2027 ICD-10-CM Diagnosis Code B34.0Adenovirus infection, unspecified

ICD-10-CM Codes›A00–B99›B25-B34›B34

ICD-10-CM B34.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

B34.0 is a billable ICD-10-CM diagnosis code for adenovirus infection, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 865 through 866. Coders also document this condition as adenovirus infection in immunocompromised person. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Viral infection.

Code Identity

ICD-10-CM Code
B34.0
Billable Status
Yes — Valid for Submission
Code Describes
Adenovirus infection, unspecified
Short Description
Adenovirus infection, unspecified
Same as the full description in the CMS dataset.
Parent Code
B34
Viral infection of unspecified site

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB25-B34Other viral diseases
CategoryB34Viral infection of unspecified site
This CodeB34.0Adenovirus infection, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Adenovirus infection in immunocompromised person
  • Human adenovirus present
  • Patient immunocompromised
  • Simian adenovirus infection

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to B34.0: its own notes plus those printed at B34 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 B34 Viral infection of unspecified site applies to 7 codes
  • 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)

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 B34.0, its category, or a range that includes it.

Applicable To 1

These notes mention B34.0.

  • O98.5 Other viral diseases complicating pregnancy, childbirth and the puerperium
    Conditions in A80-B09, B25-B34, R87.81-, R87.82- names B25-B34, 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 INF008
Viral infection
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Adenoviridae Infections

    virus diseases caused by the adenoviridae.

Patient EducationClinical

Viral Infections

Viruses are very tiny germs. They are made of genetic material (either DNA or RNA) inside of a protein coating. There are a huge number of viruses on earth. Only a small number of them can infect humans. Those viruses can infect our cells, which may cause disease.

The full article covers:

  • What are viruses?
  • How are viruses spread?
  • How do viruses cause disease?
  • What are the treatments for viral infections?
  • Can viral infections be prevented?

Read the full article at MedlinePlus

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

Convert B34.0 to ICD-9-CMHistory

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

ICD-9-CM
079.0 Adenovirus infect 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 B34.0Overview

What is the ICD-10 code for adenovirus infection, unspecified?

The ICD-10-CM code for adenovirus infection, unspecified is B34.0 (sometimes written as B340). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is B34.0 (Viral infection of unspecified site) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report adenovirus infection, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does B34.0 group to?

When adenovirus infection, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 866, 865, with relative weights from 0.8691 to 1.3153 depending on complications. Higher weights mean higher Medicare reimbursement.

Can B34.0 be reported with A63.0?

Not as a rule. The Excludes1 note at B34, which applies to B34.0, lists "anogenital human papillomavirus infection (A63.0)". 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 B34.0?

Under the General Equivalence Mappings, adenovirus infection, unspecified converts to ICD-9-CM 079.0 (adenovirus infect NOS). The mapping is approximate, so confirm the match fits the documentation.