Contact with and (suspected) exposure to communicable diseases (Z20) ICD-10-CM
The Z20 code range covers contact with and (suspected) exposure to communicable diseases with 23 ICD-10-CM diagnosis codes. 18 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- carrier of infectious disease Z22
- diagnosed current infectious or parasitic disease -see Alphabetic Index
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
- personal history of infectious and parasitic diseases Z86.1
Codes in the Z20 Range 23 codes · 18 billable
- Z20 Contact with and (suspected) exposure to communicable diseasesNon-billable
- Z20.0 Contact with and (suspected) exposure to intestinal infectious diseasesNon-billable
- Z20.01 Contact with and (suspected) exposure to intestinal infectious diseases due to Escherichia coli (E. coli)
- Z20.09 Contact with and (suspected) exposure to other intestinal infectious diseases
- Z20.1 Contact with and (suspected) exposure to tuberculosis
- Z20.2 Contact with and (suspected) exposure to infections with a predominantly sexual mode of transmission
- Z20.3 Contact with and (suspected) exposure to rabies
- Z20.4 Contact with and (suspected) exposure to rubella
- Z20.5 Contact with and (suspected) exposure to viral hepatitis
- Z20.6 Contact with and (suspected) exposure to human immunodeficiency virus [HIV]
- Z20.7 Contact with and (suspected) exposure to pediculosis, acariasis and other infestations
- Z20.8 Contact with and (suspected) exposure to other communicable diseasesNon-billable
- Z20.81 Contact with and (suspected) exposure to other bacterial communicable diseasesNon-billable
- Z20.810 Contact with and (suspected) exposure to anthrax
- Z20.811 Contact with and (suspected) exposure to meningococcus
- Z20.818 Contact with and (suspected) exposure to other bacterial communicable diseases
- Z20.82 Contact with and (suspected) exposure to other viral communicable diseasesNon-billable
- Z20.820 Contact with and (suspected) exposure to varicella
- Z20.821 Contact with and (suspected) exposure to Zika virus
- Z20.822 Contact with and (suspected) exposure to COVID-19
- Z20.828 Contact with and (suspected) exposure to other viral communicable diseases
- Z20.89 Contact with and (suspected) exposure to other communicable diseases
- Z20.9 Contact with and (suspected) exposure to unspecified communicable disease
About the Z20 Code Range
The Z20 ICD-10 codes describe medical encounters involving contact with or suspected exposure to various communicable diseases. These codes help document potential exposure risks rather than confirmed infections.
Each code under Z20 targets specific categories of communicable diseases. For example, Z20.01 is used when there is suspected exposure to intestinal infections caused by Escherichia coli (E. coli), while Z20.1 covers exposure to tuberculosis or Mycobacterium tuberculosis. Codes like Z20.6 document contact with HIV, and Z20.822 captures suspected or occupational exposure to COVID-19 or SARS-CoV-2. There are also codes addressing exposure to sexually transmitted infections (Z20.2), rabies (Z20.3), rubella (Z20.4), and viral hepatitis (Z20.5). The Z20.8 series includes other bacterial and viral communicable diseases, such as anthrax (Z20.810) and meningococcus (Z20.811), or varicella (Z20.820) and Zika virus (Z20.821). When the disease is unspecified or does not fit these categories, Z20.9 is used. These codes assist healthcare professionals and coders in accurately recording suspected exposure situations to guide testing and preventive care.
Questions About This Page
How many billable codes are in the Z20 range?
Of the 23 codes in this range, 18 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the Z20 range classify?
The range classifies contact with and (suspected) exposure to communicable diseases. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
