ICD-10 Code B94.9 – Sequelae of unspecified infectious and parasitic disease (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B94.9 – Sequelae of unspecified infectious and parasitic disease
What it is
This code describes late effects that remain after an unspecified infectious or parasitic disease has ended. Use it when the current problem is a residual condition, not an active infection.
Clinical signs
Clinical features vary; refer to documentation. You may see persistent weakness, organ damage, scarring, or other lasting changes attributed to a prior infection or parasite exposure.
When to use this code
Use B94.9 when the record clearly links a current residual condition to a past infectious or parasitic illness, but the original disease is not specified. It is appropriate for sequelae documented as post-infectious or post-parasitic effects. If the active infection is still being treated, check documentation and code the current illness instead.
Do not use for
Do not use this code for an active infection, an unspecified infectious disease without sequelae, or a residual condition with a more specific postinfectious code. Check documentation.
Coding tip
Sequence the residual manifestation first, then add B94.9 only when the provider documents a sequela relationship.