Skip to content
HCC Buddy home

HCC Buddy Code Book

Skip to code book content
HCC Buddy
HCC Buddy
Alphabetic Index and Tabular path
HCC Buddy public API, FY2026 Apr updateSource load source requiredSource year 2026Updated 2026-04-01

Index trail

Western equine encephalitis

See Tabular List: A83.1

A83, Mosquito-borne viral encephalitis

A83.1, Western equine encephalitis

Selected code, source checked for the selected effective period

Commonly confused codes

official source

Not listed for this effective period.

Code details and official notes

A83.1

Western equine encephalitis

Open the shareable code page for A83.1→
billable

Includes

official source
  • mosquito-borne viral meningoencephalitis

Excludes 1

official source

No Excludes 1 note is listed in this source payload.

Excludes 2

official source
  • Venezuelan equine encephalitis (A92.2)
  • West Nile fever (A92.3-)
  • West Nile virus (A92.3-)

Code First

official source

Not listed for this effective period.

Use Additional

official source

Not listed for this effective period.

Code Also

official source

Not listed for this effective period.

7th character

official source

Not listed for this code in the selected Tabular payload.

Placeholder X

official source

Not listed for this code in the selected Tabular payload.

Laterality

official source

No laterality instruction is listed for this code in the selected Tabular payload.

Effective period

source required
  • FY2026 Apr update
  • Source year 2026
  • Updated 2026-04-01
  • HCC Buddy public API
HCC Buddy
HCC Buddy
Alphabetic Index and Tabular path
HCC Buddy public API, FY2026 Apr updateSource load source requiredSource year 2026Updated 2026-04-01

Index trail

Western equine encephalitis

See Tabular List: A83.1

A83, Mosquito-borne viral encephalitis

A83.1, Western equine encephalitis

Selected code, source checked for the selected effective period

Commonly confused codes

official source

Not listed for this effective period.

Code details and official notes

A83.1

Western equine encephalitis

Open the shareable code page for A83.1→
billable

Includes

official source
  • mosquito-borne viral meningoencephalitis

Excludes 1

official source

No Excludes 1 note is listed in this source payload.

Excludes 2

official source
  • Venezuelan equine encephalitis (A92.2)
  • West Nile fever (A92.3-)
  • West Nile virus (A92.3-)

Code First

official source

Not listed for this effective period.

Use Additional

official source

Not listed for this effective period.

Code Also

official source

Not listed for this effective period.

7th character

official source

Not listed for this code in the selected Tabular payload.

Placeholder X

official source

Not listed for this code in the selected Tabular payload.

Laterality

official source

No laterality instruction is listed for this code in the selected Tabular payload.

Effective period

source required
  • FY2026 Apr update
  • Source year 2026
  • Updated 2026-04-01
  • HCC Buddy public API
HCC Buddy Insights

HCC Mapping

V28 source requiredV24 source requiredRxHCC source requiredESRD/PACE source requiredHCC 3 HHS-HCC 3; HHS-HCC 2026 benefit year (HHS-HCC)

RAF Value

V28 RAF source requiredV24 RAF source requiredRxHCC RAF source requiredESRD/PACE RAF source requiredHHS-HCC: RAF: Varies by metal level

Model Period

FY2026 Apr update

Source

source required

Audit Caution

Close codes need documentation support before selection. Do not assume relationships.
Reviewed by Jess P., CPC

HCC Buddy workflow band

HCC mapping, RAF, MEAT, source trail, and audit caution stay in view.

MEAT supportaudit cautionsource required

HHS-HCC

HCC 3

HHS-HCC 3; HHS-HCC 2026 benefit year

RAF: Varies by metal level

MEAT checklist

Reviewed by Jess P., CPC

Monitor, Evaluate, Assess, or Treat must be supported in the provider note.

HCC Buddy guidance, not official ICD-10-CM text.

Audit caution

Reviewed by Jess P., CPC

Close codes need documentation support before selection. Do not assume relationships.

HCC Buddy guidance, not official ICD-10-CM text.

Reviewer sign-off

Reviewed by Jess P., CPC

MEAT, documentation support, audit cautions, and close-code guidance are reviewed and approved for this effective period.

HCC Buddy enrichment is separate from official source text.

Last updated: April 1, 2026 · Not a substitute for official coding guidelines. No PHI or patient data.
HCC Buddy Code Card
FY 2026 Apr update
A83.1Billable

Western equine encephalitis

ACA/HHS

HCC 3

RAF Varies by metal level

Reviewed by Jess P., CPCFY2026 Apr update

Code

A83.1

V28 HCC

Not mapped

RAF

source required

Compare tray

Add close codes to compare documentation differences.