Skip directly to search Skip directly to A to Z list Skip directly to site content
CDC Home

1993 Revised Classification System for HIV Infection and Expanded Surveillance Case Definition for AIDS Among Adolescents and Adults

On December 18, 1992, CDC published a revised classification system for human immunodeficiency virus (HIV) infection and an expanded surveillance case definition for acquired immunodeficiency syndrome (AIDS) among adolescents and adults in the United States (1). * Based on the clinical standard for immunologic monitoring of persons infected with HIV, the revised HIV classification system includes the CD4+ T-lymphocyte measurement in the categorization of HIV-related clinical conditions and replaces the HIV classification system published in 1986 (2). In addition, the expanded AIDS surveillance case definition includes all HIV-infected persons who have less than 200 CD4+ T-lymphocytes/uL or a CD4+ T-lymphocyte percent of total lymphocytes less than 14, or who have been diagnosed with pulmonary tuberculosis, invasive cervical cancer, or recurrent pneumonia. The new AIDS surveillance case definition retains the reporting criteria listed in the 1987 AIDS surveillance case definition (3). The objectives of the expansion are to reflect more accurately the number of persons with severe HIV-related morbidity and immunosuppression and to simplify the reporting process. Beginning January 1, 1993, this expanded AIDS surveillance case definition is to be used by all states and territories for AIDS case reporting.

  • Single copies of the document will be available in mid-January from the CDC National AIDS Clearinghouse, P.O. Box 6003, Rockville, MD 20849-6003; telephone (800) 458-5231.


  1. CDC. 1993 Revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR 1992;41(no. RR-17).

  2. CDC. Classification system for human T-lymphotropic virus type III/lymphadenopathy-associated virus infections. MMWR 1986;35:334-

  3. CDC. Revision of the CDC surveillance case definition for acquired immunodeficiency syndrome. MMWR 1987;36(no. S-1).

Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of Health and Human Services.

References to non-CDC sites on the Internet are provided as a service to MMWR readers and do not constitute or imply endorsement of these organizations or their programs by CDC or the U.S. Department of Health and Human Services. CDC is not responsible for the content of pages found at these sites. URL addresses listed in MMWR were current as of the date of publication.

All MMWR HTML versions of articles are electronic conversions from typeset documents. This conversion might result in character translation or format errors in the HTML version. Users are referred to the electronic PDF version ( and/or the original MMWR paper copy for printable versions of official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

**Questions or messages regarding errors in formatting should be addressed to The U.S. Government's Official Web PortalDepartment of Health and Human Services
Centers for Disease Control and Prevention   1600 Clifton Road Atlanta, GA 30329-4027, USA
800-CDC-INFO (800-232-4636) TTY: (888) 232-6348 - Contact CDC–INFO
A-Z Index
  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #