The purified protein derivative (PPD) skin test (Mantoux test) is used to screen for which infection?

The PPD (Mantoux) skin test screens for prior exposure to/infection with Mycobacterium tuberculosis, by measuring a delayed-type hypersensitivity skin reaction to injected tuberculin protein. A positive result indicates TB exposure/infection (latent or active) but does not by itself distinguish between latent and active disease, which requires further evaluation (chest X-ray, sputum testing, symptoms assessment).