ICD-10-CM 2027 diagnosis code
A94Unspecified arthropod-borne viral fever
A94 is a valid, billable ICD-10-CM code for unspecified arthropod-borne viral fever. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
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 A94
A94 is the ICD-10-CM diagnosis code for unspecified arthropod-borne viral fever. It belongs to block A90-A99 (arthropod-borne viral fevers and viral hemorrhagic fevers) 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.
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
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 066.9 (arthropod-borne viral disease, unspecified).
Coding notes
- Arboviral fever NOS
- Arbovirus infection NOS
Notes that apply from higher levels
Instructions written at a parent level also apply to A94.
Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.
Alphabetic index entries
8 entriesTerms in the official ICD-10-CM index that lead to A94.
- Disease, diseased › arthropod-borne NOS (viral)
- Disease, diseased › viral, virus › arbovirus NOS
- Disease, diseased › viral, virus › arthropod-borne NOS
- Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) › arbovirus, arboviral
- Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) › arbovirus, arboviral › hemorrhagic
- Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) › hemorrhagic (arthropod-borne) NOS
- Infection, infected, infective (opportunistic) › arbovirus (arbor virus)
- Infection, infected, infective (opportunistic) › virus, viral NOS › arborvirus, arbovirus arthropod-borne
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 →- 066.9Arthropod-borne viral disease, unspecifiedapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about A94
Is A94 billable?
- Yes. A94 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A94 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A94 as a principal diagnosis.
Is A94 a CC or MCC?
- A94 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does A94 group to?
- A94 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 A94?
- The CMS General Equivalence Mappings map A94 to ICD-9-CM 066.9.