Myocarditis is an inflammatory heart disease, commonly caused by viral infections, with the Coxsackievirus being the most common. Other infections, such as bacterial, fungal, and Rickettsia, can also cause myocarditis. These infectious myocarditis cases generally show preliminary symptoms of infection, such as fever, in the 1 to 3 weeks before the onset of the disease. Fever indicates a high body temperature, which means the same as having a fever. However, there are also non-infectious forms of myocarditis, such as those caused by drugs, radiation, or connective tissue diseases, and these non-infectious types of myocarditis do not always involve a fever.