The following post first appeared on FactCheck.org.
Sen. Rand Paul gave false and misleading statements about vaccine safety in two separate interviews, including a claim that “many” children have developed “profound mental disorders” after vaccinations.
There is no evidence that any currently recommended vaccine causes brain damage or other mental disorders in otherwise healthy children. Severe reactions do occur but are extremely rare.
Vaccine safety has become a central topic in recent weeks as a measles outbreak that began at Disneyland in California has spread. Between Jan. 1 and Jan. 30, the Centers for Disease Control and Prevention reported that 102 people had confirmed cases of measles, a disease that the CDC declared “eliminated” from the United States in 2000 because of the highly effective vaccine. In recent years, a small but growing number of parents have avoided the measles, mumps and rubella vaccine because of fears related to debunked and fraudulent science.
Paul, Feb. 2: I have heard of many tragic cases of walking, talking, normal children who wound up with profound mental disorders after vaccines.
The senator’s office was unable to provide a single example of a vaccine causing a mental disorder; nor did his office provide any information on the specific type or types of mental disorders or vaccines that caused disorders to which Paul was referring. We contacted several experts on immunizations, however, and all of them agreed that there are no such links between common vaccines and mental disorders.
“The comments made by Rand Paul are worrisome, as they don’t seem to be based on scientific data,” said Marietta Vazquez, an associate professor of pediatrics at Yale University School of Medicine and a member of the U.S. Advisory Committee on Immunization Practices, a group convened by the CDC to advise on vaccines. “Indeed, there are no reported cases of profound mental disorders that I know of.”
There have been some reports of “lowered consciousness” or permanent brain damage after a vaccine is given for diphtheria, tetanus and pertussis (whooping cough) or measles, mumps, and rubella (MMR), but the CDC says that these are so rare that a cause-and-effect relationship cannot be determined.
The diseases these common vaccines prevent, on the other hand, can cause serious problems: One in 1,000 children with measles will develop a swelling of the brain “that can lead to convulsions and can leave the child deaf or mentally retarded,” and between 1 and 2 in 1,000 will die, according to the CDC. Pertussis is even more dangerous: One in 300 children with whooping cough will develop brain complications, and 1.6 percent will die.
Vazquez said in an email that serious adverse events can indeed occur with common vaccines, but they are exceptionally rare. Serious allergic reactions to the MMR vaccine, for example, occur at a rate of less than 1 in every 1 million doses, according to the CDC.
The modern anti-vaccination movement stems largely from a 1998 paper published in The Lancet that linked the MMR vaccine to the development of autism. The Lancet retracted that paper, and an investigation by the British Medical Journal found the work to be fraudulent. The paper’s author, Andrew Wakefield, had his medical license in the United Kingdom stripped.
More recently, Rep. Michele Bachmann spread further anti-vaccine sentiment by repeating a story about the vaccine for human papillomavirus, an infection that causes cervical cancer, and its theoretical link to “mental retardation.” We wrote in 2011 about that claim, which is entirely baseless.
The Institute of Medicine, an arm of the National Academy of Sciences, released a report in 2011 summarizing the safety of all vaccines the CDC recommends for children. There is sufficient evidence, the report said, to reject the link between MMR and autism, as well as a link between MMR and type 1 diabetes; between inactivated influenza vaccine and a facial nerve disorder known as Bell’s palsy; between the diphtheria, tetanus and whooping cough vaccine and type 1 diabetes; and between the inactivated influenza vaccine and exacerbation of asthma.
The report did find some links that are “convincing,” including several related to the varicella (chicken pox) vaccine and the chance of getting the virus itself from the vaccine. The MMR vaccine is also known to cause fever-related seizures, which the IOM noted “are generally benign and hold no long-term consequences,” and in very rare cases involving those with compromised immune systems (which is among the medical reasons for delaying or skipping some immunizations), the vaccine is known to cause a disease called measles inclusion body encephalitis. Six common vaccines can cause anaphylaxis, or severe allergic reaction. Several other links between vaccines and adverse events were found to be “generally suggestive,” though “not firm enough to be described as convincing.”
