2027 ICD-10-CM Diagnosis Code A01.01Typhoid meningitis

ICD-10-CM Codes›A00–B99›A00-A09›A01

ICD-10-CM A01.01
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A01.01 is a billable ICD-10-CM diagnosis code for typhoid meningitis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 867 through 869. 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 11 closely related codes. Coders also document this condition as meningitis due to typhoid fever. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Meningitis.

Code Identity

ICD-10-CM Code
A01.01
Billable Status
Yes — Valid for Submission
Code Describes
Typhoid meningitis
Short Description
Typhoid meningitis
Same as the full description in the CMS dataset.
Parent Code
A01.0
Typhoid fever

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA01Typhoid and paratyphoid fevers
This CodeA01.01Typhoid meningitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Meningitis due to typhoid fever
  • Salmonella meningitis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A01.01: its own notes plus those printed at 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

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.-)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A01.01, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming A01.01: its condition is not part of those codes, and both may be reported when the patient has both.

  • Block P35-P39 Infections specific to the perinatal period
    intestinal infectious disease (A00-A09) names A00-A09, which includes this code
  • P37 Other congenital infectious and parasitic diseases
    infectious neonatal diarrhea (A00-A09) names A00-A09, which includes this code

Code First 1

These codes say to code first a condition named in the note, and A01.01 is one of the conditions named.

  • M49 Spondylopathies in diseases classified elsewhere
    enterobacterial infections (A01-A04) names A01-A04, which includes this code

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 INF003
Bacterial infections
Default principal diagnosis: inpatient No · outpatient No
CCSR NVS001
Meningitis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Typhoid Fever

    an acute systemic febrile infection caused by salmonella typhi, a serotype of salmonella enterica.

Patient EducationClinical

Meningitis

Meningitis is inflammation of the thin tissue that surrounds the brain and spinal cord, called the meninges. There are several types of meningitis. The most common is viral meningitis. You get it when a virus enters the body through the nose or mouth and travels to the brain. Bacterial meningitis is rare but can be deadly.

Read the full article at MedlinePlus

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

Convert A01.01 to ICD-9-CMHistory

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

ICD-9-CM
002.0 Typhoid fever
Approximate The match is approximate rather than exact.

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 A01.01Overview

What is the ICD-10 code for typhoid meningitis?

The ICD-10-CM code for typhoid meningitis is A01.01 (sometimes written as A0101). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A01.01 (Typhoid fever) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report typhoid meningitis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does A01.01 group to?

When typhoid meningitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 869, 868, with relative weights from 0.6784 to 2.1855 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A01.01 a CC or MCC?

CMS lists A01.01 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 11 closely related codes in its exclusion list.

What is the ICD-9 equivalent of A01.01?

Under the General Equivalence Mappings, typhoid meningitis converts to ICD-9-CM 002.0 (typhoid fever). The mapping is approximate, so confirm the match fits the documentation.