B03 Smallpox

Billable

Block: Viral infections characterized by skin and mucous membrane lesions (B00-B09)

Notes

  • In 1980 the 33rd World Health Assembly declared that smallpox had been eradicated.
  • The classification is maintained for surveillance purposes.
This category is a complete, billable diagnosis code.

No additional specificity is required — submit B03 directly on claims and documentation without a subcode extension.

Last reviewed: September 2026