Data for the years 2021 & 2022 are preliminary. Due to the impact of the COVID-19 pandemic, data for the year 2020 should be interpreted with caution. Visit coronavirus.gov for the latest Coronavirus Disease (COVID-19) updates.
COVID-19 disruptions in HIV, diagnosis, care and reporting of deaths during 2020 have also made incidence, prevalence, and knowledge of status estimates derived from a CD4-based model, unreliable. Therefore, the HIV surveillance supplemental report Estimated HIV Incidence and Prevalence in the U.S., which provides data on estimated incidence, prevalence, and knowledge of status in the U.S., was not published by CDC this year.

PrEP | AHEAD

Glossary

Learn more about the terminology used in the Ending the HIV Epidemic: A Plan for America initiative.

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Click on a term to view its definition.

PrEP

Pre-exposure prophylaxis (or PrEP) is daily medicine that people at very high risk for HIV can take to prevent HIV. PrEP medications can stop HIV from taking hold and spreading throughout your body. When taken daily, PrEP medication is highly effective for preventing HIV from sex or injection drug use. PrEP is much less effective when it is not taken consistently.

Formula for the PrEP Coverage indicator