Secular trends in hepatitis A virus infection among Alaska Natives.
To assess the epidemiologic characteristics of the population susceptible to hepatitis A virus (HAV) infection and determine the natural history of infection, a retrospective survey was done using banked serum specimens. A random sample of 4030 Alaska Natives statewide was selected, stratified by year of birth and community of residence. Overall, 1988 serum samples (49.3%) tested positive for antibody to HAV (anti-HAV). Past HAV infection was strongly age-related, increasing from 7% in persons born since 1975 to 85% among persons born before 1945. Prevalence of infection also varied between regions. In small communities, a clear demarcation typically existed between previously infected older persons and younger anti-HAV-negative persons. This indicated that village-wide outbreaks of HAV infection have been the norm and appear to be dependent on the presence of a young susceptible population. Widespread vaccination with hepatitis A vaccine to maintain a high proportion of young anti-HAV-positive persons may be successful in preventing future epidemics.
Bulkow
L R
LR
Arctic Investigations Program, Centers for Disease Control and Prevention (CDC), Anchorage, AK 99501.
Wainwright
R B
RB
McMahon
B J
BJ
Middaugh
J P
JP
Jenkerson
S A
SA
Margolis
H S
HS
D000413:Alaska / Q000453:epidemiology; D003710:Demography; D006506:Hepatitis A / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D007198:Indians, North American; D004930:Inuit; D015995:Prevalence