Patients who are being treated with penicillin for a syphilis infection are considered:

A. communicable for the rest of their life.
B. noncommunicable in about 4 weeks.
C. noncommunicable within 28 to 48 hours.
D. noncommunicable right from the initial infection.

Answer: C. noncommunicable within 28 to 48 hours.