Certain infectious and parasitic diseases (A00–B99)

Browse all the diagnosis codes used for certain infectious and parasitic diseases (a00–b99). For easy navigation, the diagnosis codes are sorted in alphabetical order and grouped by sections. Each section is clearly marked with its description, and the corresponding three-digit code range. This format makes it simple to browse diagnosis codes in this chapter or section and find what you're looking for. We've also added green checkmark icons to label billable codes, and red warning icons for non-billable ones. This makes it easy to identify which codes can be billed.
  • Certain infectious and parasitic diseases (A00–B99)

    Includes: diseases generally recognized as communicable or transmissible Use additional code to identify resistance to antimicrobial drugs (Z16.-)
    Excludes1: certain localized infections - see body system-related chapters
    Excludes2: carrier or suspected carrier of infectious disease (Z22.-), infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-), infectious and parasitic diseases specific to the perinatal period (P35-P39), influenza and other acute respiratory infections (J00-J22).

    • Intestinal infectious diseases (A00-A09)

      • Cholera (A00)
      • Typhoid and paratyphoid fevers (A01)
      • Other salmonella infections (A02)
      • Shigellosis (A03)
      • Other bacterial intestinal infections (A04)
      • Other bacterial foodborne intoxications, not elsewhere classified (A05)
      • Amebiasis (A06)
      • Other protozoal intestinal diseases (A07)
      • Viral and other specified intestinal infections (A08)
      • Infectious gastroenteritis and colitis, unspecified (A09)
    • Tuberculosis (A15-A19)

      • Respiratory tuberculosis (A15)
      • Tuberculosis of nervous system (A17)
      • Tuberculosis of other organs (A18)
      • Miliary tuberculosis (A19)
    • Certain zoonotic bacterial diseases (A20-A28)

      • Plague (A20)
      • Tularemia (A21)
      • Anthrax (A22)
      • Brucellosis (A23)
      • Glanders and melioidosis (A24)
      • Rat-bite fevers (A25)
      • Erysipeloid (A26)
      • Leptospirosis (A27)
      • Other zoonotic bacterial diseases, not elsewhere classified (A28)
    • Other bacterial diseases (A30-A49)

      • Leprosy [Hansen's disease] (A30)
      • Infection due to other mycobacteria (A31)
      • Listeriosis (A32)
      • Tetanus neonatorum (A33)
      • Obstetrical tetanus (A34)
      • Other tetanus (A35)
      • Diphtheria (A36)
      • Whooping cough (A37)
      • Scarlet fever (A38)
      • Meningococcal infection (A39)
      • Streptococcal sepsis (A40)
      • Other sepsis (A41)
      • Actinomycosis (A42)
      • Nocardiosis (A43)
      • Bartonellosis (A44)
      • Erysipelas (A46)
      • Other bacterial diseases, not elsewhere classified (A48)
      • Bacterial infection of unspecified site (A49)
    • Infections with a predominantly sexual mode of transmission (A50-A64)

      • Congenital syphilis (A50)
      • Early syphilis (A51)
      • Late syphilis (A52)
      • Other and unspecified syphilis (A53)
      • Gonococcal infection (A54)
      • Chlamydial lymphogranuloma (venereum) (A55)
      • Other sexually transmitted chlamydial diseases (A56)
      • Chancroid (A57)
      • Granuloma inguinale (A58)
      • Trichomoniasis (A59)
      • Anogenital herpesviral [herpes simplex] infections (A60)
      • Other predominantly sexually transmitted diseases, not elsewhere classified (A63)
      • Unspecified sexually transmitted disease (A64)
    • Other spirochetal diseases (A65-A69)

      • Nonvenereal syphilis (A65)
      • Yaws (A66)
      • Pinta [carate] (A67)
      • Relapsing fevers (A68)
      • Other spirochetal infections (A69)
    • Other diseases caused by chlamydiae (A70-A74)

      • Chlamydia psittaci infections (A70)
      • Trachoma (A71)
      • Other diseases caused by chlamydiae (A74)
    • Rickettsioses (A75-A79)

      • Typhus fever (A75)
      • Spotted fever [tick-borne rickettsioses] (A77)
      • Q fever (A78)
      • Other rickettsioses (A79)
    • Viral and prion infections of the central nervous system (A80-A89)

      • Acute poliomyelitis (A80)
      • Atypical virus infections of central nervous system (A81)
      • Rabies (A82)
      • Mosquito-borne viral encephalitis (A83)
      • Tick-borne viral encephalitis (A84)
      • Other viral encephalitis, not elsewhere classified (A85)
      • Unspecified viral encephalitis (A86)
      • Viral meningitis (A87)
      • Other viral infections of central nervous system, not elsewhere classified (A88)
      • Unspecified viral infection of central nervous system (A89)
    • Arthropod-borne viral fevers and viral hemorrhagic fevers (A90-A99)

