One of the questions some parents ask regarding vaccine safety is:  “Is it OK to give so many vaccines at one time?”  There are some parents who insist on giving their babies one shot at a time because they are afraid of challenging their young child’s immune system too soon.  Despite counseling parents that science does not support the “too many too soon” argument, some will nevertheless buck the standard of care and insist on bringing their children back to the office every week for the next shot. What they don’t realize is that by doing this, they are exposing their children to far, far, far more antigens in the form of bacteria and viruses, proteins, and polysaccharides, and chemicals and pollutants than they would have been had they received all the shots together at the same time.

So are we giving babies and children too many shots for their immune system to handle?   According to the Vaccine Education Center at the Children’s Hospital of Philadelphia, the answer is absolutely not:

Assuming the quantities of antibodies likely generated by an individual in 1 ml of blood (one-fifth of a teaspoon) during seven days after exposure to a vaccine, and the number of different specificities of those antibodies, then each infant would have the capacity to respond to about 10,000 vaccines at any one time. Using this estimate, one would predict that if 11 vaccines were given to infants at one time, then about 0.1 percent of the immune system would be “used up.”


Put another way:

The vaccines that children receive in the first two years of life are just a drop in the ocean when compared to the tens of thousands of environmental challenges that babies successfully manage every day.


To better illustrate what this “drop in the ocean” looks like, Jack Collins at Academic Earth sent me a link to an excellent video he helped create.  Click on the image below to see it:


Academic Earth has a number of excellent short videos, as well as full college lectures on numerous topics.  If you have some time, check it out.  And thanks to Jack Collins for shedding light on this common question and busting an all-too-persistent myth.