Q fever (A78) ICD-10-CM
The A78 code range covers q fever with 1 ICD-10-CM diagnosis codes. 1 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
- Infection due to Coxiella burnetii
- Nine Mile fever
- Quadrilateral fever
Codes in the A78 Range 1 codes · 1 billable
- A78 Q fever
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the A78 range.
Q Fever
An acute infectious disease caused by COXIELLA BURNETII. It is characterized by a sudden onset of FEVER; HEADACHE; malaise; and weakness. In humans, it is commonly contracted by inhalation of infected dusts derived from infected domestic animals (ANIMALS, DOMESTIC).
About the A78 Code Range
ICD-10 code A78 is used specifically to identify Q fever, a bacterial infection caused by the bacterium Coxiella burnetii. This code applies whenever a diagnosis relates to Q fever or its various complications.
Q fever can present under several names and conditions, including acute or chronic Q fever, and may affect different tissues such as the heart (e.g., Q fever myocarditis, pericarditis, endocarditis), lungs (pneumonia in Q fever), liver (bacterial hepatitis, Q fever hepatitis), or nervous system (e.g., meningitis, encephalitis, encephalomyelitis). It can also cause bone infections like osteomyelitis or inflammation of the spinal cord (myelitis). Including these diverse synonyms helps medical coders match clinical terms to the correct ICD-10 code for Q fever, ensuring accurate diagnosis coding for this specific bacterial infection. The ICD-10 code for Q fever (A78) thus covers a spectrum of manifestations caused by Coxiella burnetii, distinguishing these infections from other bacterial illnesses.
Questions About This Page
How many billable codes are in the A78 range?
Of the 1 codes in this range, 1 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the A78 range classify?
The range classifies q fever. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
