The term herd immunity has been used for almost 100 years, since about 1923.
Other terms relating to herd immunity, like ‘hiding in the herd’ and ‘free-riding’ have come into use more recently.
Hiding in the Herd
Some people can get away with hiding in the herd.
Actually, they depend on it.
“Herd immunity is present in a community when such a high percentage of its members have been immunized from a particular disease that the disease cannot gain a foothold in the community. Thus, achieving and maintaining herd immunity protects not only those who have been vaccinated, but also those with compromised or weak immune systems, such as the elderly, babies, and those afflicted with HIV.”
Anthony Ciolli on Mandatory School Vaccinations: The Role of Tort Law
That’s because we don’t need 100% of people to be vaccinated and protected for herd immunity to work.

So people who are too young to be vaccinated or fully vaccinated, people who can’t be vaccinated because they were born with an immunodeficiency or get cancer and are on chemotherapy and other true medical exemptions, and even people who are vaccinated but their vaccine didn’t work, can still hope to be protected from vaccine preventable diseases because everyone around them is vaccinated.
These people still get the benefits of herd immunity. Even though they are unvaccinated and susceptible to getting a disease, they probably won’t, because most others in the herd are vaccinated and protected.
But it is not just those people with medical exemptions who try and hide in the herd.
“These numbers have led the National Vaccine Advisory Committee to conclude that religious and philosophical exemptions do not pose a threat to public health.”
T May on Free-riding, fairness and the rights of minority groups in exemption from mandatory childhood vaccination
And that was okay too for a while. It wasn’t that long ago that “free-riding” by those using philosophical or religious exemptions wasn’t a problem, because their numbers were small and herd immunity rates could still be maintained.
Can You Hide in the Herd?
Hiding in the herd can’t work for everyone though.
Surprisingly, Dr. Bob explains that well in his vaccine book that scares parents about toxins in vaccines, while reassuring them that it is okay to space out their child’s vaccines.
“I also warn them not to share their fears with their neighbors, because if too many people avoid the MMR, we’ll likely see the diseases increase significantly.”
Dr. Bob Sears in The Vaccine Book
Basically, if too many people are trying to hide in the herd and have skipped their vaccines, then we have a breakdown in herd immunity and we start to see the return of many vaccine-preventable diseases.
These aren’t people who can’t be vaccinated though.
They are people who refuse to be vaccinated and intentionally don’t vaccinate their kids.
“In other words, hide in the herd, but do not tell the herd you’re hiding; otherwise, outbreaks will ensue. Sears’ advice was prescient. Recent outbreaks of measles in 15 states, caused by an erosion of herd immunity in communities where parents had chosen not to vaccinate their children, were the largest in the United States since 1996.”
Dr. Paul Offit on The Problem With Dr Bob’s Alternative Vaccine Schedule
And that seems to be exactly what happened as more and more parents have walked into their pediatrician’s offices with a copy of Dr. Bob’s Alternative Vaccine Schedule.
While he predicted that it would “increase vaccination rates in our country,” as most others knew, they went down instead, and we continue to see more and more clusters of unvaccinated children.
Of course, Dr. Bob didn’t create the modern antivaccine-movement, but the bandwagoning effect he and other “thought influencers in the anti-vaccine movement” have on parents isn’t hard to see. Parents get scared by their anti-vaccine talking points and they go on to scare other parents into not vaccinating and protecting their own kids.
Tragically, the consequences of all of this was predictable too.
“If more parents insist on Sears’ vaccine schedules, then fewer children will be protected, with the inevitable consequence of continued or worsening outbreaks of vaccine-preventable diseases.”
Dr. Paul Offit on The Problem With Dr Bob’s Alternative Vaccine Schedule
More outbreaks of vaccine-preventable diseases.
What to Know About Hiding in the Herd
When too many people try and hide in the herd, it makes it hard to maintain necessary levels of herd immunity, which puts everyone, including medically fragile children and adults, at higher risk for getting a vaccine-preventable disease.
More About Hiding in the Herd
- Benefits vs Risks
- Community Immunity
- Herd Immunity
- Yes, herd immunity works
- Herd Immunity
- You can’t hide in the herd
- The Problem With Dr Bob’s Alternative Vaccine Schedule
- Rapid Emergence of Free-Riding Behavior in New Pediatric Immunization Programs
- One more time: Vaccine refusal endangers everyone, not just the unvaccinated
- Study – Vaccine Rejection and Hesitancy: A Review and Call to Action
- Study – Free-riding, fairness and the rights of minority groups in exemption from mandatory childhood vaccination.
- Study – The Roles of Altruism, Free Riding, and Bandwagoning in Vaccination Decisions
- Study – Mandatory School Vaccinations: The Role of Tort Law
- Evidence, herd immunity, and ‘total assholes’
- After all this time, Dr. Bob Sears finally tips his hand on vaccines, part IV
- Opting-Out Of Vaccines; Dipping Below Herd Immunity
- CDC – What Would Happen If We Stopped Vaccinations?
- Andrew Wakefield claims “natural Herd Immunity” is better than anything vaccines can do, never mind all that suffering
- Why Vaccinate?
- Why Should Vaccinated Individuals Worry About Measles Outbreaks?
- Endangering the Herd
- Measles Outbreak and Herd Immunity
- WHO – Vaccination greatly reduces disease, disability, death and inequity worldwide