Current research suggests that the lack of selenium results in a more virulent strain of the coxsackievirus becoming the dominant viral species present in the population of virus, but the mechanism of this selection event is unclear.
Some signs and symptoms of acute Keshan disease include dizziness, malaise, nausea, chills, loss of appetite, projectile vomiting, pallor, low arterial blood pressure (less than 80/60 mmHg), dyspnea, precardiac (anterior to the heart) or substernal (behind or below the sternum) discomfort, cardiogenic shock, and constricted veins in one's extremities.
Some signs and symptoms of subacute Keshan disease include malaise, restlessness, gallop rhythm, facial edema, heart dilation, and cardiac shock.
Some signs and symptoms of chronic Keshan disease include palpitations, dyspnea, cough (with blood), pain in one's right upper quadrant, edema, oliguria, enlargement of the heart, systolic murmur, gallop rhythm, and hepatomegaly.
An individual will have to be monitored once they begin to take the selenium supplements, due to the fact that too much of it can cause balding, intestinal distress, weakness, and slow mental functioning.