HIV CARE CONTINUUMFROM HIV PREVENTION TO VIRAL SUPPRESSION

Today’s HIV treatments have been shown to be effective at suppressing the virus if taken as prescribed by a healthcare provider. Viral suppression, which means the amount of virus in the blood is less than 200 copies/mL or is so low it cannot be measured by a test, is the ultimate goal of HIV care and treatment.¹ While there is no cure for HIV, maintaining viral suppression can help people with HIV live longer, healthier lives and can help reduce the chance of passing HIV to others through sex.^1-3

The HIV care continuum is a public health model that maps the steps that individuals should go through from HIV diagnosis to viral suppression. This can help healthcare providers make sure people living with HIV are getting the care they need.⁴ In addition, the Centers for Disease Control and Prevention (CDC) tracks each step in the HIV care continuum to provide us with a population-level view of the progress the United States is making in addressing the HIV epidemic.⁵

Steps in the HIV Care Continuum

The HIV care continuum begins with a new HIV diagnosis and sets forth the steps people should take to get care and treatment with the objective of helping everyone achieve viral suppression. These steps include and are defined by the CDC as follows:

• Diagnosed. Receiving a positive HIV test confirmed by a healthcare provider. On a population level, statistics about new HIV diagnoses measure the percentage of the total number of people living with HIV who are aware of their status¹
• Linked to care. Having at least one documented CD4 or viral load test within 30 days of new HIV diagnosis. The goal is to get everyone who tests positive for HIV linked to care within one month of their diagnosis¹
• Received care. Having had at least one CD4 or viral load test run by a healthcare professional.¹ It tracks the percentage of people who have been diagnosed and received care in a given year. Once people get into care with a healthcare provider, they can start treatment⁴
• Retained in care. Having had two or more CD4 or viral load tests, performed at least three months apart.¹ It is important for people living with HIV to have ongoing care because they need to be on treatment regimens for their entire lives, and need the help of a healthcare provider to prescribe the medication, monitor the dosage, manage side effects, and help them protect their health^3,6
• Viral suppression. Having a viral load test result of less than 200 copies/mL at the most recent test. Essentially this means that the amount of virus in a person’s blood is so low it cannot be measured by a test. Viral suppression is the ultimate goal of HIV care and treatment. Moreover, people who maintain viral suppression have effectively no risk of passing HIV to others through sex¹

It should be noted that viral suppression is not a one-time HIV treatment goal. In order to achieve and maintain viral suppression and experience the health and prevention benefits it provides, people living with HIV must stay in constant care and continue treatment.⁷

Two Ways to Track
Data

Tracking data along the HIV care continuum is an important tool in efforts to help end the HIV epidemic because it allows public health agencies—on the national, state, and local levels—to identify gaps in care and determine the types of interventions that might help increase the number of people who achieve and maintain viral suppression.⁴

The CDC calculates the data in two ways. Diagnosis-based data are limited to people who have been diagnosed with HIV. These kinds of data are useful for tracking HIV treatment and care goals, analyzing disparities between groups of people living with HIV, and looking at different local responses to HIV. Linkage to care can only be calculated among people who have been diagnosed with HIV.¹

Prevalence-based data consider all people who are living with HIV, including those who have been diagnosed with HIV and the estimated number of people who have HIV but may not know it.¹ (In 2021, it was estimated that 1 in 8 people living with HIV in the US did not know it.⁸) These HIV-based data are useful for evaluating testing efforts, understanding the role new diagnoses play in the ultimate goal of achieving widespread viral suppression, and comparing data from the US with those of other countries.¹

Advocates use prevalence-based data in order to understand the full scope of the HIV epidemic, but progress along the HIV care continuum can be represented by both sets of data. While the number of people receiving HIV care or achieving viral suppression does not change between the two data sets, the percentage does, because the denominator changes. This is because prevalence-based data will always include more people; therefore, percentages will be lower.¹

HIV CARE CONTINUUM
PREVALENCE-BASED DATA
IN THE US, 2021

HIV CARE CONTINUUM
DIAGNOSIS-BASED DATA
IN THE US, 2021

Source: CDC. Monitoring selected national HIV prevention and care objectives by using HIV surveillance data—United States and 6 dependent areas, 2021. HIV Surveillance Supplemental Report. 2023;28(4).

