Abstract
A 34-year-old man with no medical history presented to our hospital with a sore throat and difficult oral intake for two days before admission. He had various symptoms, including red eyes, ocular discharge, a fever, and intraoral ulcers, and he was admitted immediately. The polymerase chain reaction test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was positive, as was the adenovirus antigen test of the pharyngeal swab fluid, suggesting overlapping adenovirus and SARS-CoV-2 infections. The patient's condition improved with conservative treatment. This case of severe and varied symptoms caused by co-infection with adenovirus and SARS-CoV-2 has been previously reported.