Vaccine overload is a nonmedical term. It refers to the notion that giving a child many vaccines at one time or weakens their immune system. The concept of vaccine overload is flawed in many ways despite the increase in the number of vaccines over recent years; improvements in vaccine design have reduced the immunologic load from vaccines.
Studies have revealed that there is no correlation to vaccines and illnesses that are often said to be correlated with them. Any experiment based on withholding vaccines from children has been considered unethical in recent years. The concept of vaccine overload is biological, not plausible. The notion of this is dismissed because of the evidence that proves otherwise.
Vaccine overload is a very real thing that is not discussed often enough. It is, in essence, the giving of multiple vaccinations to a child that encompasses different diseases. But, it also increases the risk of harmful side effects because it can overload the immune system. It is especially harmful to children who are vulnerable to illnesses or whose systems are already compromised, even by something as simple as the fact that they are coming down with a cold or flu or have one already.