      • Dengue fever [classical dengue] (A90)
      • Dengue hemorrhagic fever (A91)
      • Other mosquito-borne viral fevers (A92)
      • Other arthropod-borne viral fevers, not elsewhere classified (A93)
      • Unspecified arthropod-borne viral fever (A94)
      • Yellow fever (A95)
      • Arenaviral hemorrhagic fever (A96)
      • Other viral hemorrhagic fevers, not elsewhere classified (A98)
      • Unspecified viral hemorrhagic fever (A99)
    • Viral infections characterized by skin and mucous membrane lesions (B00-B09)

      • Herpesviral [herpes simplex] infections (B00)
      • Varicella [chickenpox] (B01)
      • Zoster [herpes zoster] (B02)
      • Smallpox (B03)
      • Monkeypox (B04)
      • Measles (B05)
      • Rubella [German measles] (B06)
      • Viral warts (B07)
      • Other viral infections characterized by skin and mucous membrane lesions, not elsewhere classified (B08)
      • Unspecified viral infection characterized by skin and mucous membrane lesions (B09)
    • Other human herpesviruses (B10)

      • Other human herpesviruses (B10)
    • Viral hepatitis (B15-B19)

      • Acute hepatitis A (B15)
      • Acute hepatitis B (B16)
      • Other acute viral hepatitis (B17)
      • Chronic viral hepatitis (B18)
      • Unspecified viral hepatitis (B19)
    • Human immunodeficiency virus [HIV] disease (B20)

      • Human immunodeficiency virus [HIV] disease (B20)
    • Other viral diseases (B25-B34)

      • Cytomegaloviral disease (B25)
      • Mumps (B26)
      • Infectious mononucleosis (B27)
      • Viral conjunctivitis (B30)
      • Other viral diseases, not elsewhere classified (B33)
      • Viral infection of unspecified site (B34)
    • Mycoses (B35-B49)

      • Dermatophytosis (B35)
      • Other superficial mycoses (B36)
      • Candidiasis (B37)
      • Coccidioidomycosis (B38)
      • Histoplasmosis (B39)
      • Blastomycosis (B40)
      • Paracoccidioidomycosis (B41)
      • Sporotrichosis (B42)
      • Chromomycosis and pheomycotic abscess (B43)
      • Aspergillosis (B44)
      • Cryptococcosis (B45)
      • Zygomycosis (B46)
      • Mycetoma (B47)
      • Other mycoses, not elsewhere classified (B48)
      • Unspecified mycosis (B49)
    • Protozoal diseases (B50-B64)

      • Plasmodium falciparum malaria (B50)
      • Plasmodium vivax malaria (B51)
      • Plasmodium malariae malaria (B52)
      • Other specified malaria (B53)
      • Unspecified malaria (B54)
      • Leishmaniasis (B55)
      • African trypanosomiasis (B56)
      • Chagas' disease (B57)
      • Toxoplasmosis (B58)
      • Pneumocystosis (B59)
      • Other protozoal diseases, not elsewhere classified (B60)
      • Unspecified protozoal disease (B64)
    • Helminthiases (B65-B83)

      • Schistosomiasis [bilharziasis] (B65)
      • Other fluke infections (B66)
      • Echinococcosis (B67)
      • Taeniasis (B68)
      • Cysticercosis (B69)
      • Diphyllobothriasis and sparganosis (B70)
      • Other cestode infections (B71)
      • Dracunculiasis (B72)
      • Onchocerciasis (B73)
      • Filariasis (B74)
      • Trichinellosis (B75)
      • Hookworm diseases (B76)
      • Ascariasis (B77)
      • Strongyloidiasis (B78)
      • Trichuriasis (B79)
      • Enterobiasis (B80)
      • Other intestinal helminthiases, not elsewhere classified (B81)
      • Unspecified intestinal parasitism (B82)
      • Other helminthiases (B83)
    • Pediculosis, acariasis and other infestations (B85-B89)

      • Pediculosis and phthiriasis (B85)
      • Scabies (B86)
      • Myiasis (B87)
      • Other infestations (B88)
      • Unspecified parasitic disease (B89)
    • Sequelae of infectious and parasitic diseases (B90-B94)

      • Sequelae of tuberculosis (B90)
      • Sequelae of poliomyelitis (B91)
      • Sequelae of leprosy (B92)
      • Sequelae of other and unspecified infectious and parasitic diseases (B94)
    • Bacterial and viral infectious agents (B95-B97)

      • Streptococcus, Staphylococcus, and Enterococcus as the cause of diseases classified elsewhere (B95)
      • Other bacterial agents as the cause of diseases classified elsewhere (B96)
      • Viral agents as the cause of diseases classified elsewhere (B97)
    • Other infectious diseases (B99)

      • Other and unspecified infectious diseases (B99)