Reuters Health Information (2005-07-12): Hepatitis A rates at new low since vaccine program begun in US
Hepatitis A rates at new low since vaccine program begun in US
Last Updated: 2005-07-12 16:00:22 -0400 (Reuters Health)
NEW YORK (Reuters Health) - Hepatitis A incidence has
fallen to a historic low since routine hepatitis A vaccination of
children was implemented in the US in 1999, according to a report in
the Journal of the American Medical Association for July 13.
Since 1996, hepatitis A vaccination has been advised for at-risk
individuals, such as men who have sex with men and illicit drug users.
In 1999, this recommendation was extended to children living in 11
states with the highest incidence of disease. In 6 additional states
with above average rates, it was advised that hepatitis A vaccination
be considered for children.
In the present study, Dr. Annemarie Wasley, from the Centers for
Disease Control and Prevention in Atlanta, and colleagues evaluated
hepatitis A cases that were reported to the National Notifiable Disease
Surveillance System since 1990.
Between the early/mid 1990s and 2003, overall hepatitis A rates fell
76% to reach an all time low -- 2.6 cases per 100,000. The previous
nadir, 9.1 cases per 100,000, occurred in 1992.
The drop in hepatitis A rates in vaccinating states was 88%, whereas
the reduction elsewhere was 53%, the investigators point out. Rates
among children fell by 87%, while those among older subjects fell by
In the early/mid 1990s, cases from vaccinating states accounted for
65% of the total disease burden, the authors note. By 2003, however,
cases from such states represented only 33% of the national total.
The proportion of hepatitis A cases involving children fell from 35%
to 19%, the report indicates. Since 2001, adults have had higher
hepatitis A rates than children. Currently, the highest rates are among
men between 25 and 39 years of age.
In a related editorial, Dr. Pierre Van Damme and Dr. Koen Van Herck,
from the University of Antwerp in Belgium, comment that factors other
than vaccination, such as improved environmental and hygienic
conditions, could have contributed to the drop in hepatitis A rates.
"Only continued disease surveillance will allow confirmation of the
real impact" of the vaccine program.