DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

B01 Varicella [chickenpox]

  • Header · not billable

B01 is not billable. The category heads 7 billable codes in FY2027, grouped under 5 subdivisions.

Index → code

  • Varicella → B01.9
  • Encephalomyelitispostvaricella → B01.11
  • Encephalomyelitispostchickenpox → B01.11

Where it sits

  1. Chapter 1 Certain infectious and parasitic diseases (A00-B99)
  2. B00-B09 Viral infections characterized by skin and mucous membrane lesions (B00-B09)
  3. B01 Varicella [chickenpox]
Billable codes
7
Subdivisions
5
CC / MCC codes
4 / 3
HCC V28 codes
1
New FY2027
0
Index entries
20

Codes in B01

  1. B01.0
    Varicella meningitis
    BillableCC
  2. B01.1
    Varicella encephalitis, myelitis and encephalomyelitis
    Header
    Inclusion terms 1

    Inclusion terms

    • Postchickenpox encephalitis, myelitis and encephalomyelitis
  3. B01.11
    Varicella encephalitis and encephalomyelitis
    BillableMCC
    Inclusion terms 1

    Inclusion terms

    • Postchickenpox encephalitis and encephalomyelitis
  4. B01.12
    Varicella myelitis
    BillableMCC182
    Inclusion terms 1

    Inclusion terms

    • Postchickenpox myelitis
  5. B01.2
    Varicella pneumonia
    BillableMCC
  6. B01.8
    Varicella with other complications
    Header
  7. B01.81
    Varicella keratitis
    BillableCC
  8. B01.89
    Other varicella complications
    BillableCC
  9. B01.9
    Varicella without complication
    BillableCC
    Inclusion terms 1

    Inclusion terms

    • Varicella NOS

CC/MCC: as a secondary diagnosis, unless the principal diagnosis is on the code’s PDX exclusion list (MS-DRG v44 Appendix C; list on the code card).

Sources of each column.

Instructions

Notes that also apply

Chapter 1 instructions (Includes 1, Excludes2 5, Use additional code 1): printed on the chapter 1 page.

Index entries

  • Varicella → B01.9
  • Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute)postchickenpox → B01.11
  • Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute)postvaricella → B01.11
  • Encephalomyelitispostchickenpox → B01.11
  • Encephalomyelitispostvaricella → B01.11
  • Myelitis (acute) (ascending) (childhood) (chronic) (descending) (diffuse) (disseminated) (idiopathic) (pressure) (progressive) (spinal cord) (subacute)postchickenpox → B01.12
  • Myelitis (acute) (ascending) (childhood) (chronic) (descending) (diffuse) (disseminated) (idiopathic) (pressure) (progressive) (spinal cord) (subacute)varicella → B01.12
  • Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved)varicella → B01.2
  • Infection, infected, infective (opportunistic)varicella → B01.9
  • Meningitis (basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic)in (due to)chickenpox → B01.0
  • Meningitis (basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic)in (due to)varicella → B01.0
  • Varicellawithmeningitis → B01.0
  • Varicellawithencephalitis → B01.11
  • Varicellawithencephalomyelitis → B01.11
  • Varicellawithmyelitis → B01.12
  • Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved)in (due to)chickenpox → B01.2
  • Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved)in (due to)varicella → B01.2
  • Varicellawithpneumonia → B01.2
  • Keratitis (nodular) (nonulcerative) (simple) (zonular)disciform (is) (herpes simplex)varicella → B01.81
  • Varicellawithcomplications NEC → B01.89

NCHS Alphabetic Index. Index first, then the Tabular List.

Hierarchy