2027 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 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A80.9 is a billable ICD-10-CM diagnosis code for acute poliomyelitis, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 23 through 24, 97 through 99. 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 cervical spine due to and following poliomyelitis
  • Neuromuscular scoliosis of cervicothoracic spine
  • Neuromuscular scoliosis of lumbar spine
  • Neuromuscular scoliosis of lumbar spine due to poliomyelitis
  • Neuromuscular scoliosis of thoracic spine
  • Neuromuscular scoliosis of thoracic spine due to poliomyelitis
  • Polioencephalitis
  • Polioencephalopathy
  • Scoliosis due to and following infection
  • Scoliosis of cervical spine

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A80.9: its own notes plus those printed at A80, block A80-A89, and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From A80 Acute poliomyelitis applies to 7 codes
  • acute flaccid myelitis (G04.82)
From Block A80-A89 Viral and prion infections of the central nervous system applies to 48 codes
  • postpolio syndrome (G14)
  • sequelae of poliomyelitis (B91)
  • sequelae of viral encephalitis (B94.1)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A80.9, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming A80.9: they are not reported together with it, unless the two conditions are unrelated.

  • A85 Other viral encephalitis, not elsewhere classified
    encephalitis due to poliomyelitis virus (A80.-) names A80.-, which includes this code
  • A87 Viral meningitis
    meningitis due to poliomyelitis virus (A80.-) names A80.-, which includes this code

Code First 2

These codes say to code first a condition named in the note, and A80.9 is one of the conditions named.

  • G02 Meningitis in other infectious and parasitic diseases classified elsewhere
    poliovirus infection (A80.-) names A80.-, which includes this code
  • G05 Encephalitis, myelitis and encephalomyelitis in diseases classified elsewhere
    poliovirus (A80.-) names A80.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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

Clinical InformationClinical

  • Poliomyelitis

    an acute infectious disease of humans, particularly children, caused by any of three serotypes of human poliovirus (poliovirus). usually the infection is limited to the gastrointestinal tract and nasopharynx, and is often asymptomatic. the central nervous system, primarily the spinal cord, may be affected, leading to rapidly progressive paralysis, coarse fasciculation and hyporeflexia. motor neurons are primarily affected. encephalitis may also occur. the virus replicates in the nervous system, and may cause significant neuronal loss, most notably in the spinal cord. a rare related condition, nonpoliovirus poliomyelitis, may result from infections with nonpoliovirus enteroviruses. (from adams et al., principles of neurology, 6th ed, pp764-5)

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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About A80.9Overview

What is the ICD-10 code for acute poliomyelitis, unspecified?

The ICD-10-CM code for acute poliomyelitis, unspecified is A80.9 (sometimes written as A809). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

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, 2026 through September 30, 2027.

What MS-DRG does A80.9 group to?

When acute poliomyelitis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 24, 98, 99, 23, 97, with relative weights from 1.5249 to 5.7422 depending on complications. Higher weights mean higher Medicare reimbursement.

Can A80.9 be reported with G04.82?

Not as a rule. The Excludes1 note at A80, which applies to A80.9, lists "acute flaccid myelitis (G04.82)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

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.