2026 ICD-10-CM Diagnosis Code A20Plague

ICD-10-CM Codes›A00–B99›A20-A28›A20

ICD-10-CM A20
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A20 is a non-billable ICD-10-CM category code for plague, so it cannot be submitted on claims. Use a more specific code from this category instead, such as A20.0, A20.1, A20.2, and A20.3.

Code Identity

ICD-10-CM Code
A20
Billable Status
No — Non-Billable Category
Code Describes
Plague
Chapter
A20-A28
Certain zoonotic bacterial diseases

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA20-A28Certain zoonotic bacterial diseases
CategoryA20Plague
This CodeA20Plague

Specific Coding for PlagueOverview

Non-specific codes like A20 require more characters. Use one of these billable codes instead:

  • Use A20.0 for Bubonic plague

  • Use A20.1 for Cellulocutaneous plague

  • Use A20.2 for Pneumonic plague

  • Use A20.3 for Plague meningitis

  • Use A20.7 for Septicemic plague

  • Use A20.8 for Other forms of plague

  • Use A20.9 for Plague, unspecified

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Includes

  • infection due to Yersinia pestis

Clinical InformationClinical

  • African Horse Sickness

    an insect-borne reovirus infection of horses, mules and donkeys in africa and the middle east; characterized by pulmonary edema, cardiac involvement, and edema of the head and neck.

  • Feline Panleukopenia

    a highly contagious dna virus infection of the cat family, characterized by fever, enteritis and bone marrow changes. it is also called feline ataxia, feline agranulocytosis, feline infectious enteritis, cat fever, cat plague, and show fever. it is caused by feline panleukopenia virus or the closely related mink enteritis virus or canine parvovirus.

  • Influenza A virus

    the type species of the genus alphainfluenzavirus that causes influenza and other diseases in humans and animals. antigenic variation occurs frequently between strains, allowing classification into subtypes and variants. transmission is usually by aerosol (human and most non-aquatic hosts) or waterborne (ducks). infected birds shed the virus in their saliva, nasal secretions, and feces.

  • Influenza in Birds

    infection of domestic and wild fowl and other birds with influenza a virus. avian influenza usually does not sicken birds, but can be highly pathogenic and fatal in domestic poultry.

  • Plague

    an acute infectious disease caused by yersinia pestis that affects humans, wild rodents, and their ectoparasites. this condition persists due to its firm entrenchment in sylvatic rodent-flea ecosystems throughout the world. bubonic plague is the most common form.

  • Plague Vaccine

    a suspension of killed yersinia pestis used for immunizing people in enzootic plague areas.

  • Rinderpest

    a viral disease of cloven-hoofed animals caused by morbillivirus. it may be acute, subacute, or chronic with the major lesions characterized by inflammation and ulceration of the entire digestive tract. the disease was declared successfully eradicated worldwide in 2010.

  • Alphainfluenzavirus

    a genus in the family orthomyxoviridae causing influenza and other diseases in humans and animals. it contains many strains as well as antigenic subtypes of the integral membrane proteins hemagglutinin (viral hemagglutinins) and neuraminidase. the type species is influenza a virus.

  • Yersinia pestis

    the etiologic agent of plague in man, rats, ground squirrels, and other rodents.

  • Morbillivirus

    a genus of the family paramyxoviridae (subfamily paramyxovirinae) where the virions of most members have hemagglutinin but not neuraminidase activity. all members produce both cytoplasmic and intranuclear inclusion bodies. measles virus is the type species.

  • Plague

    a gram-negative bacterial infection caused by yersinia pestis. it is usually transmitted to humans from bites of infected rodent fleas. it is manifested as a bubonic, septicemic, or pneumonic plague. in bubonic plague, the lymph nodes adjacent to the site of the skin bite are infected and enlarged. in septicemic plague, the infection spreads directly through the bloodstream. in pneumonic plague, the infection spreads to the lungs either following bubonic plague, or by inhalation of infective droplets. if untreated, it may lead to death.

Patient EducationClinical

Plague

Plague is an infection caused by the bacterium Yersinia pestis. The bacteria are found mainly in rats and in the fleas that feed on them. People and other animals can get plague from rat or flea bites. In the past, plague destroyed entire civilizations. Today plague is uncommon, due to better living conditions and antibiotics.

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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About A20Overview

Is A20 (Plague) a billable code?

No. This is a category header that groups the codes for plague, and headers cannot be submitted on claims. Claims for plague need a more specific code from this category, such as A20.0, A20.1, and A20.2.