Spotted fever [tick-borne rickettsioses] (A77) ICD-10-CM
The A77 code range covers spotted fever [tick-borne rickettsioses] with 11 ICD-10-CM diagnosis codes. 9 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Codes in the A77 Range 11 codes · 9 billable
- A77 Spotted fever [tick-borne rickettsioses]Non-billable
- A77.0 Spotted fever due to Rickettsia rickettsii
- A77.1 Spotted fever due to Rickettsia conorii
- A77.2 Spotted fever due to Rickettsia siberica
- A77.3 Spotted fever due to Rickettsia australis
- A77.4 EhrlichiosisNon-billable
- A77.40 Ehrlichiosis, unspecified
- A77.41 Ehrlichiosis chaffeensis [E. chaffeensis]
- A77.49 Other ehrlichiosis
- A77.8 Other spotted fevers
- A77.9 Spotted fever, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the A77 range.
Ehrlichiosis
A tick-borne disease characterized by FEVER; HEADACHE; myalgias; ANOREXIA; and occasionally RASH. It is caused by several bacterial species and can produce disease in DOGS; CATTLE; SHEEP; GOATS; HORSES; and humans. The primary species causing human disease are EHRLICHIA CHAFFEENSIS; ANAPLASMA PHAGOCYTOPHILUM; and Ehrlichia ewingii.
Spotted Fever Group Rickettsiosis
A group of arthropod-borne diseases caused by spotted fever bio-group members of RICKETTSIA. They are characterized by fever, headache, and petechial (spotted) rash.
About the A77 Code Range
Spotted fevers and ehrlichiosis appear together in this category of tick-borne rickettsioses.
The spotted fever codes distinguish the named Rickettsia species that cause them: A77.0 through A77.3. A77.4 branches into unspecified ehrlichiosis, ehrlichiosis chaffeensis and other ehrlichiosis. The remaining spotted fever codes distinguish other spotted fevers from unspecified spotted fever.
Questions About This Page
How many billable codes are in the A77 range?
Of the 11 codes in this range, 9 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the A77 range classify?
The range classifies spotted fever [tick-borne rickettsioses]. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
