By: Scott Campbell and Julian Ellis

vaccinationFlu season is upon us! You can bet that vaccine topics will keep popping up more and more in the newspaper, television and the internet. Unfortunately, many of these resources provide information that is not supported by scientific evidence.

Many people who are against the use of vaccines say “The majority of people who get diseases have been vaccinated.” We will work to explain how this statement is in fact a MYTH and how it can mislead patients into thinking that they no longer need to receive vaccines.

Myth 1: “The majority of people who get disease have been vaccinated”

Those against vaccines use this myth to argue that vaccines are ineffective. In one sense this myth is “true.” During an outbreak it is often the case that among those who become ill, people who have been vaccinated outnumbers those who have not. However, two simple factors can be used to explain this phenomenon, and show that this myth definitely does not prove that vaccines are ineffective.

Factor 1: No vaccine is 100% effective.

Factor 2: The number of people who receive a vaccine greatly outnumbers those who don’t get a vaccine.

To make this easier to understand, let’s use an example. Let’s say that there is a group of 1,000 people, and that 995 of them have received their measles vaccine. There is a measles outbreak in this town and the 5 patients who did not receive a vaccine become sick. Out of the 995 people who have received their vaccine, 7 of them become ill. Looking at these numbers in isolation, 7 out of 12 people or 58% of those who become ill have already had vaccines. Let’s take a closer look at this case, by reviewing the 2 factors outlined earlier.

Factor 1: No vaccine is 100% effective

– Most vaccines that you receive as a child are 85% to 95% effective. There will be a small number of patients for which the vaccine will not be fully effective. This explains why 7 people who had received vaccines still got measles.

Factor 2: The number of people who receive a vaccine greatly outnumbers those who didn’t get a vaccine     

– This factor explains why it “looks like” more people who had received a vaccine got sick. If you look at it in another way, the math begins to make more sense.

– Of those patients who didn’t receive the vaccine, 100% of them got sick. Of those patients who received the vaccine, less than 1% actually got sick.

– So you can see that the vaccine worked very well to prevent the illness in the vast majority of people who received the vaccine. If no one had received their vaccine, then probably closer to 100% of these 1,000 people would have become sick with measles.

Looking at a case like this closely, it is obvious that receiving vaccines is very important to minimize your risk of getting sick.

If you have any questions about the flu vaccine, or any other vaccine, contact your trusted pharmacy team at Canadian Compounding Pharmacy. Give us a call at 416-239-3566 or leave a comment below.


1. Centers for Disease Control and Prevention. Vaccines and Immunizations: Some Common Misconceptions. Accessed August 27, 2013