Flu-like symptoms start to develop a day or two before an itchy red rash appears. Fatigue, mild headache, fever, chills, and muscle or joint aches are typical. The rash emerges as raised red bumps that turn to teardrop-shaped blisters that are extremely itchy.
These blisters may appear anywhere on the body, usually starting on the face, trunk or torso, then spreading to the arms and legs. In some cases, the rash may even spread across your entire body, including areas such as the throat, mouth, and vagina.
The blisters come in waves, with new crops developing as old ones burst. New blisters stop forming within about 5 days. By the sixth day, most blisters will have burst, dried, and crusted over. Within 3 weeks of blisters appearing, most of the scabs will have disappeared.
Children usually have a much milder infection and recover faster than adults. Babies, adults, and those with weakened immune systems tend to have more severe and longer-lasting symptoms. They are at higher risk of developing complications, including inflammation of the brain (encephalitis) and pneumonia.
Newborns whose mothers develop chickenpox during early pregnancy are at risk for low birth weight and birth defects. If the mother develops chickenpox a week before birth, the newborn is at risk for a life-threatening infection.
Children who have had the chickenpox vaccine can still get chickenpox. However, they usually have a much milder case with a smaller number of blisters.
Cellulitis (a skin infection from bacteria) is by far the most common complication in children. It may leave scarring, especially if the child scratches the lesions. Necrotizing fasciitis ("flesh-eating disease") in children, though extremely rare, can occur as a complication of infection entering through the chickenpox lesions. Chickenpox blisters that appear in the mouth, throat, or anus are very uncomfortable. If the rash appears near the eyes, consult your doctor.
Like many viruses, the varicella-zoster virus is never completely gone once it has entered your body. Anyone who's had chickenpox carries dormant viruses in the roots of their nerve cells. These can sometimes reappear years later as shingles, a painful skin rash that affects a particular area of skin.
Shingles can appear at times of emotional stress, or when the immune system is low. It's not always known what has provoked the virus to come out of hiding. It's important to know that the shingles rash can transmit chickenpox. People who have already had chickenpox are immune, but people who haven't can get the virus from someone with shingles.