A woman complains of a severe pain in her throat on the left, difficult swallowing and mouth opening, elevated body temperature, and general malaise. The onset of the disease was 4 days ago after a case of tonsillitis. Examination detects a trismus of the masticatory muscles, the left tonsil is displaced toward the midline, the anterior palatal arch is infiltrated and protruding. The regional lymph nodes on the right are enlarged and painful on palpation. Make the diagnosis: