2026 ICD-10-CM Diagnosis Code A80.9Acute poliomyelitis, unspecified

ICD-10-CM Codes›A00–B99›A80-A89›A80

ICD-10-CM A80.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A80.9 is a billable ICD-10-CM diagnosis code for acute poliomyelitis, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified CNS infection and poliomyelitis and Viral infection.

Code Identity

ICD-10-CM Code
A80.9
Billable Status
Yes — Valid for Submission
Code Describes
Acute poliomyelitis, unspecified
Short Description
Acute poliomyelitis, unspecified
Same as the full description in the CMS dataset.
Parent Code
A80
Acute poliomyelitis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA80-A89Viral and prion infections of the central nervous system
CategoryA80Acute poliomyelitis
This CodeA80.9Acute poliomyelitis, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute poliomyelitis
  • Acute poliomyelitis caused by Human poliovirus 1
  • Cervicothoracic neuromuscular scoliosis due to and following poliomyelitis
  • Infection caused by human poliovirus
  • Late effects of poliomyelitis
  • Meningitis caused by Enterovirus
  • Meningitis caused by Human poliovirus
  • Myelitis caused by Enterovirus
  • Myelitis caused by human poliovirus
  • Neuromuscular scoliosis due to and following poliomyelitis
  • Neuromuscular scoliosis of cervical spine
  • Neuromuscular scoliosis of cervicothoracic spine
  • Neuromuscular scoliosis of thoracic spine
  • Polioencephalitis
  • Polioencephalopathy
  • Scoliosis due to and following infection
  • Scoliosis of cervical spine

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.

    • Encephalitis(chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute)
      • in (due to)
        • poliovirus
    • Heine-Medin disease
    • Meningitis(basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic)
      • in (due to)
        • poliovirus
    • Meningitis(basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic)
      • poliovirus
    • Polioencephalitis(acute) (bulbar)
    • Polioencephalomyelitis(acute) (anterior)
    • Poliomyelitis(acute) (anterior) (epidemic)
    • Poliomyelitis(acute) (anterior) (epidemic)
      • nonepidemic
    • Poliomyelitis(acute) (anterior) (epidemic)
      • spinal, acute

Clinical ClassificationClinical

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

CCSR NVS003
Other specified CNS infection and poliomyelitis
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Polio and Post-Polio Syndrome

Polio, or poliomyelitis, is a disease that spreads from person to person. It is caused by the poliovirus. The virus attacks the nervous system. In serious cases, it can cause paralysis (where you can't move parts of the body). The paralysis may be lifelong and can sometimes be life-threatening.

The full article covers:

  • What is polio?
  • How does polio spread?
  • Who is more likely to develop polio?
  • What are the symptoms of polio?
  • What is post-polio syndrome (PPS)?
  • How is polio diagnosed?
  • What are the treatments for polio and post-polio syndrome (PPS)?
  • Can polio be prevented?

Read the full article at MedlinePlus

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

Convert A80.9 to ICD-9-CMHistory

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

ICD-9-CM
045.90 Ac polio NOS-type NOS
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 A80.9Overview

Is A80.9 (Acute poliomyelitis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute poliomyelitis, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of A80.9?

Under the General Equivalence Mappings, acute poliomyelitis, unspecified converts to ICD-9-CM 045.90 (ac polio NOS-type NOS). 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.