The acute phase last for the first few weeks or months of infection . It usually occur unnoticed because it is symptom @-@ free or exhibits only mild symptoms that are not unique to Chagas disease . These can include fever , fatigue , body aches , muscle pain , headache , rash , loss of appetite , diarrhea , nausea , and vomiting . The signs on physical examination can include mild enlargement of the liver or spleen , swollen glands , and local swelling ( a chagoma ) where the parasite entered the body .