HIV Prevention Continuum

The traditional HIV care continuum starts with a new HIV diagnosis and explains the steps that individuals should take from there to achieve viral suppression. While these are important markers for people living with HIV, many experts believe that, on both an individual and population level, there needs to be a separate HIV care continuum that addresses HIV prevention.⁹

Preventing new HIV infections is the cornerstone of the national plans to help end the HIV epidemic.^10,11 Traditional HIV prevention programs include behavioral interventions, such as efforts designed to increase condom use or stop needle sharing, and structural interventions that aim to remove barriers to these positive behaviors by changing policies, such as making condoms available, offering syringe services programs (SSPs), or providing HIV education.^9,12-15 These programs remain important, but the understanding of Treatment as Prevention (TasP), which is considered biomedical intervention, has radically changed the HIV prevention landscape.^16,17

Pre-exposure prophylaxis (PrEP)—another biomedical intervention—is a prevention strategy for people who are at risk for HIV. It involves using a prescription medicine to reduce the risk of new HIV infection.¹⁶ Research shows that PrEP medicine is effective if used correctly. The CDC recommends PrEP medicine for anyone who is at high risk of getting HIV.¹⁸

Moreover, we now understand that individuals who use HIV treatment as prescribed and achieve and maintain an undetectable viral load, meaning the amount of virus in the blood is so low it cannot be measured by a test, effectively cannot transmit the virus to another person through sex. This is sometimes referred to as U=U (or Undetectable=Untransmittable)—a memorable campaign that has become an important part of HIV prevention efforts.¹⁹

Since the existing HIV care continuum does not account for people at risk for HIV who might benefit from PrEP medicine, experts have proposed a separate HIV prevention continuum. The two continuums share the goal of preventing new HIV infections.⁹

HIV Status Neutral Prevention and Treatment Cycle

There is also a growing movement among those working in HIV for a new kind of continuum that can be applied to everyone regardless of their HIV status. The New York City Department of Health and Mental Hygiene (NYC DOHMH) has been a leader in proposing this type of paradigm, which it refers to as the HIV Status Neutral Prevention and Treatment Cycle. This model suggests a sequence that starts with HIV testing. If an individual is diagnosed with HIV, they move into the classic HIV care continuum and start treatment as soon as possible with the goal of achieving viral suppression.^20,21

If the individual tests negative, they move into an HIV prevention continuum, which consists of understanding their risk of HIV exposure, learning about PrEP medicine, and discussing with a healthcare provider whether it is an appropriate medication for them. Following those discussions, some people will start using PrEP medicine, while others may be guided toward other prevention methods, such as condom use and more frequent HIV testing.^20-22

The goal of an HIV status-neutral cycle, however, is to be able to apply the model to the population more broadly so that everyone can take next steps to protect themselves and their partners. This model recognizes that, to reach the ultimate goal of ending HIV transmission, everyone needs to remain engaged in prevention and care efforts. The hope is that an HIV status-neutral cycle can also help reduce stigma around HIV and HIV testing because it presents testing as something everyone should be doing to protect their health—not limited to those deemed “at risk” of getting HIV.²¹

Last, another important characteristic of the HIV status-neutral cycle is that it is viewed as continuous without a set beginning or end. This nonlinear representation more closely aligns with the experiences of people who are living with HIV as well as those who are at risk of getting it. Both groups benefit from an ongoing relationship with a healthcare provider whether they need HIV care and treatment or PrEP medicine and regular HIV testing. It also recognizes that there is no real endpoint to HIV care or prevention as both are continuous throughout people’s lives.^21,23

Source: Model adapted from Myers JE, et al. Open Forum Infect Dis. 2018;5(6). 
https://doi.org/10.1093/ofid/ofy097

*Viral suppression is defined as having less than 200 copies of HIV per milliliter of blood.⁷