Which of the following statements about smallpox skin lesions is correct?

Which of the following statements about smallpox skin lesions is correct?

• A. They appear as vesicles that crust quickly
• B. They crust and resolve in days
• C. They are identical in development
• D. They vary in development stages

Answer: (C)

Smallpox lesions move through the same sequence at roughly the same time across the entire body. Each lesion progresses in lockstep from macule to papule to vesicle to pustule and then to crust, so they appear at uniform stages rather than at different times. This synchronized development is why the statement that lesions are identical in development is the best choice. The other ideas don’t fit because crusting isn’t rapid and simultaneous for all lesions, and lesions don’t all resolve in a few days. Nor do the lesions vary widely in their stage of development at the same time. The key takeaway is the uniform progression of the rash, which helps distinguish smallpox from conditions where lesions appear at mixed stages.

Smallpox lesions move through the same sequence at roughly the same time across the entire body. Each lesion progresses in lockstep from macule to papule to vesicle to pustule and then to crust, so they appear at uniform stages rather than at different times. This synchronized development is why the statement that lesions are identical in development is the best choice.

The other ideas don’t fit because crusting isn’t rapid and simultaneous for all lesions, and lesions don’t all resolve in a few days. Nor do the lesions vary widely in their stage of development at the same time. The key takeaway is the uniform progression of the rash, which helps distinguish smallpox from conditions where lesions appear at mixed stages.