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ICD-10-CM 2027 diagnosis code

B34.1Enterovirus infection, unspecified

✓ Billable / specific

B34.1 is a valid, billable ICD-10-CM code for enterovirus infection, unspecified. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Looking up by condition? See ICD-10 code for Coxsackie, ICD-10 code for Enterovirus infection.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About B34.1

B34.1 is the ICD-10-CM diagnosis code for enterovirus infection, unspecified. It belongs to category B34 (viral infection of unspecified site), block B25-B34 (other viral diseases) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within B34, choose B34.1 (Enterovirus infection, unspecified) only when documentation doesn't support a more specific option: adenovirus infection, unspecified (B34.0), coronavirus infection, unspecified (B34.2), Parvovirus infection, unspecified (B34.3), Papovavirus infection, unspecified (B34.4), other viral infections of unspecified site (B34.8) and viral infection, unspecified (B34.9).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 865 (Viral Illness with MCC, relative weight 1.3485) and DRG 866 (Viral Illness without MCC, relative weight 0.8692), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 074.8 (other specified diseases due to Coxsackie virus) and 079.89 (other specified viral infection).

Coding notes

Applicable toConditions and synonyms classified to this code
  • Coxsackievirus infection NOS
  • Echovirus infection NOS

Notes that apply from higher levels

Instructions written at a parent level also apply to B34.1.

› From B34 Viral infection of unspecified site
Excludes1
  • anogenital human papillomavirus infection (A63.0)
  • cytomegaloviral disease NOS (B25.9)
  • herpesvirus [herpes simplex] infection NOS (B00.9)
  • retrovirus infection NOS (B33.3)
  • viral agents as the cause of diseases classified elsewhere (B97.-)
  • viral warts due to human papillomavirus infection (B07)

Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.

Alphabetic index entries

9 entries

Terms in the official ICD-10-CM index that lead to B34.1.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

MDC 18 · Infectious and Parasitic Diseases, Systemic or Unspecified Sites

ICD-9-CM equivalent

Converter →
  • 074.8Other specified diseases due to Coxsackie virusapproximate
  • 079.89Other specified viral infectionapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about B34.1

Is B34.1 billable?

Yes. B34.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can B34.1 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict B34.1 as a principal diagnosis.

Is B34.1 a CC or MCC?

No. B34.1 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does B34.1 group to?

B34.1 is used in the MS-DRG v44.0 logic for MS-DRG 865 (Viral Illness with MCC) and MS-DRG 866 (Viral Illness without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for B34.1?

The CMS General Equivalence Mappings map B34.1 to ICD-9-CM 074.8 and 079.89.