2027 ICD-10-CM Diagnosis Code B34.9Viral infection, unspecified
ICD-10-CM Codes›A00–B99›B25-B34›B34
- Billable — Valid for Submission
- Not Chronic
B34.9 is a billable ICD-10-CM diagnosis code for viral 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Viral infection.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Acute infectious tubulointerstitial nephritis
- Acute infective otitis externa
- Acute pyelonephritis
- Acute tubulointerstitial nephritis
- Acute viral disease
- Acute viral otitis externa
- Acute viral tubulointerstitial nephritis
- Alanine aminotransferase level within reference range
- Alanine aminotransferase within reference range with persistent viremia by polymerase chain reaction
- Amantadine resistant virus present
- Arthropathy associated with viral disease
- Asymptomatic viremia
- Autoimmune lymphoproliferative syndrome with recurrent viral infection
- Bilateral infective arthritis of hands
- Bilateral infective arthritis of hips
- Bilateral infective arthritis of knees
- Bilateral infective arthritis of wrist regions
- Bilateral viral arthritis of ankle joints
- Bilateral viral arthritis of joint of hands
- Bilateral viral arthritis of knee joints
- Bilateral viral arthritis of shoulder region joints
- Bilateral viral arthritis of wrist joints
- Chronic viral otitis externa
- Gingival disease caused by virus
- Illness
- Inconclusive evaluation finding
- Infection caused by antimicrobial resistant virus
- Infection involving inner ear
- Infectious panuveitis
- Infective arthritis of bilateral feet caused by virus
- Infective arthritis of bilateral hips caused by virus
- Infective arthritis of foot caused by virus
- Infective arthritis of hip caused by virus
- Infective arthritis of joint of bilateral shoulder regions
- Infective arthritis of joint of left shoulder region
- Infective arthritis of joint of right shoulder region
- Infective arthritis of left ankle
- Infective arthritis of left foot
- Infective arthritis of left foot caused by virus
- Infective arthritis of left hip
- Infective arthritis of left hip caused by virus
- Infective arthritis of left wrist
- Infective arthritis of right ankle
- Infective arthritis of right foot
- Infective arthritis of right foot caused by virus
- Infective arthritis of right hip
- Infective arthritis of right hip caused by virus
- Infective arthritis of right wrist
- Infective polyarthritis
- Influenza-like illness
- Invasive viral infectious disease
- Labyrinthitis of bilateral inner ears
- Labyrinthitis of left inner ear
- Labyrinthitis of right inner ear
- Liver enzymes within reference range
- Maternal postpartum viral disease
- Neonatal dacryocystitis or conjunctivitis caused by virus
- Neonatal hyperbilirubinemia due to viral infection
- Neonatal viral infection of skin
- Oseltamivir resistant virus present
- Panuveitis caused by virus
- Polyarticular viral arthritis
- Recurrent infection caused by virus
- Sepsis caused by virus
- Sustained viral response
- Viral arthritis co-occurrent with hepatitis
- Viral arthritis of hand
- Viral arthritis of joint of left ankle
- Viral arthritis of joint of left hand
- Viral arthritis of joint of left knee
- Viral arthritis of joint of right ankle
- Viral arthritis of joint of right hand
- Viral arthritis of joint of right knee
- Viral arthritis of knee
- Viral cardiovascular infection
- Viral corneal ulcer
- Viral disease
- Viral disease in mother complicating childbirth
- Viral ear infection
- Viral esophagitis
- Viral eye infection
- Viral fever
- Viral gastritis
- Viral headache
- Viral infection of peripheral nerve
- Viral kidney infection
- Viral labyrinthitis
- Viral labyrinthitis of bilateral inner ears
- Viral labyrinthitis of left inner ear
- Viral labyrinthitis of right inner ear
- Viral lower respiratory infection
- Viral musculoskeletal infection
- Viral myalgia
- Viral myositis
- Viral pharyngitis
- Viral pleurisy
- Viral posterior uveitis
- Viral sinusitis
- Viral syndrome
- Viremia
- Virus inconclusive
- Virus present
- Virus-associated atypical lymphoproliferative disorder
- Zanamivir resistant virus present
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to B34.9: 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.
- diseases generally recognized as communicable or transmissible
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Viremia NOS
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
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.
- 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.
- 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 B34.9, its category, or a range that includes it.
Applicable To 1
These notes mention B34.9.
- O98.5 Other viral diseases complicating pregnancy, childbirth and the puerperium
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disease, diseased See Also: Syndrome;
Viremia B34.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Virus Diseases
a general term for diseases caused by viruses.
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 B34.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About B34.9Overview
What is the ICD-10 code for viral infection, unspecified?
The ICD-10-CM code for viral infection, unspecified is B34.9 (sometimes written as B349). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is B34.9 (Viral infection of unspecified site) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report viral infection, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does B34.9 group to?
When viral 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 B34.9 be reported with A63.0?
Not as a rule. The Excludes1 note at B34, which applies to B34.9, 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 B34.9?
Under the General Equivalence Mappings, viral infection, unspecified converts to ICD-9-CM 790.8 (viremia NOS). The mapping is approximate, so confirm the match fits the documentation.
