2026 ICD-10-CM Diagnosis Code A75.3Typhus fever due to Rickettsia tsutsugamushi

ICD-10-CM Codes›A00–B99›A75-A79›A75

ICD-10-CM A75.3
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A75.3 is a billable ICD-10-CM diagnosis code for typhus fever due to Rickettsia tsutsugamushi. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 867 through 869. Coders also document this condition as infection caused by Orientia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Parasitic, other specified and unspecified infections.

Code Identity

ICD-10-CM Code
A75.3
Billable Status
Yes — Valid for Submission
Code Describes
Typhus fever due to Rickettsia tsutsugamushi
Short Description
Typhus fever due to Rickettsia tsutsugamushi
Same as the full description in the CMS dataset.
Parent Code
A75
Typhus fever

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA75-A79Rickettsioses
CategoryA75Typhus fever
This CodeA75.3Typhus fever due to Rickettsia tsutsugamushi

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Infection caused by Orientia
  • Scrub typhus

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Scrub (mite-borne) typhus
  • Tsutsugamushi fever
  • Typhus fever due to Orientia Tsutsugamushi (scrub typhus)

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Disease, diseased
      • akamushi (scrub typhus)
    • Disease, diseased
      • island (scrub typhus)
    • Disease, diseased
      • Kedani (scrub typhus)
    • Disease, diseased
      • shimamushi (scrub typhus)
    • Disease, diseased
      • tsutsugamushi
    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • Japanese river
    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • kedani
    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • Sumatran mite
    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • tsutsugamushi
    • Infection, infected, infective(opportunistic)
      • typhus
        • mite-borne
    • Japanese
      • river fever
    • Kedani fever
    • Sumatran mite fever
    • Tsutsugamushi(disease) (fever)
    • Typhus(fever)
      • due to Rickettsia
        • tsutsugamushi
    • Typhus(fever)
      • mite-borne
    • Typhus(fever)
      • Orientia Tsutsugamushi (scrub typhus)
    • Typhus(fever)
      • scrub (China) (India) (Malaysia) (New Guinea)
    • Typhus(fever)
      • tropical (mite-borne)

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INF009
Parasitic, other specified and unspecified infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Scrub Typhus

    an acute infectious disease caused by orientia tsutsugamushi. it is limited to eastern and southeastern asia, india, northern australia, and the adjacent islands. characteristics include the formation of a primary cutaneous lesion at the site of the bite of an infected mite, fever lasting about two weeks, and a maculopapular rash.

  • Orientia tsutsugamushi

    a gram-negative, rod-shaped to coccoid bacterium. it is the etiologic agent of scrub typhus in humans and is transmitted by mites from rodent reservoirs.

Patient EducationClinical

Bacterial Infections

Bacteria are tiny organisms (living things) that have only one cell. Under a microscope, they look like balls, rods, or spirals. They can be found almost everywhere on Earth. There are lots of bacteria in and on your body. In fact, your body has about 10 times more bacteria cells than human cells.

The full article covers:

  • What are bacteria?
  • How do bacterial infections spread?
  • What are the treatments for bacterial infections?
  • Can bacterial infections be prevented?

Read the full article at MedlinePlus

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

Convert A75.3 to ICD-9-CMHistory

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

ICD-9-CM
081.2 Scrub typhus
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About A75.3Overview

Is A75.3 (Typhus fever) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report typhus fever due to Rickettsia tsutsugamushi on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does A75.3 group to?

When typhus fever due to Rickettsia tsutsugamushi is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 868, 869, with relative weights from 0.7297 to 2.0932 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of A75.3?

Under the General Equivalence Mappings, typhus fever due to Rickettsia tsutsugamushi converts to ICD-9-CM 081.2 (scrub typhus). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.