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Hepatitis, Viral, Acute
1996 Case Definition
Clinical case definition
An acute illness with a) discrete onset of symptoms and
b) jaundice or elevated serum aminotransferase levels
Laboratory criteria for diagnosis:
- Hepatitis A: immunoglobulin
M (IgM) antibody to hepatitis A virus (anti-HAV) positive
- Hepatitis B:
- IgM antibody to hepatitis B core antigen (anti-HBc)
positive or hepatitis B surface antigen (HBsAg) positive
- IgM anti-HAV negative (if done)
- Hepatitis C:
- Serum aminotransferase levels greater than
2.5 times the upper limit of normal, and
- IgM anti-HAV negative, and
- IgM anti-HBc negative (if done) or HBsAg negative,
and
- Antibody to hepatitis C virus (anti-HCV) positive,
verified by a supplemental test
- Non-A, Non-B hepatitis:
- Serum aminotransferase levels greater than
2.5 times the upper limit of normal, and
- IgM anti-HAV negative, and
- IgM anti-HBc negative (if done) or HBsAg negative,
and
- Anti-HCV negative (if done)
- Delta hepatitis*: HBsAg or IgM anti-HBc
positive and antibody to hepatitis delta virus positive
Case classification
Confirmed: a case that
meets the clinical case definition and is laboratory confirmed or, for
hepatitis A, a case that meets the clinical case definition and occurs
in a person who has an epidemiologic link with a person who has laboratory-confirmed
hepatitis A (i.e., household or sexual contact with an infected person
during the 15-50 days before the onset of symptoms)
Comment
- Persons who have chronic hepatitis or persons identified
as HBsAg positive or anti-HCV positive should not be reported as
having acute viral hepatitis unless they have evidence of an acute
illness compatible with viral hepatitis (with the exception of
perinatal hepatitis B infection). (See Hepatitis, Viral, Perinatal
Hepatitis B Virus Infection Acquired in the United States or U.S.
Territories.)
- Up to 20% of acute hepatitis C cases will be anti-HCV
negative when reported and will be classified as non-A, non-B hepatitis
because some (5%-10%) have not yet seroconverted and others (5%-10%)
remain negative even with prolonged follow-up (6).
- Available serologic tests for anti-HCV do not distinguish
between acute and chronic or past infection. Thus, other causes
of acute hepatitis should be excluded for anti-HCV positive patients
who have an acute illness compatible with viral hepatitis.
* Delta Hepatitis is not a nationally
notifiable disease.
References
6. Kuo G,
Choo Q-L, Alter HJ, et al. An assay for circulating antibodies to a major
etiologic virus of human non-A, non-B hepatitis. Science 1989;244:362-4.
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