HIV blood screening solutions to support early diagnosis and care continuity

Primary care providers are critical frontline leaders for patients who would benefit from HIV screening, diagnosis, and entry into ongoing treatment. 

The CDC recommends routine HIV blood screening for all individuals ages 13 to 64 at least once as part of routine healthcare (more frequently for those with increased risk factors).¹ PCPs are often the first point of contact in identifying undiagnosed HIV infection and accelerating referrals to appropriate infectious disease specialty care. 

And it is precisely that early diagnosis with subsequent prompt treatment and retention in HIV care pathways that helps patients live long, healthy lives while also reducing the risk of onward transmission.

In this article:

Clinical challenge | Why it matters | Ordering recommendations | Interpreting test results | Next steps | Supporting resources

Clinical challenge: Opportunities for HIV testing in primary care settings

Normalizing HIV screening tests

For many PCPs, the challenge is not whether HIV testing is important, but how to make it routine and actionable within a busy practice. Patients who do not perceive themselves to be at risk may go untested unless screening is normalized. 

Ongoing testing needs

Screening is only the first step. A second challenge for both primary care and specialty clinicians is ensuring that ongoing testing continues after diagnosis. Patients living with HIV require longitudinal laboratory assessment to guide antiretroviral therapy (ART) selection, monitor virologic response, evaluate immune status, and identify comorbidities that affect treatment and long-term outcomes. 

Understanding the value of a comprehensive testing strategy helps providers position HIV screening tests as part of a broader care pathway rather than a one-time event.

Why it matters: Clinical and public health importance of early HIV blood testing

Status awareness

Routine HIV blood screening remains necessary because a meaningful proportion of people living with HIV are still unaware of their status. Nearly 13% of people with HIV in the US don’t realize they have the infection.² To compound the seriousness of the situation, as many as 40% of new infections are transmitted by people who are unaware of their HIV status.¹

Early diagnosis

Earlier diagnosis changes the trajectory of care—and the course of a patient’s life. The CDC’s recommended laboratory algorithm uses a fourth-generation HIV-1/2 antigen-antibody combination assay that can detect infection earlier than traditional testing approaches. In fact, it can simultaneously detect HIV-1/2 antibodies and HIV-1 p24 antigen, which enables detection in the acute phase of infection.³

Earlier detection gives clinicians the opportunity to confirm HIV infection promptly, begin the workup for treatment—including rapid initiation of ART—and connect patients to HIV care and ongoing testing to assess immune compromise progression.

Awareness initiatives

National HIV Testing Day, observed annually on June 27, encourages people to get tested, know their status, and get linked to care and treatment. For PCPs, the observance is a reminder to normalize screening conversations and reinforce that knowing one’s status is foundational to ending the HIV epidemic in the United States.

Ordering recommendations: Evidence-based guidance for fourth-generation HIV blood screening algorithm

The HIV-1/2 Antigen and Antibodies, Fourth Generation, with Reflexes combination immunoassay offered by Quest Diagnostics adheres to the CDC-recommended fourth-generation HIV screening algorithm. This test protocol helps diagnose HIV-1 and HIV-2 infection (including acute infection) and differentiate HIV-1 from HIV-2.

Additionally, Quest offers the HIV-1 and HIV-2 RNA, Qualitative Real-Time PCR test typically used to detect HIV-1 RNA in human serum and plasma by PCR as an aid in diagnosis of HIV-1 infection.

Beyond those screening and confirmation tests, other options are available from Quest to enable HIV viral load testing to monitor the condition over time.

Recommended tests for HIV blood screening and confirmation

HIV-1/2 Antigen and Antibodies, Fourth Generation, with Reflexes

• Test code: 91431
• CPT^® code: 87389

HIV-1 and HIV-2 RNA, Qualitative Real-Time PCR

• Test code: 14312
• CPT codes: 87535*, 87538*

Related tests

^* CPT code is subject to a Medicare Limited Coverage Policy and may require a signed ABN when ordering.

The CPT^® codes provided are based on American Medical Association guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

Reflex tests are performed at an additional charge.

Interpreting test results: Understanding the HIV blood screening algorithm with confidence

The fourth-generation HIV screening test results can either be nonreactive or reactive.

A nonreactive HIV test result indicates there is no evidence of HIV infection, although patients with recent HIV exposure may require repeat testing based on timing and clinical suspicion.

If the HIV-1/2 Ag/Ab combination immunoassay shows a reactive result, the clinician should then look to the HIV-1/HIV-2 antibody differentiation immunoassay to fully interpret the results. There are 4 primary HIV test result categories:

• HIV-1 Ab-positive, HIV-2 Ab-negative: Demonstrates the results are positive for HIV-1 antibodies and an established HIV-1 infection is present.
• HIV-1 Ab-negative, HIV-2 Ab-positive: Shows the results are positive for HIV-2 antibodies and HIV-2 infection is present.
• HIV-1 reactive and HIV-2 nonreactive: Demonstrates that HIV infection is present, but it is not able to be classified at this stage.
• HIV-1/2 Ab negative or indeterminate: Indicates HIV antibodies were not confirmed, HIV-1 RNA was not detected, and there is no laboratory evidence of HIV-1 infection. However, follow-up qualitative PCR testing for HIV-2 should be performed.

Simplified reporting of HIV test results

Quest’s streamlined test results format makes it easy to identify a patient’s HIV status by listing the final interpretation at the top of the report.

Next steps: From reactive HIV test result to ongoing management

A positive HIV diagnosis should trigger immediate, coordinated follow-up.

Primary care providers can initiate the connection to infectious disease clinicians for specialty HIV care. And Quest has comprehensive test offerings for ongoing HIV management, which can help

• Guide selection of antiretroviral therapy drugs
• Evaluate HIV prognosis, assess effectiveness of ART, and decide on a treatment regimen
• Monitor overall patient health, including guideline-recommended testing for comorbidities

Supporting resources