Which of the following is a sign of an active MRSA infection?

The presence of signs of infection indicates that an individual has an active MRSA (Methicillin-resistant Staphylococcus aureus) infection. Symptoms such as redness, swelling, warmth, and the presence of pus or drainage are common indicators of an infection. MRSA can cause a variety of infections, ranging from mild skin infections to more severe invasive infections, which are often accompanied by noticeable physical symptoms.

The other options reflect conditions that do not indicate an active MRSA infection. The absence of pain, for instance, does not align with the typical symptomatology of an infection where pain is usually present. An asymptomatic condition suggests that there are no visible signs or symptoms, indicating the absence of an infection. Immediate recovery would imply that no infection existed or that it has been resolved swiftly, which contradicts the active nature of the MRSA infection being referred to in the question.