ICD-10-CM 2027 diagnosis code

B66Other fluke infections

Not billable — use a more specific code

B66 is a header code, so it can't be reported by itself. Choose one of the 8 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About B66

B66 is the ICD-10-CM diagnosis code for other fluke infections. It belongs to block B65-B83 (helminthiases) and chapter 1 (certain infectious and parasitic diseases). It is a header code, so it can't be reported by itself; one of its 8 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: B66.0 (Opisthorchiasis), B66.1 (Clonorchiasis), B66.2 (Dicroceliasis), B66.3 (Fascioliasis), B66.4 (Paragonimiasis), B66.5 (Fasciolopsiasis), B66.8 (infections) and B66.9 (unspecified).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under B66

Notes that apply from higher levels

Instructions written at a parent level also apply to B66.

Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.

Code history

2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about B66

Is B66 billable?: No. B66 is a header code. Report one of its more specific subcodes instead.