ICD-10 Code for Ehrlichiosis

The ICD-10-CM code for ehrlichiosis is A77.40 — Ehrlichiosis, unspecified. This is the code the Alphabetic Index gives for ehrlichiosis with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).

BillableUnspecified

A77.40 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.

Which ehrlichiosis code should you use?

The Alphabetic Index lists 4 codes under Ehrlichiosis. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.

Ehrlichiosis due to

E. chaffeensisA77.41Ehrlichiosis chaffeensis [E. chaffeensis]
E. ewingiiA77.49Other ehrlichiosis
E. muris euclairensisA77.49Other ehrlichiosis
E. sennetsuA79.81Rickettsiosis due to Ehrlichia sennetsu
specified organism NECA77.49Other ehrlichiosis

Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources