Data Methods

Learn more about the data that informs AHEAD.

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HIV viral suppression indicator icon HIV viral suppression

HIV viral suppression was defined as a viral load result of <200 copies/mL at the most recent viral load test during the year of interest. The cutoff value of <200 copies/mL was based on the following definition of viral failure: viral load of ≥ 200 copies/mL. If multiple viral load tests were performed during the same month and could therefore qualify as “most recent,” the highest viral load (most severe) was selected. If the numerical result was missing or the result was a logarithmic value, the interpretation of the result (e.g., below limit) was used to determine viral suppression. Viral failure may indicate lack of adherence to ART. Of note, this indicator is only available for states that have complete data, which is defined as states that have reported at least 95% of laboratory results to their surveillance programs and have transmitted their data to CDC’s National HIV Surveillance System (NHSS). NHSS includes data for persons aged ≥ 13 years. 

Formula for the Viral Suppression indicator


HIV viral suppression for a given year was measured for persons aged ≥13 years and living with HIV infection that had been diagnosed by the beginning of the previous year and were alive at the end of the given year. As an example, viral suppression for 2017 was measured if all below conditions were met:

  • HIV infection was diagnosed by the end of the 2016 calendar year,
  • For the calendar year 2017, persons’ last known place of residence falls in any of the 42 jurisdictions with complete reporting,
  • Persons were alive at the end of the 2017 calendar year.

For the baseline year 2017, HIV viral suppression was available for the following 41 states and the District of Columbia: Alabama, Alaska, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Hampshire, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Washington, West Virginia, Wisconsin, and Wyoming.

Similarly, 2018 HIV viral suppression data was available for 41 states and the District of Columbia. However, the composition of the states changed. In 2018, viral suppression data was available for Nevada but not available for Connecticut. For the year 2019, the number of jurisdictions with HIV viral suppression data increased to include 44 states and the District of Columbia. Completeness of reporting varied among states and local jurisdictions. Data should be interpreted with caution for EHE areas (including Phase 1 EHE states, EHE jurisdictions, or states that contain EHE jurisdictions) that do not have laws requiring complete reporting of laboratory data or have incomplete reporting.

  • EHE areas without laws requiring complete reporting:
    • Idaho
    • New Jersey
  • EHE areas with incomplete reporting:
    • Arizona (Missing for 2017 & 2018)
    • Arkansas (Missing for 2017 & 2018)
    • Connecticut (Missing for 2018)
    • Idaho (Missing for 2017, 2018 & 2019)
    • Kansas (Missing for 2017, 2018 & 2019)
    • Kentucky (Missing for 2017, 2018 & 2019)
    • Nevada (Missing 2017)
    • New jersey (Missing for 2017, 2018 & 2019)
    • Pennsylvania (Missing for 2017, 2018 & 2019 though, jurisdictional data for Philadelphia is available)
    • Vermont (Missing for 2017, 2018 & 2019)
    • Puerto Rico (Missing for 2017, 2018 & 2019)

For more information on the surveillance measure of HIV viral suppression, please refer to the HIV Surveillance Report Supplemental Report Volume 26, Number 2.

Data should also be interpreted with caution for EHE areas (including Phase 1 EHE states, EHE jurisdictions, or states that contain EHE jurisdictions) with incomplete ascertainment of deaths. Areas with incomplete ascertainment of deaths in 2019 were Kansas, Massachusetts, Mississippi, Nevada, North Dakota, and Vermont.