Opinion: On childhood vaccines, candidates must separate  facts from alternative facts

In a video posted on Twitter in July, former President Donald Trump and Robert F. Kennedy Jr. exchanged conspiracy theories about the toxicity of childhood vaccines. This widely viewed conversation adds fuel to an alternative reality spread by the anti-vaccination movement.

In the video, Trump talked about “A vaccination that is like 38 different vaccines and it looks like it’s meant for a horse, not a, you know, 10-pound or 20-pound baby.” He added: “Then you see the baby all of a sudden start to change radically. I’ve seen it too many times. And then you hear that it doesn’t have an impact, right?”

In a Fox News interview from that month, Kennedy made similar false claims that vaccines are “exempt from pre-licensing controlled placebo trials.”

There is no evidence that childhood vaccines cause autism or other brain disorders in children. The original report from Andrew Wakefield that tried to link the measles vaccine to autism has been retracted .

Concerns raised by Kennedy about the vaccine preservative thimerosal have also been discredited , as its removal from vaccines in 2001 had no effect on the frequency of disease.

Furthermore, in many children with autism, studies of blood from mothers obtained during pregnancy, and from children on the day of birth, indicate that abnormalities are present before children receive a single vaccine.

Unfortunately, although the leaked video went viral, the science and public health benefits of vaccines have not.

Before the introduction of the measles vaccine in 1963, 3 to 4 million children in the U.S. were infected annually, resulting in approximately 48,000 hospitalizations, 1,000 cases of encephalitis and 400-500 deaths. In contrast, there were 58 known cases of measles in 2023. Only 5 percent of those cases were in people who had received the MMR vaccine on the recommended vaccine schedule.

The fight against mumps enjoyed similar success. Before the introduction of the mumps vaccine in 1967, up to 100,000 children in the U.S. were infected annually, accounting for 10 percent of non-bacterial meningitis and 36 percent of encephalitis. In 2023, the U.S. had only 436 cases.

The impact of the rubella vaccine is greater still. In one year in the mid-1960s, there were 12.5 million rubella cases. The exposure of unborn children resulted in deafness in 11,000, blindness in 3,500, intellectual disability in 1,800 and 2,100 neonatal deaths. In contrast, the number of annual rubella cases today is less than 10 per year .

The measles-mumps-rubella vaccine, popularly known as the MMR vaccine, which simultaneously protects children from all three viral diseases, was introduced in 1971. The other three-component vaccine given to children in the U.S. is diphtheria-tetanus-pertussis.

In the first decades of the 20th century, there were up to 200,000 diphtheria cases per year with a death rate of 5-10 percent . Since the adoption of DTP vaccine in the 1940s, the number of annual cases in the U.S. has dropped to the single digits.

Tetanus, also known as “lockjaw,” was uncommon in the U.S. even before the introduction of a vaccine, with 500 cases per year, but infection is almost always fatal. It remains a global threat, particularly to newborns. Neonatal tetanus claimed 1 million lives per year worldwide in the 1980s, and 14,000 lives in 2019.

Cases of whooping cough (pertussis) decreased from 270,000 per year in the U.S. to less than 4,000 with the introduction of the DTP vaccine. Like tetanus, it remains a global scourge, with more than 24 million cases per year globally, 160,000 of them fatal .

As recently as the 1950s, polio epidemics were common with more than 15,000 paralytic polio cases and close to 2,000 deaths each year. Most infected people had no or only mild illness; however, 5 percent had meningitis, and 1 percent became paralyzed.

Polio has been largely eradicated due to the worldwide distribution of vaccines in campaigns led by the World Health Organization, UNICEF and the Rotary Foundation. However, polio continues to threaten unvaccinated children in Afghanistan, Pakistan and Gaza .

As fewer children die or are debilitated due to measles, mumps, rubella, diphtheria, tetanus and polio, we tend to forget that this is the result of an evidence-based childhood vaccination program. Eliminating vaccines or changing the way they are given without evidence of equivalent efficacy would be a hazardous undertaking.

Children, not the adults who make those decisions, will pay the price.

W. Ian Lipkin MD is the John Snow Professor of Epidemiology and director of the Center for Infection and Immunity at the Mailman School of Public Health of Columbia University. Larry Brilliant MD is a physician, epidemiologist and founder and CEO of Pandefense Advisory. Lisa Danzig MD is an infectious disease specialist at Pandefense Advisory.

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