Dr. Mom blog explores Everything you Need to Know About the Flu, the Flu Shot, and Common Myths

Previously I wrote a post about vaccines and autism that was very popular on life of dr. mom. Since then i’ve received hundreds of emails asking about vaccines, and I thought it might be helpful to clarify why people who are pro-vaccination have such strong opinions against those who make the decision not to vaccinate (aka anti-vaxxers).

Infectious diseases are making a comeback due to the anti-vaccination movement.  

Measles, mumps, and pertussis, just to name a few.

The United States experienced a record number of measles cases in 2015 (667 cases to be exact) which is shocking considering the United States was declared “measles free” in 2000.  In 2015, a single case of measles that started in a California amusement park spread to over 300 people.  Sadly, many of the people affected were also individuals who WERE vaccinated against the measles.

In my medical practice, and even in my own family, I notice that most people believe that the benefits of vaccination begin and end with the individual. But in fact, vaccines work via the power of the community.  This is why measles is making a comeback.

Even if YOU have been vaccinated, YOU are still at risk of these diseases because your neighbour or a child at your kid’s school might not be.  

Vaccines work very well to prevent deadly illnesses, but only if EVERYBODY (who can) gets them.

Vaccines do not just affect you as a person, they affect the community. Imagine a large boat manned by 100 sailors.  The boat has 100 holes in it, which are rapidly filling with water. Each sailor on the boat has access to one plug to stop the water from sinking the boat.   90 sailors \rush to plug the holes up, while the other 10 sailors don’t believe in plugs, or that the plugs will hurt their fingers so they don’t want to use them.  The result, is that 10 of the holes remain unplugged. The water seeps into the boat (albeit slower because the other 90 holes are plugged) and eventually, the boat fills with water and sinks.  

Everybody in the boat is affected by the decision of those 10 sailors to not plug up the holes.

People ask me “Why do I need to get vaccinated? I don’t know anyone who has ever had polio.”  Polio is a very debilitating and deadly disease that can paralyze people and cause death by paralyzing the breathing muscles.  No cure exists for polio, but in the 1950’s a vaccine was developed and used around the world. The effective use of the vaccine lead to almost complete eradication of the disease in the first world by 1970.  BUT – the developing world had limited access to the polio vaccination at this time, and in 1988 there were over 350,000 documented cases of polio. This epidemic lead to the “Global Polio Eradication Initiative” to prevent the spread of polio by getting everybody vaccinated.

Vaccines WORK.  

In 2018, there were only 29 reported cases of polio. In fact, polio is very close to being eradicated thanks to vaccines – but the anti-vaxxer movement is threatening this every day.

I hope the analogy helped those of you who aren’t 100% sure how vaccines work — I know I didn’t have a great grasp on it until medical school. Everyone’s choices affect not only themselves, but each other too.

Here are some statistics about vaccinations, in case you haven’t been convinced by now:

  • Vaccine refusal increases the risk of vaccine-preventable diseases among unvaccinated individuals
  • Unvaccinated children have a greater risk of acquiring vaccine-preventable disease than children who are vaccinated.  For varicella, this risk is 9x higher. For measles, this risk is 35x higher. For pertussis, this risk is 6-28 times higher.
  • Generally speaking, vaccine-preventable diseases such as measles, pertussis, etc. are more severe in infants and young children than in older children and adults.  This is because the younger the body, the more it is developing, and the more it can be affected by a disease.
  • Delaying immunizations until a child is older increases the time in which a child is vulnerable to vaccine-preventable illnesses, putting children at increased risk.

A systematic review looked at the association between vaccine refusal and the measles infection in the United States between 2000 and 2015.   

This study found: 

  • There were 1416 documented cases of the measles
  • Of these cases:
    • 57% had no history of measles vaccination.  71% of these people were unvaccinated despite being able bodied and old enough for vaccination (aka: vaccine refusal)
    • 14% had been vaccinated for the measles
    • 29% did not know or had unreported vaccination history
  • Vaccine refusal increases the risk of outbreaks of vaccine-preventable diseases in the general population (this includes those people who DO get vaccinated).
  • Unvaccinated individuals tend to cluster amongst one another, so some communities that have a strong “anti-vaxxer” movement are more vulnerable.
  • Outbreaks affect both individuals who are able bodied but refuse vaccines for religious of philosophical reasons, just as much as they affected children who are too young to be vaccinated, as well as people who have medical reasons for why they can not get vaccinated.
  •  The rates of disease among vaccinated individuals increase as vaccinated and unvaccinated individuals mix in communities.

I know some parents are still on the fence about vaccinations, but they are incredibly safe, and they protect our communities from debilitating and deadly diseases. If you have the opportunity to get vaccinated, please think about your community.

More from Dr. Mom


1.     Davis MM. Toward High-Reliability Vaccination Efforts in the United States. JAMA 2016; 315:1115.

2.     Glanz JM, McClure DL, Magid DJ, et al. Parental refusal of varicella vaccination and the associated risk of varicella infection in children. Arch Pediatr Adolesc Med 2010; 164:66.

3.     Glanz JM, McClure DL, Magid DJ, et al. Parental refusal of pertussis vaccination is associated with an increased risk of pertussis infection in children. Pediatrics 2009; 123:1446.

4.     Feikin DR, Lezotte DC, Hamman RF, et al. Individual and community risks of measles and pertussis associated with personal exemptions to immunization. JAMA 2000; 284:3145.

5.     Salmon DA, Haber M, Gangarosa EJ, et al. Health consequences of religious and philosophical exemptions from immunization laws: individual and societal risk of measles. JAMA 1999; 282:47.

6.     Glanz JM, Narwaney KJ, Newcomer SR, et al. Association between undervaccination with diphtheria, tetanus toxoids, and acellular pertussis (DTaP) vaccine and risk of pertussis infection in children 3 to 36 months of age. JAMA Pediatr 2013; 167:1060.

7.     Williamson G, Ahmed B, Kumar PS, et al. Vaccine-Preventable Diseases Requiring Hospitalization. Pediatrics 2017; 140.

8.     Robison SG, Liko J. The Timing of Pertussis Cases in Unvaccinated Children in an Outbreak Year: Oregon 2012. J Pediatr 2017; 183:159.

9.     Rosen JB, Arciuolo RJ, Khawja AM, et al. Public Health Consequences of a 2013 Measles Outbreak in New York City. JAMA Pediatr 2018; 172:811.

10.   Schwartz JL. Costs, Consequences, and Policy Responses of Vaccine-Preventable Disease Outbreaks. JAMA Pediatr 2018; 172:805.

11.   Salmon DA, Dudley MZ, Glanz JM, Omer SB. Vaccine hesitancy: Causes, consequences, and a call to action. Vaccine 2015; 33 Suppl 4:D66.

12.   Lieu TA, Ray GT, Klein NP, et al. Geographic clusters in underimmunization and vaccine refusal. Pediatrics 2015; 135:280.

13.   Gastañaduy PA, Budd J, Fisher N, et al. A Measles Outbreak in an Underimmunized Amish Community in Ohio. N Engl J Med 2016; 375:1343.

14.   Aloe C, Kulldorff M, Bloom BR. Geospatial analysis of nonmedical vaccine exemptions and pertussis outbreaks in the United States. Proc Natl Acad Sci U S A 2017; 114:7101.

15.   McBrien J, Murphy J, Gill D, et al. Measles outbreak in Dublin, 2000. Pediatr Infect Dis J 2003; 22:580.

16.   Hopkins Tanne J. Measles: two US outbreaks are blamed on low vaccination rates. BMJ 2019; 364:l312.


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