Final answer:
A kindergartener with impetigo can return to school 24 hours after initiating effective antimicrobial therapy, as the risk of spreading the infection is significantly reduced.
Step-by-step explanation:
In the context of a kindergartener with impetigo, it is generally advised that the student can return to school 24 hours after initiating effective antimicrobial therapy. Impetigo is a highly contagious skin infection caused by bacteria, and it is important for the child to be on antibiotic treatment prior to returning to school to prevent the spread to other children. This aligns with recommendations for bacterial infections where rapid-response antibiotics are used to manage the infection.
Since impetigo can be treated with antibiotics, once effective antimicrobial therapy has started and an adequate amount of time has passed (24 hours), the risk of transmission is significantly decreased. Therefore, option A. 24 is the correct answer to when a kindergartener with impetigo can return to school.