Varicella is caused by the varicella-zoster virus (VZV), which also causes shingles (herpes zoster). The virus typically affects children aged 2‒8 years.
Haemophilus influenzae type b (Hib) is an obligate human pathogen and an important cause of invasive bacterial infections in both children and adults, with the highest incidence among young children.
Varicella (chickenpox) is caused by the varicella-zoster virus (VZV), which also causes shingles. The virus spreads through the body into the skin causing rashes to appear.