system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are the Chickenpox potentially fatal to adults, but almost harmless to children?
gpt
Although the rates for morbidity from varicella (Chicken Pox) are higher among adults, the seriousness of this is overblown.  

Yes, adults are at a higher risk of developing complications from varicella (such as pneumonia, especially if they smoke) but most adults will make a full recovery after a course of antiviral therapy (ex. Acyclovir 3200 mg/day for 5 days).  This is especially the case if treatment is initiated early, within 24 hours of the rash onset.

The individuals who are really at risk are immunocompromised individuals (HIV/AIDS patients) and pregnant patients

TL;DR Chicken Pox is still a relatively benign disease in healthy adults, just get that rash checked out within the first 24-72 hours and you'll be fine.