The Incredible Capacity Of The Immune System
By age two, infants in the US can receive up to 20 vaccinations. In view of that, concerns had been raised that too many immunizations could overwhelm an infant's immune system.
However, infants are bombarded with germs every day in the air they breathe and the food they eat, but their immune systems are able to handle these exposures. Vaccination does not overburden a child's immune system; rather, it strengthens even the young infant's developing immune system.
The vaccines that are recommended for all children use only a small portion of the immune system's 'memory.' Scientists estimated that based on the immune system's capacity to respond, a child could theoretically get 10,000 vaccines in one day and still not 'use up' his or her immune response or ability to respond. Although more vaccines are recommended for children today than in the past, children are actually exposed to fewer antigens (the substances that produce an immune response) in vaccines than ever before due to advances in chemistry and vaccine production technology.