POPS Appendix F – CDC Surveillance Case Definitions
HIV Infection [1]
This revised definition of HIV infection, which applies to any HIV (e.g., HIV-1 or HIV-2), is intended for public health surveillance only. It incorporates the reporting criteria for HIV infection and AIDS into a single case definition. The revised criteria for HIV infection update the definition of HIV infection implemented in 1993; the revised HIV criteria apply to AIDS-defining conditions for adults and children, which require laboratory evidence of HIV. This definition is not presented as a guide to clinical diagnosis or for other uses.
I. Infected adults, adolescents, or children greater than or equal to 18 months [2] of age
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), 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) [3
- HIV p24 antigen test, including neutralization assay
- HIV isolation (viral culture)
Clinical or Other Criteria (if the above laboratory criteria are not met)
Diagnoses 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
II. Infected children less than 18 months of age
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
Clinical or Other Criteria (if the above laboratory criteria are not met)
- Diagnoses 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
III. Not infected following perinatal exposure
A child less than 18 months of age 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 [1] 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 grater than or equal to 6 months of age and NO positive HIV virologic tests, if performed, or
- One negative HIV virologic test [1] 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 [4], 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 a 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).
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)
IV. Perinatal Exposure
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.
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Chlamydia trachomatis, Genital Infections
To ensure the quality of STD surveillance data and their comparability within and between state and local jurisdictions, all program areas will adopt CDC case definitions.
Clinical description, laboratory criteria for diagnosis, and case classification
Comment
For all surveillance case reports, laboratory confirmation of chlamydial infection is required. In some jurisdictions, syndromes such as MPC and NGU have been accepted as reports of chlamydial infection without any laboratory test; however, a high proportion of NGU is caused by other pathogens and for MPC, often no bacterial etiology can be found.
Gonorrhea
To ensure the quality of STD surveillance data and their comparability within and between state and local jurisdictions, all program areas will adopt CDC case definitions.
Clinical description, laboratory criteria for diagnosis, and case classification
Comment
A clinical diagnosis of gonorrhea without laboratory confirmation (e.g., based on the presence of urethral discharge alone) should not be reported as a gonorrhea case.
Syphilis
To ensure the quality of STD surveillance data and their comparability within and between state and local jurisdictions, all program areas will adopt CDC case definitions.
Syphilis is a complex sexually transmitted disease that has a highly variable clinical course. Classification by a clinician with expertise in syphilis may take precedence over the following case definitions developed for surveillance purposes.
Syphilis, primary
Clinical description, laboratory criteria for diagnosis, and case classification
Syphilis, secondary
Clinical description, laboratory criteria for diagnosis, and case classification
Syphilis, latent
Clinical description and case classification
Syphilis, latent unknown duration
Clinical description and case classification
Neurosyphilis
Clinical description, laboratory criteria for diagnosis, and case classification
Syphilis, late, with clinical manifestations other than neurosyphilis (late benign syphilis and cardiovascular syphilis)
Clinical description, laboratory criteria for diagnosis, and case classification
Syphilitic Stillbirth
Comment
For reporting purposes, syphilitic stillbirths should be reported as cases of congenital syphilis.
Syphilis, Congenital
Clinical description, laboratory criteria for diagnosis, and case classification
Comment
Congenital and acquired syphilis may be difficult to distinguish when a child is seropositive after infancy. Signs of congenital syphilis may not be obvious, and stigmata may not yet have developed. Abnormal values for CSF VDRL, cell count, and protein, as well as IgM antibodies, may be found in either congenital or acquired syphilis. Findings on radiographs of long bones may help because radiographic changes in the metaphysis and epiphysis are considered classic signs of congenitally acquired syphilis. The decision may ultimately be based on maternal history and clinical judgment. In a young child, the possibility of sexual abuse should be considered as a cause of acquired rather than congenital syphilis, depending on the clinical picture. For reporting purposes, congenital syphilis includes cases of congenitally acquired syphilis among infants and children as well as syphilitic stillbirths.
Notes:
1 - 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. Draft versions of these criteria were previously reviewed by state HIV/AIDS surveillance staffs, CDC, CSTE, and laboratory experts. In addition, the pediatric criteria were reviewed by an expert panel of consultants. (External Pediatric Consultants: C. Hanson, M. Kaiser, S. Paul, G. Scott, and P. Thomas. CDC staff: J. Bertolli, K. Dominguez, M. Kalish, M.L. Lindegren, M. Rogers, C. Schable, R.J. Simonds, and J. Ward)
2 - 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.
3 - 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.
4 - HIV nucleic acid (NDA 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.
5 - Inadequate treatment consists of any nonpenicillin therapy or penicillin administered <30 days before delivery.