First symptoms of smallpox infection usually appear within 10-12days after infection. The flu-like symptoms include:fever, fatigue, overall discomfort, headache, backache, diarrhea or vomiting or both. The next symptom:a rash appears in the next 2-3days, usually on the face and arms, then spreads all over the body. This later becomes pus-filled blisters, then scabs develop and usually fall off 3-4wks later leaving scars. People usually die during week2 of illness.
Attribution: Straight Talk Foundation