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Posts for category: Immunizations

October 16, 2018
Category: Immunizations

Misinformation About the HPV Vaccine Keeps Vaccination Rates Low

The Overwhelming Safety of the HPV Vaccine

Paul A. Offit, MD

September 07, 2018

No vaccine has suffered more from misinformation and ill-founded concerns than the human papillomavirus (HPV) vaccine. Antivaccine activists have claimed that HPV vaccine causes chronic pain syndromes, chronic fatigue, sudden death, and a variety of autoimmune disorders. In addition, activists have gone so far as to claim that the HPV vaccine increases risky sexual behavior. These claims are often supported by the media as well as by substandard studies published in predatory journals. Indeed, on December 4, 2013, Katie Couric, in a segment titled "HPV Vaccine Controversy," interviewed two mothers: One claimed that the vaccine had caused her daughter to suffer chronic fatigue, the other that the vaccine had caused an otherwise unexplained death.

As a consequence of such fears, immunization rates for the HPV vaccine remain low. According to the Centers for Disease Control and Prevention (CDC), only 53% of girls and 44% of boys have received the recommended doses.[1] As currently constructed, the HPV vaccine—which contains the L1 surface protein from nine different strains—will prevent about 29,000 cases of HPV-associated cancers and 5000 deaths a year.[2] Unfortunately, because only about half of US adolescents have received this vaccine, every year about 15,000 people are destined to suffer and 2000 to die from a preventable cancer.

To the credit of the scientific and medical communities, millions of dollars have been spent on studies examining the safety of the HPV vaccine. Pre-licensure, about 30,000 people were studied for 7 years.[2] Post-licensure, more than 1 million people have been formally studied, examining all manner of chronic pain and fatigue syndromes as well as more than a dozen different rheumatologic diseases.[3,4,5,6] Not surprisingly, the HPV vaccine has not been found to cause any chronic or debilitating condition. Indeed, the HPV vaccine is probably the world's best-studied, modern-day vaccine.

Another Unwarranted Concern Debunked: Primary Ovarian Insufficiency

One concern recently raised by antivaccine activists is that the HPV vaccine causes primary ovarian insufficiency. How this concern was born remains a mystery. HPV doesn't infect the ovaries. And the HPV L1 surface protein doesn't mimic proteins on ovarian cells, which would at least make an autoimmune disease biologically plausible. Nonetheless, the fear persists. To address this concern, researchers at Kaiser Permanente Northwest examined a cohort of 199,078 female patients, finding 120 with a diagnosis of primary ovarian insufficiency.[7] The researchers found no statistically significant elevation of risk for ovarian failure following receipt of the HPV vaccine. They also didn't find an increased risk following receipt of the Tdap, MenACWY, or inactivated influenza vaccines.

The Kaiser Permanente study can now be added to the mountain of evidence that should reassure clinicians and parents that the HPV vaccine is safe. HPV, on the other hand, isn't safe. And until we dramatically increase immunization rates against this common, devastating infection, children will continue to suffer our ignorance.


Medscape Infectious Diseases © 2018 WebMD, LLC

June 10, 2018
Category: Immunizations


In this period of “alternate facts,” a 24-hour news cycle, and an internet that can provide whatever answer a person seeks, it can be difficult to convince parents and patients using facts alone. Parents may respond using their own “facts” leaving you frustrated and unprepared to dive further into the conversation.

Without further conversation and as more parents become convinced by the counter-arguments, these “alternative facts” become widely held “truths.” Often the counter-arguments are based on fallacies, or errors of logic or reasoning. Different types of logical fallacies have been described in an article by David Ferrer, published on The Best Schools website. The article, which includes some short video examples, describes 15 types of fallacies:

