What Happens When Someone Has a Smallpox Infection

What Happens When Someone Has a Smallpox Infection?If a person becomes infected with smallpox, it may take anywhere from 7 to 17 days for symptoms to develop. At first a person may have flu-like symptoms such as high fever, fatigue, and headaches and backaches.
Within 2 to 3 days after a person starts to have symptoms, a rash develops. The rash usually affects the face, legs, and arms. It starts with red marks that become filled with pus and crust over. Scabs develop and then fall off after about 3 to 4 weeks.
Smallpox is very contagious from person to person, particularly during the first week a person has the rash. It is most commonly spread in infected drops of saliva when people cough or sneeze. A person is contagious until after all the scabs have fallen off.