Chickenpox :
Chickenpox is an infection caused by the highly contagious varicella-zoster virus. It causes rashes with small blisters to erupt on the skin. These rashes appear 10 to 21 days after exposure to the virus. Besides the rashes and blisters, chickenpox can also cause fever, headache, tiredness, and a loss of appetite. A doctor can determine whether you have this infection with a simple look at the skin. Blood and skin tests can confirm the diagnosis. In most cases, the infection does not require any treatment. A doctor may prescribe medications to reduce itchiness and other symptoms. The symptoms usually subside by themselves within 10 days. In rare cases, the condition can cause severe symptoms like a high fever that does not reduce for days, breathlessness, shaking, confusion, coughing, and dizziness. Such symptoms require prompt medical attention.