  • Ad hominem attacks — Criticizing the messenger in the absence of a counter-argument related to the fact being discussed.
  • Straw man attacks — Attacking a position or fact that was not actually put forth. For example, oversimplification of a complex subject or statement to make it appear false.
  • Appeal to ignorance — Taking advantage of what is not known. Using the notion that something has never been proven definitively is a common example of this type of fallacy.
  • False dichotomy — Making a position appear to have only one of two possible options when the options are not mutually exclusive or when more than two options exist.
  • Slippery slope — Arguing against a fact by suggesting unlikely, extreme outcomes.
  • Circular argument — Using the preliminary assumption as the basis for arriving at the same conclusion.
  • Hasty generalization — Jumping to conclusions without reviewing all available evidence.
  • Red herring — Using a parallel or seemingly relevant argument to distract from the original point being discussed.
  • Appeal to hypocrisy — Suggesting deception or insincerity of the messenger as a way to neutralize or distract from the issue.
  • Causal fallacy — Incorrectly identifying two things as causally associated either without enough evidence to do so (false cause); solely based on one occurring before the other (post hoc); or because they were found together (correlational fallacy).
  • Fallacy of sunk costs — Continuing with, or suggesting continuation of, a project based on the resources invested to date without consideration of future resources that will be incurred if the project continues.
  • Appeal to authority — Considering something to be true simply because a perceived authority said it is so (without evidence) or because it was said to be true by citing authority figures who are not qualified in that field.
  • Equivocation or ambiguity — Delivering a message that is intentionally deceitful or misleading.
  • Appeal to pity — Evoking emotion to deter or replace the discussion of facts.
  • Bandwagon approach — Suggesting something is true because it is a popular belief; it is accepted by authorities or large numbers of people; or because someone specific, based on their reputation, agrees.

Recognizing these fallacies, and helping your patients and families recognize them may be useful to approaching vaccine-related conversations as well as helping sort out fact from fiction in general. To that end, the VEC recently created a new Special Topics sheet, titled Logical Fallacies and Vaccines: What You Should Know. The new, four-page sheet includes a definition for each type of fallacy, a common example of how the fallacy is used to argue against vaccines, and a “reality check” statement about the related myth.

As with other Special Topics sheets, and most VEC materials, this information can be photocopied for distribution, linked from your website, or shared on social media.

May 26, 2018
Category: Immunizations

April 4, 2018 from the American Academy of Pediatrics

Here’s why it is important to follow the childhood immunization schedule

  • Parent Plus

Many of us have not experienced deadly or crippling diseases like measles, rubella and polio. These diseases are mostly gone now that children receive immunizations starting at birth.

Have you ever wondered how pediatricians know what vaccines your child should have and when?


Your pediatrician follows the Recommended Immunization Schedule for Children and Adolescents. The schedule is carefully reviewed, updated and approved each year by the American Academy of Pediatrics, the Centers for Disease Control and Prevention, and the American Academy of Family Physicians.

Following are answers to common questions about how vaccines keep children safe from illnesses that we now only read about in history books.

Q: How are the timing and spacing of shots determined?

A: Scientists study what age a child’s immune system will provide the most effective protection after receiving a vaccine. They also look at when infants, children and adolescents are at most risk for each disease.

Q: Why are three or more doses of some vaccines needed?

A: It depends on how long a vaccine provides protection. Some need to be given three or four times. They are spaced out over a period that gives children the best protection.

Q: Can shots be spread out over a longer period?

A: This would leave a child unprotected for a longer time. Young babies are more likely to get very sick from vaccine-preventable diseases. Vaccinating them as soon as possible following the recommended schedule works best with the child’s immune system.

Spreading out the shots has not been scientifically shown to be safer. There is no research to show that children have the same protection with a very different schedule.

Q: Does it overwhelm a child’s immune system to give multiple shots in one visit?

A: No. Infants and children are exposed to more germs every day just by playing, eating and breathing than what is in any combination of vaccines on the schedule.

Q: Where can I find the recommended immunization schedule?

A: Find a chart of vaccines and diseases they prevent at

Excerpted from, Learn about 14 diseases that are history, thanks to vaccines at

October 07, 2017
Category: Immunizations

Correcting Robert F. Kennedy Jr.’S Vaccine ‘Facts’


September 22, 2017Original Article  By Paul A Offit

When people misrepresent facts on the record, journalists are in a tough spot — especially when that information can be harmful.

Which brings me to STAT’s recent interview with Robert F. Kennedy Jr., conducted by Helen Branswell. STAT wanted to interview Kennedy about his claim in January 2017 that Donald Trump would soon appoint him to head a commission on vaccine safety and scientific integrity. Seven months had passed since Kennedy had made the claim and no announcement had been made. STAT wanted to find out where things stood.

Branswell began her interview by asking Kennedy eight different times and in eight different ways where things stood on his commission. Each time, he failed to confirm or deny whether the White House was about to appoint him.

That clearly wasn’t what Kennedy wanted to talk about. Instead, he wanted to talk about his belief that mercury in vaccines is poisoning America’s children and that no one in the federal government seems to care. By insisting that the interview be conducted in the question-and-answer format, Kennedy effectively tied STAT’s hands, which had to print what he said without editorial comment or opposing views.

