ICD-10 Code B77.9 – Ascariasis, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B77.9 – Ascariasis, unspecified
What it is
B77.9 identifies ascariasis when the record does not specify the species or further detail. Use it for infection with Ascaris worms when documentation is limited or nonspecific.
Clinical signs
Clinical features vary; refer to documentation. Commonly noted findings may include abdominal discomfort, nausea, cough, or evidence of intestinal worm infection.
When to use this code
Use B77.9 when the clinician documents ascariasis but does not identify a more specific form or complication. It also fits when the note confirms Ascaris infection without added detail. If the record names a different helminth or complication, code that diagnosis instead.
Do not use for
Do not use this code for other parasitic infections, such as schistosomiasis or hookworm disease. Check documentation if the chart describes a specific complication, species, or mixed helminth infection.
Coding tip
Code the most specific documented parasite diagnosis, and default to B77.9 only when the provider leaves ascariasis unspecified.