Objective: To determine the epidemiology of varicella-zoster virus (VZ
V) infection in Australia using currently available data sources. Desi
gn: Analysis of national death data (23 years), congenital and neonata
l cases (one year) and attendances at sentinel general practices (two
years); hospital admissions in NSW and SA (six years); serological stu
dies in 1995 involving antenatal clinics in Sydney and Brisbane and ch
ild-care centre staff and refugees in Sydney: and case-ascertainment i
n 1995 in South Western Sydney among public hospital staff, childcare
centre staff and the community. Results: In Australia, there have been
an average of 3.5 deaths from chickenpox (mostly children) and 11 fro
m herpes zoster (mostly older people) each year since 1980. The crude
death rate for chickenpox has declined (p>0.05). In 1995, there were 1
4 cases of neonatal and two of congenital varicella. Average annual ad
mission rates for NSW and SA showed 1,200 hospital bed-days used for c
hickenpox, more than 20% with complications, and more that 7,300 bed d
ays for zoster; annually more that 880 in-patient admissions were comp
licated by VZV. Most people encounter the virus in their first 15 year
s, but some remain susceptible into their 20s; 25% of cases and 37% of
hospital admissions for chickenpox occur in people greater than or eq
ual to 15 years of age. Conclusion: VZV infection involves people of a
ll ages. It causes substantial morbidity and mortality, particularly a
t the extremes of life. The death rate from chickenpox but not zoster
has fallen since the introduction of acyclovir in the 1980s. Surveilla
nce of VZV infection must be given priority once vaccines become avail
able, to monitor changes in morbidity and mortality.