ICD-10 Code B87.9 – Myiasis, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B87.9 – Myiasis, unspecified
What it is
Myiasis is infestation of living tissue by fly larvae. Use this unspecified code when the record confirms myiasis but does not identify the site, type, or species.
Clinical signs
Findings may include visible larvae, draining skin lesions, pain, swelling, or a sensation of movement in the affected area. Clinical features vary; refer to documentation.
When to use this code
Use B87.9 when the provider documents myiasis without further detail. It also fits when the chart does not specify whether the infestation is cutaneous, wound-related, or another form. If the site or organism is documented, code the more specific option instead.
Do not use for
Do not use this code for simple insect bites, wounds without larval infestation, or parasitic infections that are not myiasis. Check documentation if the note only says “foreign body” or “infection.”
Coding tip
Review the assessment and procedure notes for the affected site, because unspecified myiasis should be reported only when no more specific detail is available.