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Official Description

Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, includes reverse transcription, when performed, and amplified probe technique, each type or subtype

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 87501 refers to a diagnostic test that detects the presence of influenza virus by analyzing nucleic acids, specifically DNA or RNA. This test is crucial for identifying the specific type or subtype of influenza present in a laboratory specimen. Influenza viruses are categorized into two main types: type A and type B, each of which can be further divided into various subtypes. For instance, type A includes subtypes such as H1N1, H3N2, and H5N1. The process of nucleic acid detection involves extracting the genetic material from the specimen, which may include blood or other bodily fluids. The test utilizes reverse transcription, if applicable, along with an amplified probe technique to accurately identify the influenza virus. The method typically employed is reverse transcription polymerase chain reaction (RT-PCR), which amplifies the extracted DNA or RNA from specific strains of the influenza virus. This amplification allows for the sizing and analysis of the genetic fragments, leading to the identification of the specific types or subtypes of influenza present. For billing purposes, CPT® Code 87501 is used for each individual type or subtype detected, while multiplex testing for the first two types or subtypes is coded with 87502, and any additional types or subtypes beyond the first two are coded with 87503.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The CPT® Code 87501 is indicated for the detection of the influenza virus in patients presenting with symptoms consistent with influenza infection. This includes, but is not limited to, the following conditions:

  • Influenza-like Illness Symptoms such as fever, cough, sore throat, body aches, and fatigue that suggest a possible influenza infection.
  • Confirmed Exposure Situations where a patient has been in close contact with an individual diagnosed with influenza, warranting testing to confirm or rule out infection.
  • High-Risk Populations Testing may be indicated for individuals in high-risk groups, such as the elderly, young children, or those with compromised immune systems, who may experience severe complications from influenza.

2. Procedure

The procedure for CPT® Code 87501 involves several key steps to ensure accurate detection of the influenza virus:

  • Specimen Collection A sample is collected from the patient, which may include respiratory secretions, blood, or other bodily fluids. The choice of specimen is critical for the accuracy of the test.
  • Nucleic Acid Extraction The collected specimen undergoes a process to extract nucleic acids (DNA or RNA). This step is essential for isolating the genetic material of the influenza virus from the sample.
  • Reverse Transcription (if performed) If applicable, reverse transcription is conducted to convert RNA into complementary DNA (cDNA). This step is crucial for the amplification process that follows.
  • Amplification The extracted nucleic acids are then amplified using polymerase chain reaction (PCR) techniques. This amplification increases the quantity of the viral genetic material, making it easier to detect.
  • Analysis The amplified DNA or RNA fragments are sized and analyzed to identify the specific type or subtype of the influenza virus present in the specimen. This analysis is critical for determining the appropriate clinical response.

3. Post-Procedure

After the completion of the procedure associated with CPT® Code 87501, the laboratory will provide results that indicate the presence or absence of the influenza virus and specify the type or subtype identified. Clinicians should interpret these results in conjunction with the patient's clinical presentation and history. Depending on the findings, further clinical management may be required, including antiviral treatment or additional testing. It is also important to document the results and any subsequent actions taken in the patient's medical record to ensure continuity of care and compliance with reporting requirements.

Short Descr INFLUENZA DNA AMP PROB 1+
Medium Descr INFECTIOUS AGENT DNA/RNA INFLUENZA EA TYPE
Long Descr Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, includes reverse transcription, when performed, and amplified probe technique, each type or subtype
Status Code Statutory Exclusion (from MPFS, may be paid under other methodologies)
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 9 - Not Applicable
Multiple Procedures (51) 9 - Concept does not apply.
Bilateral Surgery (50) 9 - Concept does not apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 9 - Concept does not apply.
Co-Surgeons (62) 9 - Concept does not apply.
Team Surgery (66) 9 - Concept does not apply.
Diagnostic Imaging Family 99 - Concept Does Not Apply
CLIA Waived (QW) No
APC Status Indicator Conditionally packaged laboratory tests
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE 1
CCS Clinical Classification 206 - Microscopic examination (bacterial smear, culture, toxicology)
90 Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
91 Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient.
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GW Service not related to the hospice patient's terminal condition
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
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2015-01-01 Changed Description Changed
2011-01-01 Added Added
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