Compared to single-component vaccines, combination vaccines:

Compared to single-component vaccines, combination vaccines:

• A. are associated with significant incidence of adverse effects
• B. expose children to many more antigens than previous vaccines
• C. are more likely to overload an infant's immune system
• D. can be used if the child previously received component of the vaccine.

Answer: (D)

Combination vaccines deliver protection against several diseases in one shot, reducing the number of injections while providing the same overall protection. The immune system can handle multiple antigens at once, and the total exposure across the vaccination schedule isn’t greater than when giving the vaccines separately. A key practical point is that you can use a combination vaccine even if the child has already received one component of it; this allows you to complete or continue the series without restarting, following dosing intervals. This makes it easier to maintain protective immunity on schedule. The other statements don’t fit because combination vaccines are not associated with a meaningful increase in adverse effects, and they do not expose the child to substantially more antigens than the separate vaccines would.

Combination vaccines deliver protection against several diseases in one shot, reducing the number of injections while providing the same overall protection. The immune system can handle multiple antigens at once, and the total exposure across the vaccination schedule isn’t greater than when giving the vaccines separately. A key practical point is that you can use a combination vaccine even if the child has already received one component of it; this allows you to complete or continue the series without restarting, following dosing intervals. This makes it easier to maintain protective immunity on schedule. The other statements don’t fit because combination vaccines are not associated with a meaningful increase in adverse effects, and they do not expose the child to substantially more antigens than the separate vaccines would.