Impact of hepatitis A vaccination of Indigenous children on notifications of hepatitis A in north Queensland.
OBJECTIVE
To describe the impact of a hepatitis A vaccination program for Indigenous children in north Queensland.


METHODS
Enhanced surveillance of all notified cases of hepatitis A in north Queensland from 1996 to 2003.


METHODS
North Queensland; population, 596 500 people, including about 6900 Indigenous children aged under five years.


METHODS
Hepatitis A vaccine was provided to Indigenous children in north Queensland from February 1999; two doses were recommended (at 18 months and 2 years of age), as was catch-up vaccination up to the sixth birthday.


RESULTS
In the 4 years 1996-1999, 787 cases of hepatitis A were notified in north Queensland, 237 (30%) of which were in Indigenous people. The average annual notification rates in Indigenous and non-Indigenous people during this period were 110 and 25 cases per 100 000 persons, respectively. In the first 4 years after introduction of the vaccination program (2000-2003), 66 cases of hepatitis A were notified. Only nine of the 66 (14%) were in Indigenous people. The average annual notification rates in Indigenous and non-Indigenous people in 2000-2003 were 4 and 2.5 cases per 100 000 persons, respectively.


CONCLUSIONS
Hepatitis A seems to have been eradicated from Indigenous communities in north Queensland very soon after the vaccination program began. The rapid decline in notifications in non-Indigenous as well as Indigenous people suggests the program quickly interrupted chains of transmission from Indigenous children to the broader community. To our knowledge this is the first evidence that a hepatitis A vaccination program targeting a high-risk population within a community can reduce disease in the broader community. Hepatitis A vaccine should be provided to other high-risk Indigenous children elsewhere in Australia.
Hanna
Jeffrey N
JN
Tropical Public Health Unit Network, Queensland Health, PO Box 1103, Cairns, QLD 4870, Australia. Jeffrey_hanna@health.qld.gov.au
Hills
Susan L
SL
Humphreys
Jan L
JL
D002626:Chemistry, Pharmaceutical; D002669:Child Welfare / Q000706:statistics & numerical data*; D002675:Child, Preschool; D018563:Disease Notification / Q000706:statistics & numerical data*; D006506:Hepatitis A / Q000208:ethnology* / Q000517:prevention & control* / Q000635:transmission; D022362:Hepatitis A Vaccines / Q000737:chemistry / Q000592:standards*; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary; D015994:Incidence; D011159:Population Surveillance; D017410:Practice Guidelines as Topic; D015397:Program Evaluation; D011793:Queensland / Q000453:epidemiology; D012307:Risk Factors; D014611:Vaccination / Q000592:standards* / Q000706:statistics & numerical data; D000095283:Australian Aboriginal and Torres Strait Islander Peoples
D022362:Hepatitis A Vaccines