ICD-10 Code B00.9 – Herpesviral infection, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B00.9 – Herpesviral infection, unspecified
What it is
B00.9 identifies a herpesvirus infection when the record does not specify the site or type. Use it for documented herpesviral disease without enough detail for a more specific code.
Clinical signs
Clinical features vary; refer to documentation. Common herpesvirus findings may include grouped vesicles, pain, itching, fever, or localized lesions, but the chart must support the diagnosis.
When to use this code
Use B00.9 when the provider documents herpesviral infection but does not name the anatomic site, organism, or clinical form. It also fits when the note confirms herpes infection and no more specific code is supported.
If the record later specifies oral, genital, ocular, or other herpes manifestations, code the documented condition instead. Check documentation carefully before selecting an unspecified code.
Do not use for
Do not use this code for a clearly documented herpes site or complication when a more specific ICD-10 code is available. Do not use it for non-herpetic viral infections.
Coding tip
Query the provider when “herpes” is documented without enough detail to support a more specific code.