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President-elect Donald Trump has asked vaccine skeptic Robert F. Kennedy, Jr. to chair a commission looking into the safety of vaccines, Kennedy said Tuesday, stunning doctors and puzzling experts everywhere.
Kennedy’s views on vaccines have been widely discredited, and the publications Salon and Rolling Stone have retracted and taken down stories that Kennedy, who has no medical background, wrote about vaccines.
"President-elect Trump has some doubts about the current vaccine policies and he has questions about it," Kennedy told reporters Tuesday.
It’s a here-we-go-again moment for vaccine experts and pediatricians, who are exasperated with having to explain to people over and over again that the issue of vaccine safety is settled.
Decades of study have shown no link at all between vaccines and autism.
Related: 7 Vaccine Myths Debunked
The Centers for Disease Control and Prevention, the Institute of Medicine (now the National Academy of Medicine) and various independent groups have debunked, often multiple times, every assertion made in the past 20 years by a small but highly vocal group of vaccine critics.
"It's been answered again and again and again," says Dr. Paul Offit, a pediatrician at Children's Hospital of Philadelphia who has written broadly on the vaccine doubters.
Vaccines are among the safest medical interventions known, the World Health Organization says.
“Vaccines are safe. Vaccines are effective. Vaccines save lives,” the American Academy of Pediatrics said in a statement rushed out after Kennedy’s statements.
“Claims that vaccines are linked to autism, or are unsafe when administered according to the recommended schedule, have been disproven by a robust body of medical literature,” the Academy added.
“Delaying vaccines only leaves a child at risk of disease. Vaccines keep communities healthy, and protect some of the most vulnerable in our society, including the elderly, and children who are too young to be vaccinated or have compromised immune systems.”
While no drug or treatment is 100 percent safe, they say vaccines are far, far safer than the diseases they prevent.
“Immunization averts an estimated 2 to 3 million deaths every year from diphtheria, tetanus, pertussis (whooping cough), and measles,” the World Health Organization says.
In contrast, just 57 claims of deaths due to measles vaccines have been filed through the U.S. Vaccine Injury Compensation Program, a no-fault system set up to compensate people injured by vaccines. The program doesn't say how many of those claims were actually allowed.
A special federal court, the U.S. Court of Federal Claims, ruled against three families in 2009 who claimed vaccines caused their children's autism, saying they had been "misled by physicians who are guilty … of gross medical misjudgment."
"There is not a year that goes by at Children's Hospital of Philadelphia where we do not see a child die from a vaccine preventable disease, typically influenza," Offit said. "Less commonly it's pneumococcal, occasionally it's pertussis or whooping cough."
The Institute of Medicine looked at the question so many times that it issued a final report in 2001 saying these studies were using money that could be better spent elsewhere to find the causes of autism.
Yet when activists kept up their clamor, the independent organization released another report in 2005 saying there really, really is no link between vaccines and autism.
It did say doctors and public health experts were doing a poor job of explaining this to people.
Related: Don't Call Vaccine Doubters Dumb
Studies have especially focused on a mercury-based preservative called thimerosal, which keeps dangerous bacteria and fungi from growing in vials of vaccines.
Researchers have been unable to find evidence thimerosal in vaccines can damage human brains – it’s in a form the body processes quickly -- but drugmakers took it out of all childhood vaccines anyway years ago because of the fears.
And vaccine makers have changed vaccine formulations over the years to mollify other worries. The whooping cough vaccine was reformulated in the 1990s because of side effects that included pain and swelling from the shot and fever. But there's some evidence the newer vaccines doesn't protect as well and that recent outbreaks of whooping cough may be the result of reformulating the vaccines.
Another question is whether some kids are super-sensitive to vaccines.
Dr. Anjali Jain of The Lewin Group, a health consulting group in Falls Church, Virginia, compared kids who hadn't been vaccinated because of a family history of autism to kids who had gotten their shots.
They found the risk of autism was less than one percent in vaccinated kids, whether they had an older sibling with autism or not.
Other researchers have answered questions about whether kids get too many vaccines at once— they don't.
Lawmakers have begun cracking down on parents who want to choose, saying these choices endanger not only the children not being vaccinated properly, but others in the community.
Research into the effects of Zika virus infection is clearly showing that particular virus can get into a developing baby's brain and damage it.
Just this weekend, the director of the Cleveland Clinic’s Wellness Institute caused a furor with a blog post questioning not exactly the safety of vaccines, but raising questions about some of the preservatives used in them.
The Cleveland Clinic responded quickly by saying it fully supports vaccines. Vaccine experts note there are also no medical questions about vaccine ingredients.
Related: Doctors Say Get your Kids Vaccinated
Another common myth: that the very existence of the federal Vaccine Injury Compensation Program proves vaccines are harmful.
But former California Rep. Henry Waxman, who helped write the legislation that led to the program's 1986 launch, has said it was set up because vaccine makers were dropping out of the business because of fear of pricey lawsuits, and public health officials feared the U.S. would suffer a shortage of vaccines.
It is a no-fault system. If people could prove they suffered an injury that has been known to be caused by vaccine, they could be compensated without having to prove the vaccine caused the problem.
It's paid for by a tax on vaccines.