Can vaccines overwhelm a child's immune system?

Vaccines are meant to boost the immune system, enabling it to be able to recognize an infection. Once the immune system is ready it will aid in defending the person against the disease. Only in rare instances when the immune system is severely compromised can it be overwhelmed by a vaccine, and this would only occur if the vaccine contained live viruses.

It is unlikely that the few antigens (substances that evoke an immune response) in a vaccine would harm a child, given the usual number of foreign antigens that the child is exposed to normally. For example, the child who gets an upper-respiratory viral infection is exposed to 4 to 10 antigens, and a case of "strep throat" represents 25 to 50 antigens. The Institute of Medicine has said that in the face of these normal events, it seems unlikely that the number of antigens in childhood vaccines would be an appreciable burden to the immune system.

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Vaccines & Immunizations

Vaccines & Immunizations

Vaccines are commonly given to children in the form of a shot to help prevent serious diseases like measles and mumps. Vaccines are developed using either dead strains of a disease, weakened strains, or strains of a different dise...

ase. As adults, we receive flu vaccines or may need a booster of childhood vaccines to retain immunity. Travelers may receive vaccines either as a condition of entry to a country, or on recommendation of health officials. Generally there is little or no reaction to a vaccine, but in some cases the vaccine may cause an allergic reaction or a temporary, mild illness. Some vaccines are not safe for pregnant women, so it’s important to check with a healthcare professional.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.