Severe or fatal disease is more likely in the following: Adults Patients with depressed T-cell immunity (eg, lymphoreticular cancer) Those receiving corticosteroids or chemotherapy or who are otherwise immunosuppressed Patients being treated with tumor necrosis factor (TNF) antagonists Treatment of Chickenpox Symptomatic treatment Sometimes oral antiviral agents IV acyclovir for immunocompromised patients and others at risk of severe disease Mild cases of chickenpox in children require only symptomatic treatment.