—Christine. M. Kukka, Project Manager, HBV Advocate
The number of documented new hepatitis B virus
(HBV) infections dropped 64% between 2000 to 2011 due primarily to
immunization, according to new U.S. Centers for Disease Control and
Prevention (CDC) report.
However, this number
under-estimates the true incidence of hepatitis B because the infection
can be asymptomatic and is rarely reported to health agencies. CDC
estimates that the true number of new HBV infections in the United
States each year ranges from 7,400 to 86,200.
In 2011, the highest HBV
infection rates were in people aged 30–39. African-Americans bore the
brunt of new infections, with 1.4 cases per 100,000 people, compared to
Asian-Americans and Hispanics who had acute infection rates of 0.4
cases per 100,000. The national infection rate was 0.9 per 100,000.
While Asian-Americans have the
highest rates of chronic hepatitis B infection, most of those
infections occurred at birth or early childhood, these new infections
occurred primarily among adults.
Most of the new infections were
reported to CDC because of jaundice or severe liver damage that
resulted in hospitalization and a hepatitis B diagnosis.
Of the new infections, 62.4% of
patients reported they had no known risk factors or behaviors that may
have led to their infection. Of the 38% with reported risk factors:
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18.3% reported recent injecting drug use
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6.5% reported sexual contact with a person with confirmed or suspected hepatitis B
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19.1% indicated they had sex with another man
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33.3% reported sex with two or more partners (heterosexual)
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1.1% indicated household contact with someone with confirmed or suspected hepatitis B infection
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And a small percentage of
patients reported exposure to the virus through medical procedures or
working in health care settings.
The death rate from hepatitis B
has been increasing among persons aged 55–64, and most were
Asian-American and male. The death rate increased from 1.4 deaths per
100,000 in 2006 to 1.7 deaths in 2010.
Center for Disease Control and Prevention, Division of Viral Hepatitis
Surveillance for Viral Hepatitis – United States, 2011
As part of CDC’s National
Notifiable Disease Surveillance System (NNDSS), viral hepatitis
case-reports are received electronically from state health departments
via CDC’s National Electronic Telecommunications System for
Surveillance (NETSS). Although surveillance infrastructure is in place
for reporting of acute infection, reports of chronic hepatitis B and C,
which account for the greatest burden of disease, are not submitted by
all states. Surveillance capacity to monitor both acute and chronic
viral hepatitis is limited at the state and local levels, resulting in
underreporting and incomplete variable quality data that is insufficient
for understanding the magnitude of viral hepatitis. Data in this
report should be interpreted with the consideration that reported cases
of acute or chronic viral hepatitis represent only those relatively
few infected persons who were detected, diagnosed, met a stringent case
definition, and eventually reported to CDC in 2011.
Because most acute and chronic
infections are not reported, this Summary is mainly useful in detecting
major trends in viral hepatitis A (HAV), B (HBV) and C (HCV).
Labels: epidemiology, statistics