What Is the HIV Care Continuum?
The HIV care continuum is a public health model that outlines the steps or stages that people with HIV go through from diagnosis to achieving and maintaining viral suppression (a very low or undetectable amount of HIV in the body).
The steps are:
- diagnosis of HIV infection
- linkage to HIV medical care
- receipt of HIV medical care
- retention in medical care
- achievement and maintenance of viral suppression
Why Is the HIV Care Continuum Important?
The HIV care continuum is useful both as an individual-level tool to assess care outcomes, as well as a population-level framework to analyze the proportion of people with HIV in a given community who are engaged in each successive step. This helps policymakers and service providers better pinpoint where gaps in services might exist and develop strategies to better support people with HIV to achieve the treatment goal of viral suppression.
Supporting people with HIV to move through the steps of the continuum to achieve and maintain viral suppression is critical. There are important health benefits to getting the viral load as low as possible: people living with HIV who get and keep an undetectable viral load can live long, healthy lives. There is also a major prevention benefit: people with HIV who take HIV medicine daily as prescribed and get and keep an undetectable viral load have effectively no risk of transmitting HIV to their HIV-negative sexual partners.
For individuals with HIV to receive these benefits, they need to be aware that they have HIV, be connected to and engaged in regular HIV care, and receive and adhere to treatment with HIV medicine. However, there are obstacles that can contribute to poor engagement in HIV care and treatment, substantially limiting the effectiveness of efforts to improve health outcomes for those with HIV and reduce new HIV transmissions.
Knowing where the gaps are most pronounced, and for what populations, is vital to knowing how, where, and when to intervene to break the cycle of HIV transmission in the United States.
What Does the HIV Care Continuum Show?
This HIV Care Continuum chart is based on the prevalence of HIV in the U.S. Prevalence describes the number of people living with HIV at a given time, regardless of when they were infected or whether they have received a diagnosis. (Some people may have HIV but not know it). Prevalence data is useful for planning and resource allocation, as it reflects the number of people currently needing HIV care and treatment services. Prevalence rates are also useful for comparing HIV disease between populations and for monitoring trends over time. (Read more about the prevalence-based approach to monitoring the HIV care continuum and how it is used.)
According to CDC data published in May 2021 an estimated 1.2 million people aged 13 and older were living with HIV in the United States at the end of 2019. Of those 1.2 million people:
- Diagnosis—An estimated 87% were diagnosed. That means that 13% of people with HIV (nearly 1 in 7) did not know they had HIV and were therefore not accessing the care and treatment they need to stay healthy and prevent transmitting the virus to their partners.
- Receipt of Care—Approximately 66% had received HIV medical care. CDC measures receipt of care as the percentage of persons with diagnosed HIV who had at least one CD4 or viral load test run by a health care professional in a given year. Once in medical care, people can start HIV medicine (called antiretroviral therapy or ART) to help them stay healthy and protect their partners. Initiating ART is recommended for all people with diagnosed HIV.
- Retention in Care—Approximately 50% were retained in care. CDC measures retention in care as the percentage of persons with diagnosed HIV who had two or more CD4 or viral load tests, performed at least three months apart. People with HIV who have ongoing, regularly scheduled medical care have been shown to have better health outcomes and increased safer sexual behaviors.
- Viral Suppression—An estimated 57% had achieved viral suppression. CDC measures viral suppression as a viral load test result of <200 copies/mL at the most recent viral load test during measurement year.
- Linkage to care—According to CDC, of those who received an HIV diagnosis in 2019, 81% were linked to care within one month. This figure is calculated differently from other steps in the continuum, so it cannot be directly compared. CDC defines linkage as having one or more documented CD4 or viral load tests within 30 days (1 month) of HIV diagnosis. The denominator is limited to the number of people receiving an HIV diagnosis in a given year, rather than the total number of people living with HIV that is used in the calculations for the other continuum steps. Rapid linkage to care is important because it can shorten the time to viral suppression, which helps people stay healthy and virtually eliminates the chance of onward transmission.
Different analyses present the steps or stages of the HIV care continuum in different ways. For example, CDC also offers a diagnosis-based continuum, which shows each step as a percentage of the number of people with diagnosed HIV. For that continuum, among people ages 13 and older with diagnosed HIV at year-end 2019, 81% were linked to medical care within one month of diagnosis, 76% had received HIV medical care, 58% were retained in care, and 66% had achieved viral suppression. (Read about this diagnosis-based approach to monitoring the HIV care continuum.)
Further, a 2019 CDC analysis shows that the vast majority (about 80 percent) of new HIV infections in the U.S. in 2016 came from the nearly 40 percent of people who either did not know they had HIV or who had received a diagnosis but were not receiving HIV care and treatment. This highlights the need to increase the proportion of people with HIV who are aware of their status and to help those with HIV get into and remain engaged in care and treatment.
How Is the HIV Care Continuum Being Used?
Federal, state and local health departments, community-based organizations, health care providers, and people with HIV continue to use the HIV care continuum to measure progress toward HIV goals as well as to pinpoint where gaps in services may exist in connecting individuals with HIV to sustained, quality care and treatment. Knowing where drop-offs are most pronounced, and for what populations, helps policymakers, public health officials, and health care providers implement system improvements to support all persons with HIV so they are able to successfully navigate the continuum and achieve and maintain viral suppression.
Take a Closer Look
To learn more about the HIV care continuum in the U.S. and how the steps are defined and measured, see these resources: