Skip to content

HIV-1 Viral Load by Nucleic Acid Sequence-Based Amplification (NASBA) Probe Assay (Serum/Plasma)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of HIV-1 virus in your blood or plasma. It helps track how well your treatment is working and whether the virus is still active.

Quick summary

["This test is critical for managing HIV treatment and monitoring viral suppression."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
38998-1
Short code
HIV 1+HCV RNA SerPl BPU Ql NAA+probe
Synonyms
HIV 1+HCV RNA SerPl BPU Ql NAA+probe
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
CPT
86701
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

What This Test Measures

The test detects genetic material (RNA) from the HIV-1 virus using a highly sensitive method. It quantifies the viral load, which reflects the number of active virus particles in your blood or plasma. Lower levels often indicate effective treatment, while higher levels may signal treatment resistance or failure.

Why It’s Done

Your healthcare provider may order this test if you’re on HIV treatment to check if the virus is being controlled. It’s also used during initial diagnosis, when starting new treatments, or if you experience symptoms like fever, fatigue, or changes in immune function.

How the Test Works

The test uses a specialized probe to detect and amplify tiny amounts of HIV-1 RNA from a blood or plasma sample. This method is highly sensitive and can detect even very low levels of virus, helping doctors monitor treatment progress accurately.

What to Expect Before the Test

No special preparation is needed, but you may be asked to fast or avoid certain medications for a few hours before the blood draw. Bring your current medications to your appointment to confirm which ones to stop or adjust.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

A consistently low viral load (typically below 200 copies/mL) is strongly associated with undetectable viral replication and reduced risk of HIV transmission. Regular testing helps prevent drug resistance, ensures optimal treatment adherence, and supports long-term health. High or rising viral loads may require adjustments to your treatment plan.

Short name

HIV-1 Viral Load

Frequently asked questions

How often should I get this test?
Your healthcare provider will determine the timing based on your treatment history and overall health. Typically, viral load tests are done every 3–6 months if you’re stable on treatment, but more frequent testing may be recommended if you’re newly diagnosed, have side effects, or experience changes in symptoms.
What do my results mean?
Results below the detectable threshold (often labeled as ‘not detected’ or ‘undetectable’) mean the virus is likely suppressed by your treatment. Results above this threshold indicate active virus and may prompt further evaluation, including adjustments to your medication or additional tests.
Can lifestyle factors affect this test?
While lifestyle factors like diet, exercise, or stress can influence overall health, they rarely directly impact viral load measurements. However, poor adherence to medications or untreated conditions (like untreated infections) may temporarily raise viral load. Always follow your provider’s instructions for medication timing.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy