Brief Answer: It looks like a viral Infection. Detailed Answer: Hello, The history and the chronology of your symptoms suggests that you may be having either bacterial or viral infection. As your symptoms are vague with the involvement of the heart and appearance of the rash on the same day following the stomach flu, I would consider the following infections likely: 1. Rickettsial infection -This is a gram negative coccobacillus. The abdominal symptoms and the rash are typical of this but it should be confirmed by the lab investigation like ELISA for detection of antigen. 2.Coxsackie infection- This is a enterovirus, which can produce the symptoms of stomach flu, rashes and sporadic chest pain (Pericarditis). It should be confirmed by cell culture. 3.Cytomegalovirus infection - This is a herpes virus, which can also produce above mentioned symptoms and the chest pain because of myocarditis. It should be confirmed by detection of antibodies against the antigen by serological test. Besides these infection allergy related manifestations are the next likely causes. I would advice you to see a doctor who can order for the aforementioned tests after a physical examination. In the meanwhile drink plenty of fluids to stay hydrated. If you have any doubts feel free to post them. Thank you.

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