The vast bulk of reported problems (135 different links out of 158 studied) are so rare as to make it impossible to establish or reject a cause-and-effect relationship.
Institute of Medicine, August 2011: Vaccines offer the promise of protection against a variety of infectious diseases. Despite much media attention and strong opinions from many quarters, vaccines remain one of the greatest tools in the public health arsenal. Certainly, some vaccines result in adverse effects that must be acknowledged. But the latest evidence shows that few adverse effects are caused by the vaccines reviewed in this report.
James Cherry, a professor of pediatrics at the David Geffen School of Medicine at the University of California, Los Angeles, told us that some of the concerns about vaccines and brain damage actually extend further back, to the whooping cough vaccine administered in the early 1980s. There were claims that that vaccine was causing brain damage. Cherry published a review in the Journal of the American Medical Association in 1990 that cited several studies that found no such effects.
The modern pertussis immunization is included in one vaccine with tetanus and diphtheria, and the compound that was falsely linked to brain damage decades ago is no longer present, Cherry said. The CDC acknowledges that there have been reports of permanent brain damage, but notes that “[t]hese are so rare it is hard to tell if they are caused by the vaccine.”
Earlier on Feb. 2, Paul also appeared on Laura Ingraham’s radio show and spoke about vaccines.
Paul, Feb. 2: I was annoyed when my kids were born that they wanted them to take hepatitis B in the neonatal nursery, and it’s like, that’s a sexually transmitted disease, or a blood-borne disease, and I didn’t like them getting 10 vaccines at once, so I actually delayed my kids’ vaccines and had them staggered over time.
The hepatitis B vaccine is administered at birth because it can prevent transmission of the disease from mother to child. According to the CDC, hepatitis B infections in children have dropped 95 percent since 1990 as a direct result of that vaccine. As with other vaccines, the danger from hepatitis B immunizations is extremely low. Severe reactions occur in less than 1 in 1 million cases, and soreness and fever occur more frequently.
Furthermore, Paul’s contention that getting multiple vaccines at once could be risky is unfounded. Several studies have found that multiple vaccinations in a short period do not raise the risk of serious reactions.
For example, in 2013, a study published in the Journal of Pediatrics found that increasing exposure to the compounds found in vaccines does not raise the risk of autism spectrum disorders. Another study in Pediatrics in 2010 found that children vaccinated on time showed no adverse neuropsychological effects at 7 to 10 years of age compared with those whose vaccines were delayed; by some measures, the children vaccinated on time performed significantly better. One other study found that delaying the MMR vaccine actually increased the risk of seizures.
“It’s stupid,” said Cherry, referring to the idea of delaying and staggering immunizations. By delaying them, “that will allow these illnesses to occur. It’s no big deal when there’s nothing around and everybody is vaccinated, but it’s a big deal now” because of the measles outbreak.
On CNBC, Paul changed his claim of “10 vaccines at once” to “five and six,” which more accurately reflects the CDC immunization schedule. The hepatitis B vaccine is the only vaccine given at birth, with others following after a few months.
Public health officials have expressed concern that measles will reestablish a foothold in the U.S. In a press briefing on Jan. 29, U.S. Assistant Surgeon General Anne Schuchat noted that the 644 cases reported last year were the most in 20 years. Though it is relatively unfamiliar in this country, measles is still very common around the world, with about 20 million cases annually.
Schuchat, Jan. 29: In 2013, about 145,700 people died of measles across the world. … One in 12 children in the United States is not receiving their first dose of MMR on time.
She also noted that the MMR vaccine is safe, effective and “highly recommended.” But a small percentage of parents use religious and “philosophical” exemptions to avoid vaccinations; for example, in California, where the newest measles outbreak began, in the 2013-2014 school year, 17,253 children (3.1 percent of all children enrolled in kindergarten) received philosophical exemptions.
A spokesman from Paul’s office said in an email that the senator “believes that vaccines have saved lives, and should be administered to children. … He also believes many vaccines should be voluntary and like most medical decisions, between the doctor and the patient, not the government.”
– Dave Levitan