We know by now that vaccines are unequivocally good. But as one myth regarding vaccines is disproven, another rises to take its place.

One of the most common concerns at the moment by parents when it comes to vaccinating their children is the suggestion that giving a young child a multiple number of vaccinations – either at the same time or within a short period of time – can overwhelm the immune system. To a parent who knows little about the subject, this can seem like a convincing worry.

There is plenty of research out there that shows this simply isn’t the case, and now a new study published in the Journal of the American Medical Association provides further evidence that this is not so. Children given multiple vaccines at a young age are not more likely to get ill than children who are not vaccinated.

“Some parents are concerned that multiple vaccines in early childhood could damage their child's immune system, making them more susceptible to future infections,” explains lead author Jason Glanz in a statement. “This new study suggests the theory of overloading an infant's immune system is highly unlikely.”

They looked at just under 1,000 children between the ages of two and four over a 12-year period. But rather than look at whether or not the children in the cohort who had been vaccinated were more or less likely to develop the diseases the vaccines were for, they looked specifically at the infections that children are not vaccinated against.

They found no significant differences in the rate of infections among kids who had been given cumulative vaccines and those who had not.

What the study found makes perfect sense. When a baby is born, they are exposed to a massive amount of new – and potentially harmful – microbes from the moment they leave the mother’s womb. Compared to this, the small amount of antigens found within the vaccines are minuscule, and would hardly even register to the developing immune system.

In fact, due to this veritable onslaught of bacteria, antigens, and other microorganisms that newborns are faced with in the first few years of life, the immune system is primed to function in exactly this environment, figuring out who is friend and who is foe.  

“Parents have genuine concerns about their children's safety as related to vaccination,” says Glanz. “We hope this study shines some light on their concerns, helping parents across the nation better understand the safety and benefits of vaccinating on time.”

So, please vaccinate your child if they have no medical reason why they shouldn’t be. It not only protects your own kid, but everyone else’s too.