SARS-CoV-2 Nucleic Acid Detection by Reverse Transcription Polymerase Chain Reaction (RT-PCR) from Respiratory Specimen
This test checks for the presence of genetic material from the SARS-CoV-2 virus, which causes COVID-19, in your respiratory sample (e.g., nasal or throat swab). It helps determine if you have an active infection.
["This test helps doctors diagnose COVID-19 by detecting the virus’s genetic material in your sample."]
Key facts at a glance
- LOINC
- 94645-9
- Short code
- SARS-CoV-2 RdRp Ct Spec Qn NAA+probe
- Synonyms
- SARS-CoV-2 RdRp Ct Spec Qn 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
- 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
How the Test Works
The test uses a process called reverse transcription polymerase chain reaction (RT-PCR) to identify the virus’s genetic material. A swab is collected from your nose or throat, and the sample is analyzed in a lab to detect specific sequences unique to SARS-CoV-2.
What to Expect Before the Test
You may have no symptoms before testing, but if you’re experiencing respiratory issues, fever, cough, or shortness of breath, inform your healthcare provider. Avoid smoking or using nasal sprays 15–30 minutes before testing to ensure accurate results.
What to Expect During the Test
The test involves a quick, painless swab of your nasal or throat passage. You may feel mild discomfort, but it usually lasts only a few seconds. No special preparation is needed beyond what your provider advises.
When Results Are Available
Results are typically available within 24–72 hours, depending on lab processing times. Your healthcare provider will discuss the results with you directly.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
SARS-CoV-2 RT-PCR Test
Frequently asked questions
This test is critical for diagnosing COVID-19, guiding treatment decisions, and monitoring infection spread. Positive results indicate an active viral infection, while negative results suggest no detectable virus at the time of testing (though reinfection is possible).
You could have an asymptomatic infection, meaning you may spread the virus without realizing it. Some people test positive for a short time after exposure before symptoms appear. Always follow public health guidelines for isolation if positive.
No, this test only detects active SARS-CoV-2 infection by looking for the virus’s genetic material. For evidence of past infection, antibody tests (e.g., serology) are used.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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