RESUMEN
A 21-year-old male with no any other diseases presented with fever, chills, and chest discomfort. A chest radiography scan and a transthoracic echocardiogram revealed a large amount of pericardial effusion. An H1N1 viral real-time PCR test confirmed the presence of H1N1 viral infection. Pericardiocentesis was performed to reduce symptoms, and oseltamivir (Tamiflu(TM)) was administered. His symptoms improved during the first 4 days, and there was no relapse of the pericardial effusion. The most common manifestation of influenza A infection is respiratory tract infection. Although a cardiovascular manifestation is possible, it is extremely rare. We have reported here a case of acute pericarditis with a large amount of pericardial effusion in a healthy adult infected with influenza A virus (H1N1, swine-origin).