Data Methods

The HIV surveillance presented on this site are from the National HIV Surveillance System (NHSS), managed by the Centers for Disease Control and Prevention (CDC). NHSS is the primary source for monitoring HIV trends in the United States. The CDC funds and assists state and local health departments to collect the information. States and local jurisdictions, including the District of Columbia and Puerto Rico, have laws or regulations that require confidential reporting by name.

Overview

There are 6 core EHE indicators reported on this site. Five of the 6 core EHE indicators are from the National HIV Surveillance System (NHSS), managed by the Centers for Disease Control and Prevention (CDC). NHSS is the primary source for monitoring HIV trends in the United States. The CDC funds and assists state and local health departments to collect the data. States and local jurisdictions, including the District of Columbia and Puerto Rico, have laws or regulations that require confidential reporting by name for persons with a confirmed HIV diagnosis. After the removal of personally identifiable information, data from these reports are submitted to CDC. Health departments report these de-identified data to CDC so that information from around the country can be analyzed to determine who is being affected, which can inform where HIV prevention and treatment resources are most needed. The PrEP coverage indicator uses 4 different data sources. Please see PrEP coverage section for more details.

Data on HIV diagnoses should be interpreted with caution. Data may not be representative of all persons living with HIV because not all persons with HIV have been tested. Also, many states offer anonymous testing; the results of anonymous tests are not reported to the confidential name-based HIV registries of state and local health departments. The data presented on this site provide the minimum number of persons for whom HIV infection has been diagnosed and reported to NHSS. In addition, because surveillance practices differ, the reporting and updating of a person’s clinical and vital status differ among states. Data reported to the NHSS are considered preliminary until a 12-month reporting delay has been reached.

The NHSS data displayed on this site may not be comparable to surveillance data published by individual jurisdictions. This is because: (1) CDC de-duplicates cases at the national level, and (2) national data have been statistically adjusted to account for missing transmission category. For more information, please refer to the CDC fact sheet at the following link: Terms, Definitions, and Calculations | Surveillance Overview | Statistics Center | HIV/AIDS | CDC.

The baseline year for data used for calculating the Ending the HIV Epidemic (EHE) indicators (incidence, diagnoses, knowledge of status, linkage to care, viral suppression, and PrEP) is 2017.

Data for year 2022 and 2023 are considered preliminary and based on data reported to CDC’s National HIV Surveillance System as of September 2023. Diagnoses data are preliminary through September 2023. Linkage to HIV Medical Care and PrEP Coverage are preliminary through June 2023.