2027 ICD-10-CM Diagnosis Code A01.4Paratyphoid fever, unspecified

ICD-10-CM Codes›A00–B99›A00-A09›A01

ICD-10-CM A01.4
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A01.4 is a billable ICD-10-CM diagnosis code for paratyphoid fever, unspecified. 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 eruption of skin caused by Salmonella. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Intestinal infection.

Code Identity

ICD-10-CM Code
A01.4
Billable Status
Yes — Valid for Submission
Code Describes
Paratyphoid fever, unspecified
Short Description
Paratyphoid fever, unspecified
Same as the full description in the CMS dataset.
Parent Code
A01
Typhoid and paratyphoid fevers

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA01Typhoid and paratyphoid fevers
This CodeA01.4Paratyphoid fever, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Eruption of skin caused by Salmonella
  • Eruption of skin caused by Salmonella Paratyphi
  • Paratyphoid fever

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A01.4: 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

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Infection due to Salmonella paratyphi NOS

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 A01.4, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming A01.4: 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 2

These codes say to code first a condition named in the note, and A01.4 is one of the conditions named.

  • M01 Direct infections of joint in infectious and parasitic diseases classified elsewhere
    paratyphoid fever (A01.1-A01.4) names A01.1-A01.4, which includes this code
  • 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 DIG001
Intestinal infection
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Paratyphoid Fever

    a prolonged febrile illness commonly caused by several paratyphi serotypes of salmonella enterica. it is similar to typhoid fever but less severe.

Patient EducationClinical

Salmonella Infections

Salmonella is the name of a group of bacteria. In the United States, it is a common cause of foodborne illness. Salmonella occurs in raw poultry, eggs, beef, and sometimes on unwashed fruit and vegetables. You also can get infected after handling pets, especially reptiles like snakes, turtles, and lizards.

Read the full article at MedlinePlus

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

Convert A01.4 to ICD-9-CMHistory

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

ICD-9-CM
002.9 Paratyphoid fever NOS
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 A01.4Overview

What is the ICD-10 code for paratyphoid fever, unspecified?

The ICD-10-CM code for paratyphoid fever, unspecified is A01.4 (sometimes written as A014). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A01.4 (Typhoid and paratyphoid fevers) a billable code?

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

What MS-DRG does A01.4 group to?

When paratyphoid fever, unspecified 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 A01.4 a CC or MCC?

CMS lists A01.4 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 A01.4?

Under the General Equivalence Mappings, paratyphoid fever, unspecified converts to ICD-9-CM 002.9 (paratyphoid fever NOS). The mapping is a direct match.