I feel compelled to oppose Kennedy’s claims.

During the interview, Kennedy said that some babies were being injected with 25 micrograms of ethylmercury, which is part of a preservative called thimerosol that is used in multi-dose vials of influenza vaccine. He claimed that amount to be “100 times” greater than the amount considered to be safe.

As an environmentalist, Kennedy should know that mercury is a natural part of the Earth’s crust. As a consequence, methylmercury (environmental mercury) is contained in water and anything made from water, like breast milk and infant formula. The human body eliminates ethylmercury from vaccines far more efficiently than it eliminates naturally occurring methylmercury.

Babies typically ingest about 360 micrograms of methylmercury during the first 6 months of life, well before they will ever receive their first dose of influenza vaccine. If the 25 micrograms of ethylmercury in vaccines is 100 times greater than what Kennedy claimed is safe, then simply by living on Earth, by 6 months of age babies will have ingested an amount of mercury that is 1,440 times greater than Kennedy’s safety limit.

According to Kennedy’s calculations, all of us are massively intoxicated with mercury. The only way to avoid this would be to move to another planet.

Kennedy also said that he wanted to ensure “that vaccines are subject to the same kind of safety scrutiny and safety testing that other drugs are subject to.” In fact, vaccines are subjected to greater scrutiny than drugs. Much greater. For example, the CDC spends tens of millions of dollars every year on the Vaccine Safety Datalink, a system of linked computerized medical records from several major health maintenance organizations that represents about 7 million Americans, 500,000 of whom are children. Nothing like this exists on the drug side. Frankly, if a Drug Safety Datalink existed, the problem with Vioxx as a cause of heart attacks might have been picked up much sooner.

Kennedy said, “We need to, prior to licensing vaccines, do gold standard safety testing, like every other drug approval requires. We need to do double-blind placebo testing.” Branswell knew that the FDA does require placebo-controlled trials before licensure. So she pushed back. “Sir, that’s done all the time,” she said. “That is done all the time.”

Branswell was right. Here’s an example of the kind of testing that vaccines are put through. One of the currently licensed vaccines against rotavirus was tested in a placebo-controlled, prospective, 11-country, four-year trial of more than 70,000 infants before being approved. That’s fairly typical of most pre-licensure trials. But STAT was stuck having to report Kennedy’s remarks as is, even though Branswell knew they were false. That was the deal. The interview had to be printed without contradiction.

Perhaps most outrageous was Kennedy’s claim that “the hepatitis B vaccines that are currently approved had fewer than five days of safety testing. That means that if the child has a seizure on the sixth day, it’s never seen. If the child dies, it’s never seen.” Safety monitoring for the hepatitis B vaccine, like all vaccines tested before being licensed, involved determining side effects in the vaccinated and unvaccinated group for weeks after each dose. Indeed, some subsets of vaccinated individuals have been monitored for 30 years after hepatitis B vaccination.

Throughout the interview, Kennedy never adequately addressed the new commission. Creating such a commission doesn’t make sense to me for two main reasons.

First, a vaccine safety commission already exists. It’s called the Centers for Disease Control and Prevention. Staffed by epidemiologists, microbiologists, virologists, statisticians, molecular biologists, and clinicians, the CDC supervises the Vaccine Safety Datalink, which I described earlier. Whenever a new vaccine is licensed, this system quickly determines who’s been vaccinated and who hasn’t and detects any side effects that might be occurring more frequently in the vaccinated group.

Second, a commission for scientific integrity also already exists. Independent of the CDC, it’s called the Office for Research Integrity, and is housed in the Department of Health and Human Services.

It’s unfortunate that our culture, and our media, sometimes give celebrities a chance to comment without opposition on subjects about which they are often misinformed. It’s invariably the listener or reader who suffers this advice. Maybe journalists could at the very least add a cigarette-style caution to interviews like the one that STAT did with Robert F. Kennedy, Jr. Something like “CAUTION: Reading this article might be dangerous to your health.”

Paul A. Offit, M.D., is a professor of pediatrics and director of the Vaccine Education Center at the Children’s Hospital of Philadelphia. His most recent book is “Pandora’s Lab: Seven Stories of Science Gone Wrong” (National Geographic Press, April 2017).

September 08, 2017
Category: Immunizations
Tags: immunizations   Vaccines   Information   parents   AAP  

Information for Parents about Immunizations

Visit, the AAP parenting website, for information for families about immunizations. Always updated and evidence based.
Dr. T