Skip to content
Dx

ICD-10-CM 2027 diagnosis code

B34Viral infection of unspecified site

Not billable — use a more specific code

B34 is a header code, so it can't be reported by itself. Choose one of the 7 more specific codes beneath it.

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

B34 is the ICD-10-CM diagnosis code for viral infection of unspecified site. It belongs to block B25-B34 (other viral diseases) and chapter 1 (certain infectious and parasitic diseases). It is a header code, so it can't be reported by itself; one of its 7 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: B34.0 (unspecified), B34.1 (unspecified), B34.2 (unspecified), B34.3 (unspecified), B34.4 (unspecified), B34.8 (site) and B34.9 (unspecified).

Don't report B34 together with the conditions in its Excludes1 note: anogenital human papillomavirus infection (A63.0), cytomegaloviral disease NOS (B25.9), herpesvirus [herpes simplex] infection NOS (B00.9), retrovirus infection NOS (B33.3) and 2 more.

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

Specific codes under B34

Coding notes

Excludes1Not coded here — never report together with this code
  • 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)

Notes that apply from higher levels

Instructions written at a parent level also apply to B34.

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

Alphabetic index entries

1 entries

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

Codes whose notes reference B34

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

Is B34 billable?

No. B34 is a header code. Report one of its more specific subcodes instead.