I have a patient who had abdominal pain and loose stools for 3 weeks.travelled from pakistan 10 year old.stool routine analysis ,urine analysis and ultrasound were normal.treated with metronidazolefor 7 days and he improved but after 5 days now he came now with 4 days of fever ,cough,loose motions,vomitting and abdominal pain.got his blood analysis done.CBC, CRP ,-normal.BUN-5,creat-normal,but SGPT-1820 raised.widal,blood cultureand urine analysis awaited.what should be the differentials