2027 ICD-10-CM Diagnosis Code B97.35Human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere

ICD-10-CM Codes›A00–B99›B95-B97›B97

ICD-10-CM B97.35
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

B97.35 is a billable ICD-10-CM diagnosis code for human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere. 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. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 9 closely related codes. The code is not accepted as a principal diagnosis by the Medicare Code Editor. Coders also document this condition as encephalitis caused by human immunodeficiency virus type 2. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under HIV infection.

For Medicare Advantage risk adjustment, B97.35 maps to CMS-HCC Category 1 (HIV/AIDS) under the V28 model, adding a risk factor of about 0.301 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
B97.35
Billable Status
Yes — Valid for Submission
Code Describes
Human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere
Short Description
HIV 2 as the cause of diseases classified elsewhere
Parent Code
B97.3
Retrovirus as the cause of diseases classified elsewhere

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB95-B97Bacterial and viral infectious agents
CategoryB97Viral agents as the cause of diseases classified elsewhere
This CodeB97.35Human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere

Code EditsBilling

Medicare Code Editor checks that affect claim validity for B97.35.

Unacceptable principal diagnosis
There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Medicare Risk Adjustment (HCC)Billing

B97.35 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 1— HIV/AIDS
Payment HCC · PY 2027 one of 3 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.301
community, non-dual, aged · ranges 0.109–1.322 across segments
Hierarchy
Top of its hierarchy
HCC 1 is not superseded by any other condition category
Prior Model (CMS-HCC V24)
HCC 1
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 1 · ESRD (V21): HCC 1 · ESRD (V24): HCC 1
ESRD V21 weights: 0.154 dialysis, 0.350–1.708 functioning graft · ESRD V24 weights: 0.122 dialysis, 0.292–1.302 functioning graft
Part D (RxHCC)
RxHCC 1 — HIV/AIDS
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Encephalitis caused by human immunodeficiency virus type 2
  • Human immunodeficiency virus encephalitis
  • Human immunodeficiency virus II infection
  • Retroviridae encephalitis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to B97.35: its own notes plus those printed at B97.3, block B95-B97, 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 B97.3 Retrovirus as the cause of diseases classified elsewhere applies to 7 codes
  • Human immunodeficiency virus [HIV] disease (B20)

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.-)

Notes

General instructions on how these codes are used.

From Block B95-B97 Bacterial and viral infectious agents applies to 46 codes
  • These categories are provided for use as supplementary or additional codes to identify the infectious agent(s) in diseases classified elsewhere.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name B97.35, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming B97.35: they are not reported together with it, unless the two conditions are unrelated.

  • B34 Viral infection of unspecified site
    viral agents as the cause of diseases classified elsewhere (B97.-) names B97.-, which includes this code

Use Additional Code 52

These codes say to use an additional code from the note, and B97.35 is one of the codes named.

  • J95.851 Ventilator associated pneumonia
    code to identify the organism, if known (B95.-, B96.-, B97.-) names B97.-, which includes this code
  • P23.0 Congenital pneumonia due to viral agent
    code (B97) to identify organism names B97, which includes this code
  • E06.0 Acute thyroiditis
    code (B95-B97) to identify infectious agent. names B95-B97, which includes this code
  • G06 Intracranial and intraspinal abscess and granuloma
    code (B95-B97) to identify infectious agent. names B95-B97, which includes this code
  • H65 Nonsuppurative otitis media
    infectious agent (B95-B97) names B95-B97, which includes this code
  • I30.1 Infective pericarditis
    code (B95-B97) to identify infectious agent names B95-B97, which includes this code
  • I33.0 Acute and subacute infective endocarditis
    code (B95-B97) to identify infectious agent names B95-B97, which includes this code
  • I40.0 Infective myocarditis
    code (B95-B97) to identify infectious agent names B95-B97, which includes this code
  • J01 Acute sinusitis
    code (B95-B97) to identify infectious agent. names B95-B97, which includes this code
  • J02.8 Acute pharyngitis due to other specified organisms
    code (B95-B97) to identify infectious agent names B95-B97, which includes this code
  • J03.8 Acute tonsillitis due to other specified organisms
    code (B95-B97) to identify infectious agent. names B95-B97, which includes this code
  • J04 Acute laryngitis and tracheitis
    code (B95-B97) to identify infectious agent. names B95-B97, which includes this code
  • J05 Acute obstructive laryngitis [croup] and epiglottitis
    code (B95-B97) to identify infectious agent. names B95-B97, which includes this code
  • J06.9 Acute upper respiratory infection, unspecified
    code (B95-B97) to identify infectious agent, if known, such as: names B95-B97, which includes this code
  • J32 Chronic sinusitis
    infectious agent (B95-B97) names B95-B97, which includes this code

37 more Use Additional Code notes name this code. Browse all Use Additional Code notes.

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 INF006
HIV infection
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

HIV

HIV stands for human immunodeficiency virus. HIV harms your immune system by destroying a type of white blood cell that helps your body fight infection. This puts you at risk for other infections and diseases.

The full article covers:

  • What is HIV?
  • What is AIDS?
  • How does HIV spread?
  • Who is at risk for HIV infection?
  • What are the symptoms of HIV?
  • How do I know if I have HIV?
  • What are the treatments for HIV?
  • Can HIV infection be prevented?

Read the full article at MedlinePlus

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

Convert B97.35 to ICD-9-CMHistory

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

ICD-9-CM
079.53 Hiv-2 infection oth dis
Exact Match The mapping is direct, with no qualifiers.

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 B97.35Overview

Is B97.35 (Retrovirus as the cause of diseases classified elsewhere) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does B97.35 group to?

On inpatient claims, human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere maps to MS-DRG 866, 865, with relative weights from 0.8691 to 1.3153 depending on complications. Higher weights mean higher Medicare reimbursement.

Is B97.35 a CC or MCC?

CMS lists B97.35 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 9 closely related codes in its exclusion list.

Can B97.35 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

Can B97.35 be reported with B20?

Not as a rule. The Excludes1 note at B97.3, which applies to B97.35, lists "Human immunodeficiency virus [HIV] disease (B20)". 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 HCC is B97.35?

B97.35 (human immunodeficiency virus, type 2 [HIV 2] as the cause of diseases classified elsewhere) maps to CMS-HCC Category 1 (HIV/AIDS), commonly written as HCC 1, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 1 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 1.

Does B97.35 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, B97.35 adds a risk adjustment factor of about 0.301 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.109 to 1.322 depending on the payment segment). HCC 1 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 1 category page.