A85.2
Arthropod-borne viral encephalitis, unspecified
Billable FY2026 2025-10-01 → 2026-09-30
This is the unspecified option. 3 more
specific codes sit alongside it. Worth
checking whether the documentation supports one of them.
Exclusions 18 never code together
A85code
Excludes1
- encephalitis due to cytomegalovirus (B25.8)B25.8
- encephalitis due to herpesvirus NEC (B10.0-)B10.0-
- encephalitis due to herpesvirus [herpes simplex] (B00.4)B00.4
- encephalitis due to measles virus (B05.0)B05.0
- encephalitis due to mumps virus (B26.2)B26.2
- encephalitis due to poliomyelitis virus (A80.-)A80.-
- encephalitis due to zoster (B02.0)B02.0
- lymphocytic choriomeningitis (A87.2)A87.2
- myalgic encephalomyelitis (G93.32)G93.32
A80-A89block
A00-B99chapter
Excludes1
- certain localized infections - see body system-related chapters
Excludes2
- carrier or suspected carrier of infectious disease (Z22.-)Z22.-
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)O98.-
- infectious and parasitic diseases specific to the perinatal period (P35-P39)P35-P39
- influenza and other acute respiratory infections (J00-J22)J00-J22
Excludes1 — never code together. The excluded condition and this one are mutually exclusive.
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 4
Index entries leading here 1
Alongside this code 3 same parent — A85
Medications 1
MED-RT files conditions by MeSH, which carves the world differently from ICD-10. These are name matches on this code's description, offered as candidates — not as an assertion that they are this code.
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.