A laboratory technician has a 10.5 mm area of redness and in…

A laboratory technician has a 10.5 mm area of redness and induration in his left forearm after getting a Mantoux test 48 hours before from the employee health nurse. The Mantoux test done by the same nurse 12 months ago was at 5 mm of induration. The technician denies cough, night sweats, and weight loss. Which of the following is a true statement?