2027 ICD-10-CM Diagnosis Code Z20Contact with and (suspected) exposure to communicable diseases

ICD-10-CM Codes›Z00–Z99›Z20-Z29›suspected

ICD-10-CM Z20
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Z20 is a non-billable ICD-10-CM category code for contact with and (suspected) exposure to communicable diseases, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Z20.01, Z20.09, Z20.1, and Z20.2.

Code Identity

ICD-10-CM Code
Z20
Billable Status
No — Non-Billable Category
Code Describes
Contact with and (suspected) exposure to communicable diseases
Short Description
Contact w and (suspected) exposure to communicable diseases
Chapter
Z20-Z29
Persons with potential health hazards related to communicable diseases

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ20-Z29Persons with potential health hazards related to communicable diseases
CategorysuspectedContact with and exposure to communicable diseases (Z20)
This CodeZ20Contact with and (suspected) exposure to communicable diseases

Specific Coding for Contact w and (suspected) exposure to communicable diseasesOverview

Non-specific codes like Z20 require more characters. Use one of these billable codes instead:

  • Z20.0 for Contact with and (suspected) exposure to intestinal infectious diseases

  • Use Z20.01 for Contact with and (suspected) exposure to intestinal infectious diseases due to Escherichia coli (E. coli)

  • Use Z20.09 for Contact with and (suspected) exposure to other intestinal infectious diseases

  • Use Z20.1 for Contact with and (suspected) exposure to tuberculosis

  • Use Z20.2 for Contact with and (suspected) exposure to infections with a predominantly sexual mode of transmission

  • Use Z20.3 for Contact with and (suspected) exposure to rabies

  • Use Z20.4 for Contact with and (suspected) exposure to rubella

  • Use Z20.5 for Contact with and (suspected) exposure to viral hepatitis

  • Use Z20.6 for Contact with and (suspected) exposure to human immunodeficiency virus [HIV]

  • Use Z20.7 for Contact with and (suspected) exposure to pediculosis, acariasis and other infestations

  • Z20.8 for Contact with and (suspected) exposure to other communicable diseases

  • Z20.81 for Contact with and (suspected) exposure to other bacterial communicable diseases

  • Z20.82 for Contact with and (suspected) exposure to other viral communicable diseases

  • Use Z20.89 for Contact with and (suspected) exposure to other communicable diseases

  • Use Z20.9 for Contact with and (suspected) exposure to unspecified communicable disease

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Z20: its own notes plus those printed at Chapter 21. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

  • carrier of infectious disease (Z22.-)
  • diagnosed current infectious or parasitic disease -see Alphabetic Index

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

  • personal history of infectious and parasitic diseases (Z86.1-)

Notes

General instructions on how these codes are used.

From Chapter 21 (Z00-Z99) Factors influencing health status and contact with health services applies to 1,425 codes
  • Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
  • (a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
  • (b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Z20, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming Z20: its condition is not part of those codes, and both may be reported when the patient has both.

  • Z77 Other contact with and (suspected) exposures hazardous to health
    contact with and (suspected) exposure to communicable diseases (Z20.-)
  • Z83 Family history of other specific disorders
    contact with and (suspected) exposure to communicable disease in the family (Z20.-)

Patient EducationClinical

Infectious Diseases

Germs, or microbes, are found everywhere - in the air, soil, and water. There are also germs on your skin and in your body. Many of them are harmless, and some can even be helpful. But some of them can make you sick. Infectious diseases are diseases that are caused by germs.

The full article covers:

  • What are infectious diseases?
  • What are the different types of germs that cause infectious diseases?
  • How can you get infectious diseases?
  • What are the symptoms of infectious diseases?
  • What are the treatments for infectious diseases?
  • Can infectious diseases be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Z20Overview

What is the ICD-10 code for contact with and (suspected) exposure to communicable diseases?

Z20 is the ICD-10-CM category for contact with and (suspected) exposure to communicable diseases, but it is a non-billable header: claims need a more specific code from this category, listed on this page.

Is Z20 a billable code?

No. This is a category header that groups the codes for contact with and (suspected) exposure to communicable diseases, and headers cannot be submitted on claims. Claims for contact with and (suspected) exposure to communicable diseases need a more specific code from this category, such as Z20.01, Z20.09, and Z20.1.

Can Z20 be reported with a code from Z22?

Not as a rule. The Excludes1 note on Z20 lists "carrier of infectious disease (Z22.-)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).