2026 ICD-10-CM Diagnosis Code B97.4Respiratory syncytial virus as the cause of diseases classified elsewhere

ICD-10-CM CodesA00–B99B95-B97B97

ICD-10-CM B97.4
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B97.4 is a billable ICD-10-CM diagnosis code for respiratory syncytial virus as the cause of diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 865 through 866. The code is not accepted as a principal diagnosis by the Medicare Code Editor. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Viral infection.

Code Identity

ICD-10-CM Code
B97.4
Billable Status
Yes — Valid for Submission
Code Describes
Respiratory syncytial virus as the cause of diseases classified elsewhere
Short Description
Respiratory syncytial virus causing diseases classd elswhr
Parent Code
Viral agents as the cause of diseases classified elsewhere

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB95-B97Bacterial and viral infectious agents
CategoryB97Viral agents as the cause of diseases classified elsewhere
This CodeB97.4Respiratory syncytial virus as the cause of diseases classified elsewhere

Code EditsBilling

Medicare Code Editor checks that affect claim validity for B97.4.

There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute lower respiratory infection caused by respiratory syncytial virus
  • Acute nasopharyngitis caused by respiratory syncytial virus
  • Acute upper respiratory infection caused by respiratory syncytial virus
  • Acute viral pharyngitis
  • Death associated with respiratory syncytial virus infection
  • Healthcare associated respiratory syncytial virus disease
  • Paramyxoviridae encephalitis
  • Respiratory syncytial virus encephalitis
  • Respiratory syncytial virus infection
  • Respiratory syncytial virus pharyngitis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • RSV as the cause of diseases classified elsewhere

Code First

  • related disorders, such as:
  • otitis media H65
  • upper respiratory infection J06.9

Type 1 Excludes

  • acute bronchiolitis due to respiratory syncytial virus RSV J21.0
  • acute bronchitis due to respiratory syncytial virus RSV J20.5
  • respiratory syncytial virus RSV pneumonia J12.1

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Infection, infected, infective(opportunistic)
      • virus, viral NOS
        • respiratory syncytial (RSV)
          • as cause of disease classified elsewhere
    • Respiratory
      • syncytial virus, as cause of disease classified elsewhere
    • Virus, viral
      • respiratory syncytial (RSV)
        • as cause of disease classified elsewhere

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Respiratory Syncytial Virus Infections

Respiratory syncytial virus, or RSV, is a common respiratory virus. It usually causes mild, cold-like symptoms. But it can cause serious lung infections, especially in infants, older adults, and people with serious medical problems.

The full article covers:

  • What is respiratory syncytial virus (RSV)?
  • How is respiratory syncytial virus (RSV) spread?
  • Who is at risk for respiratory syncytial virus (RSV) infections?
  • What are the symptoms of respiratory syncytial virus (RSV) infections?
  • How are respiratory syncytial virus (RSV) infections diagnosed?
  • What are the treatments for respiratory syncytial virus (RSV) infections?
  • Can respiratory syncytial virus (RSV) infections be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert B97.4 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
079.6 Resprtry syncytial virus
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About B97.4Overview

Is B97.4 (Viral agents as the cause of diseases classified elsewhere) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report respiratory syncytial virus as the cause of diseases classified elsewhere on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does B97.4 group to?

On inpatient claims, respiratory syncytial virus as the cause of diseases classified elsewhere maps to MS-DRG 865, 866, with relative weights from 0.8696 to 1.4983 depending on complications. Higher weights mean higher Medicare reimbursement.

Can B97.4 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because respiratory syncytial virus as the cause of diseases classified elsewhere describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

What is the ICD-9 equivalent of B97.4?

Under the General Equivalence Mappings, respiratory syncytial virus as the cause of diseases classified elsewhere converts to ICD-9-CM 079.6 (resprtry syncytial virus). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.