Vaccines and Herd Immunity: What You Need to Know

Vaccines and Herd Immunity: What You Need to Know

Protect your kids and yourself by staying informed.

Outbreaks of vaccination-controllable diseases are spreading.

When the number of measles cases hit 30 in Clark Country, Washington, in December 2019, the governor declared a state of emergency. The disease, which threatens brain function and life itself, was then reported in Oregon, Vancouver, and King County, Washington. At the same time, on the other side of the country, The New York Times reported that a measles outbreak had affected more than 200 people in ultra-Orthodox Jewish communities in New York and New Jersey. On both coasts, the numbers are expected to get a lot worse before they get better.

In Clark Country, 7.9 percent of children were exempt from vaccines required for kindergarten entry, including the measles vaccine, which the CDC says is 97 percent effective. Only 1.2 percent of those exemptions were for medical reasons.

It’s estimated, says The Times, that more than 40 percent of the New York and New Jersey children who contracted measles were not vaccinated and the numbers could be much higher.

These episodes come on the heels of last year’s startling measles outbreak in California, Missouri and 19 other states. And a new study in JAMA says, “although measles vaccination has saved more than 21 million lives since 2000, reported measles cases increased worldwide by 31 percent from 2016 to 2017 in large part because of falling vaccination coverage...”

Here in the states, outbreaks of vaccination-preventable diseases can be attributed to non-immunization or under-immunization of both kids and adults and unimmunized folks who travel to and from countries across the globe where these diseases are wide-spread. All 50 states do require specified vaccines for public school students. Exemptions for medical reasons are universal, and almost all states grant religious exemptions. However, at this time, 18 states also permit exemptions for philosophical beliefs.

Since 2009, the proportion of children missing recommended vaccinations has climbed in Arkansas, Arizona, Idaho, Maine, Minnesota, Missouri, North Dakota, Ohio, Oklahoma, Oregon, Texas and Utah. Seattle, Tacoma, Portland and Salt Lake City are some of the urban areas with the greatest number of exempt kids.

Only Mississippi, California and West Virginia ban all nonmedical exemptions for kids in school—Maine may become the fourth. What’s the result of this ban? Mississippi, California and West Virginia have the highest MMR (measles, mumps and rubella) vaccination rates and lowest incidence of vaccine-preventable diseases.

What are the diseases that vaccinations protect against? They include chickenpox, diphtheria, flu, hepatitis A, hepatitis B, HIB (Haemophilus Influenzae type B), HPV (human papillomavirus), measles, meningococcal, mumps, pneumococcal, polio, rotavirus, rubella (German measles), shingles, tetanus and whooping cough (pertussis). Also preventable are anthrax, Japanese encephalitis, rabies, smallpox, tuberculosis, typhoid fever and yellow fever—but you get those shots only when the need arises.

The World Health Organization says while vaccines prevent two to three million deaths annually, another 1.5 million vaccine-preventable deaths could be avoided every year. They cite “complacency, inconvenience in accessing vaccines and lack of confidence” as being among the top reasons people choose not to vaccinate.

What about risks?
If you’re concerned about negative side effects from vaccines, check out the CDCs listing of all mild, moderate and severe reactions to each inoculation at:; search for “Possible side effects from vaccinations.” We interviewed over 150 experts on every side of the issue and read every available peer-reviewed paper; we calculated the risk of vaccination and found the benefits outweigh the risks 40,000 to one!

Bottom line
Get informed and protect your kids and yourself (adult vaccinations are also important), as well as your neighbor who might have a medical reason for not being vaccinated. You help create what’s called herd immunity, protecting those who cannot be vaccinated. That could be someone going through chemotherapy or suffering from an immune system-compromising disease.

Just because we no longer see the devastation that these diseases once caused, that’s no reason to doubt the protection vaccines can offer.

Medically reviewed in January 2020.

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