A 35-year-old patient, a veterinarian, came to a dentist with complaints of chills, fatigue, fever up to 38°C, muscle pain, sensations of dryness, burning, and pain in the oral cavity, excessive salivation, vesicles in the interdigital folds, on the lips, oral and nasal mucosa. On examination of the oral cavity there were detected painful bright red erosions with polycyclic contours against the background of inflammation. The following was observed: scabs on the lips, enlarged tongue, impaired speech, salivation up to 4 liters per day. Make the diagnosis: