P35.9

Congenital viral disease, unspecified

FY2027Chapter 16: Certain conditions originating in the perinatal period/P35–P39 Infections specific to the perinatal period

BillableComplete code, valid to report
Care settingsHospital MCC

P35.9 (also written P359) is a billable ICD-10-CM diagnosis code for congenital viral disease, unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 7 codes in category P35 (Congenital viral diseases). The Alphabetic Index lists it under 3 entries. Its coding notes include 15 Excludes2 entries.

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

Chapter 16 codes are never used on the maternal record, and chapter 15 codes are never used on the newborn record. Chapter 16 codes can be used for life if the condition persists.

Guidelines I.C.16.a.1Perinatal codes and the maternal recordRead the official text

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (15 notes)
Inherited from P35–P39 Infections specific to the perinatal period
  • asymptomatic human immunodeficiency virus [HIV] infection status (Z21)
  • congenital gonococcal infection (A54.-)
  • congenital pneumonia (P23.-)
  • congenital syphilis (A50.-)
  • human immunodeficiency virus [HIV] disease (B20)
  • infant botulism (A48.51)
  • infectious diseases not specific to the perinatal period (A00-B99, J09, J10.-)
  • intestinal infectious disease (A00-A09)
  • laboratory evidence of human immunodeficiency virus [HIV] (R75)
  • tetanus neonatorum (A33)
Inherited from Chapter 16 Certain conditions originating in the perinatal period
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • tetanus neonatorum (A33)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Hospital MCC

Counts as a major complication or comorbidity (MCC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 190 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

Includes

Further defines or gives examples of the content of the category.

Inherited from P35 Congenital viral diseases
  • infections acquired in utero or during birth
Also from chapter/block level (1 note)
Inherited from Chapter 16 Certain conditions originating in the perinatal period
  • conditions that have their origin in the fetal or perinatal period (before birth through the first 28 days after birth) even if morbidity occurs later

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 16 Certain conditions originating in the perinatal period
  • Codes from this chapter are for use on newborn records only, never on maternal records

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 3 entries