Highly sensitive and specific qualitative molecular test using Real-Time Polymerase Chain Reaction (Real-Time PCR) technique to detect DNA of Herpes Simplex Virus Type 1 (HSV-1). Performed on samples from infection site (vesicle fluid, ulcer swab, oral/pharyngeal swab, or body fluids like CSF). Gold standard for diagnosing active infection due to ability to detect virus even without clear symptoms or with small viral amounts.