<s>[INST] My 39 year old brother in law has been in the hospital for 3 days now with what they are calling viral endocarditis.  He has fluid around his heart and is requiring oxygen to help him breath.  He is currently getting lasix every 8 hours.  He had several ECHO's which also showed  his heart was enlarged.  He is not on any antibiotics which I am assuming is because they suspect it is viral.  Is this a common occurance in such a young person? [/INST] Hi ThereI understand your concern and i would like to tell you that BACTERIAL ENDOCARDITIS is more common as compared to VIRAL ENDOCARDITIS. It can happen following a viral respiratory track infection. Yes antibiotics is not required in most viral etiologies only supportive therapy is needed. Don't worry he will be fine within few days.I Wish him good health </s>