless supporter of legislative efforts to assure the widespread use of vaccines, while Robert F. Kennedy, appointed by his brother as US attorney general, pushed for “community empowerment models” that included public health improvements, the op-ed said.

“We are proud of the history of our family as advocates of public health and promoters of immunization campaigns to bring life-saving vaccines to the poorest and most remote corners of America and the world, where children are the least likely to receive their full course of vaccinations,’’ the op-ed said. “On this issue, Bobby is an outlier.”

The pro-vaccine Kennedys said parents are right to carefully consider vaccination for their children, but said the overwhelming medical evidence from decades of use shows vaccines are effective and safe, aside from some mild side effects.


“Those who delay or refuse vaccinations, or encourage others to do so, put themselves and others, especially children, at risk,” the op-ed said. “Everyone must communicate the benefits and safety of vaccines, and advocate for the respect and confidence of the institutions which make them possible. To do otherwise risks even further erosion of one of public health’s greatest achievements.”

John R. Ellement can be reached at ellement@globe.com. Follow him on Twitter @JREbosglobe.