A78 — Q fever
Is A78 billable?
Yes — A78 is billable for FY2027. A78 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. A78 may be submitted for encounters from October 1, 2026 through September 30, 2027.
A78 at a glance
| Code | A78 |
|---|---|
| Description | Q fever |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does A78 group to?
A78 sits in MDC 18 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 867Other Infectious and Parasitic Diseases Diagnoses with MCCmedical
- 868Other Infectious and Parasitic Diseases Diagnoses with CCmedical
- 869Other Infectious and Parasitic Diseases Diagnoses without CC/MCCmedical
As a secondary diagnosis, A78 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is A78 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to A78. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Balkan grippe
- Q fever
- Quadrilateral fever
- Australian › Q fever
- Endocarditis › Coxiella burnetii (chronic) (marantic) (nonbacterial) (thrombotic) (valvular)
- Endocarditis › Q fever (chronic) (marantic) (nonbacterial) (thrombotic) (valvular)
- Fever › Australian Q (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › Nine-Mile (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › Q (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › quadrilateral (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Grippe, grippal › Balkan
- Infection, infected, infective › Coxiella burnetii (opportunistic)
Inclusion terms
Alternative wording in documentation that is classified to A78.
- Infection due to Coxiella burnetii
- Nine Mile fever
- Quadrilateral fever
Use additional code — inherited from Chapter 1
Report an additional code alongside A78 to fully describe the condition. A78 is sequenced first.
- code to identify resistance to antimicrobial drugs (Z16.-)
Excludes2 — not included here — inherited from Chapter 1
The conditions below are not part of A78, but a patient may have both at the same time. When documentation supports it, A78 and the excluded code may both be reported.
- 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)
How long has A78 existed?
A78 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.