Clinical Case Definition of HIV

1. In adults, adolescents, or children aged greater than or equal to 18 months**, a reportable case of HIV infection must meet at least one of the following criteria:

    

   Laboratory Criteria

    

   Positive result on a screening test for HIV antibody (e.g., repeatedly reactive enzyme immunoassay (EIA)), followed by a positive result on a confirmatory (sensitive and more specific) test for HIV antibody (e.g., Western blot or immunofluorescence antibody test).

    

   OR

    

   Positive result or report of a detectable quantity on any of the following HIV virologic (nonantibody) tests:

    

   • HIV nucleic acid (DNA or RNA) detection (e.g., DNA polymerase chain reaction [PCR] or plasma HIV-1 RNA)***

    

   • HIV p24 antigen test, including neutralization assay

    

   • HIV isolation (viral culture)

    

   OR

    

   Clinical or Other Criteria (if the above laboratory criteria are not met)

    

   Diagnosis of HIV infection, based on the laboratory criteria above, that is documented in a medical record by a physician

    

   OR

    

   Conditions that meet criteria included in the case definition for AIDS (17-19)
   
   

 

2. In a child aged less than 18 months, a reportable case of HIV infection must meet at least one of the following criteria:

    

   Laboratory Criteria

    

   Definitive

    

   Positive results on two separate specimens (excluding cord blood) using one or more of the following HIV virologic (nonantibody) tests:

    

   • HIV nucleic acid (DNA or RNA) detection

   • HIV p24 antigen test, including neutralization assay, in a child greater than or equal to 1 month of age

   • HIV isolation (viral culture)

    

   OR

    

   Presumptive

    

   A child who does not meet the criteria for definitive HIV infection but who has:

    

   • Positive results on only one specimen (excluding cord blood) using the above HIV virologic tests and no subsequent negative HIV virologic or negative HIV antibody tests

    

   OR

    

   Clinical or Other Criteria (if the above definitive or presumptive laboratory criteria are not met)

    

   Diagnosis of HIV infection, based on the laboratory criteria above, that is documented in a medical record by a physician

    

   OR

    

   Conditions that meet criteria included in the 1987 pediatric surveillance case definition for AIDS (17,19)
   
   

 

3. A child aged less than 18 months born to an HIV-infected mother will be categorized for surveillance purposes as "not infected with HIV" if the child does not meet the criteria for HIV infection but meets the following criteria:

    

   Laboratory Criteria
   Definitive
   At least two negative HIV antibody tests from separate specimens obtained at greater than or equal to 6 months of age

    

   OR

    

   At least two negative HIV virologic tests* from separate specimens, both of which were performed at greater than or equal to 1 month of age and one of which was performed at greater than or equal to 4 months of age

    

   AND

    

   No other laboratory or clinical evidence of HIV infection (i.e., has not had any positive virologic tests, if performed, and has not had an AIDS-defining condition)

    

   OR

    

   Presumptive

    

   A child who does not meet the above criteria for definitive "not infected" status but who has:

    

   • One negative EIA HIV antibody test performed at greater than or equal to 6 months of age and NO positive HIV virologic tests, if performed

      

     OR

      

   • One negative HIV virologic test* performed at greater than or equal to 4 months of age and NO positive HIV virologic tests, if performed

      

     OR

      

    

   • One positive HIV virologic test with at least two subsequent negative virologic tests****, at least one of which is at greater than or equal to 4 months of age; or negative HIV antibody test results, at least one of which is at greater than or equal to 6 months of age
     
     

    

   AND

    

   No other laboratory or clinical evidence of HIV infection (i.e., has not had any positive virologic tests, if performed, and has not had an AIDS-defining condition).

    

   OR

    

   Clinical or Other Criteria (if the above definitive or presumptive laboratory criteria are not met)

    

   Determined by a physician to be "not infected", and a physician has noted the results of the preceding HIV diagnostic tests in the medical record

    

   AND

    

   NO other laboratory or clinical evidence of HIV infection (i.e., has not had any positive virologic tests, if performed, and has not had an AIDS-defining condition)

    

4. A child aged less than 18 months born to an HIV-infected mother will be categorized as having perinatal exposure to HIV infection if the child does not meet the criteria for HIV infection (II) or the criteria for "not infected with HIV" (III).

* Draft revised surveillance criteria for HIV infection were approved and recommended by the membership of the Council of State and Territorial Epidemiologists (CSTE) at the 1998 annual meeting (11).

** Children aged greater than or equal to 18 months but less than 13 years are categorized as "not infected with HIV" if they meet the criteria in III.

*** In adults, adolescents, and children infected by other than perinatal exposure, plasma viral RNA nucleic acid tests should NOT be used in lieu of licensed HIV screening tests (e.g., repeatedly reactive enzyme immunoassay). In addition, a negative (i.e., undetectable) plasma HIV-1 RNA test result does not rule out the diagnosis of HIV infection.

**** HIV nucleic acid (DNA or RNA) detection tests are the virologic methods of choice to exclude infection in children aged less than 18 months. Although HIV culture can be used for this purpose, it is more complex and expensive to perform and is less well standardized than nucleic acid detection tests. The use of p24 antigen testing to exclude infection in children aged less than 18 months is not recommended because of its lack of sensitivity.

***** It is recommended that should a laboratory result shows a positive result for an EIA and a negative, or non-reactive, result for a Western Blot or IFA, the client be re-tested.