Chapter 1: Certain Infectious or Parasitic Diseases
ICD-11 codes 1A00-1H0Z
Covers infections caused by bacteria, viruses, fungi, and parasites, including gastroenteritis, tuberculosis, HIV, sexually transmitted infections, and viral hepatitis. ICD-11 reorganizes infectious diseases with updated classification of antimicrobial resistance and emerging infections.
1A00-1A0Z
Bacterial intestinal infections
1A00Cholera
1A01Intestinal infection due to other Vibrio
1A02Intestinal infections due to Shigella
1A03Intestinal infections due to Escherichia coli
1A04Intestinal infections due to Clostridioides difficile
1A05Intestinal infections due to Yersinia enterocolitica
1A06Gastroenteritis due to Campylobacter
1A07Typhoid fever
1A08Paratyphoid fever
1A09Infections due to other Salmonella
1A0YOther specified bacterial intestinal infections
1A0ZBacterial intestinal infections, unspecified
1A00-1A40
Gastroenteritis or colitis of infectious origin
1A10-1A1Z
Bacterial foodborne intoxications
1A20-1A2Z
Viral intestinal infections
1A30-1A3Z
Protozoal intestinal infections
1A60-1A6Z
Syphilis
1A60-1A9Z
Predominantly sexually transmitted infections
1A70-1A7Z
Gonococcal infection
1A80-1A8Z
Sexually transmissible infections due to chlamydia
1B10-1B1Z
Tuberculosis
1B10-1B2Z
Mycobacterial diseases
1B40-1B42
Acute rheumatic fever
1B40-1B5Z
Certain staphylococcal or streptococcal diseases
1B70-1B7Z
Pyogenic bacterial infections of the skin or subcutaneous tissues
1B70Bacterial cellulitis, erysipelas or lymphangitis
1B71Necrotising fasciitis
1B72Impetigo
1B73Ecthyma
1B74Superficial bacterial folliculitis
1B75Deep bacterial folliculitis or pyogenic abscess of the skin
1B7YOther specified pyogenic bacterial infection of skin or subcutaneous tissue
1B7ZPyogenic bacterial infection of skin or subcutaneous tissue, unspecified
1B90-1B9Z
Certain zoonotic bacterial diseases
1C10-1C4Z
Other bacterial diseases
1C10Actinomycosis
1C11Bartonellosis
1C12Whooping cough
1C13Tetanus
1C14Obstetrical tetanus
1C15Tetanus neonatorum
1C16Gas gangrene
1C17Diphtheria
1C18Brazilian purpuric fever
1C19Legionellosis
1C1AListeriosis
1C1BNocardiosis
1C1CMeningococcal disease
1C1DYaws
1C1EPinta
1C1FEndemic non-venereal syphilis
1C1GLyme borreliosis
1C1HNecrotising ulcerative gingivitis
1C1JRelapsing fever
1C40Campylobacteriosis
1C41Bacterial infection of unspecified site
1C42Melioidosis
1C43Actinomycetoma
1C44Non-pyogenic bacterial infections of the skin
1C45Toxic shock syndrome
1C4YOther specified bacterial diseases
1C4ZUnspecified bacterial disease
1C20-1C2Z
Other diseases due to chlamydiae
1C30-1C3Z
Rickettsioses
1C60-1C62
Human immunodeficiency virus disease
1C80-1C8Z
Viral infections of the central nervous system
1C80Viral encephalitis, not elsewhere classified
1C81Acute poliomyelitis
1C82Rabies
1C83Western equine encephalitis
1C84Eastern equine encephalitis
1C85Japanese encephalitis
1C86St Louis encephalitis
1C87Rocio viral encephalitis
1C88Murray Valley encephalitis
1C8BCalifornia encephalitis
1C8CVenezuelan equine encephalitis
1C8DLa Crosse encephalitis
1C8EViral meningitis, not elsewhere classified
1C8FLymphocytic choriomeningitis
1C8GTick-borne encephalitis
1C8HViral myelitis, not elsewhere classified
1C8YOther specified viral infections of the central nervous system
1C8ZViral infections of the central nervous system, unspecified
1D00-1D0Z
Non-viral and unspecified infections of the central nervous system
1D00Infectious encephalitis, not elsewhere classified
1D01Infectious meningitis, not elsewhere classified
1D02Infectious myelitis, not elsewhere classified
1D03Infectious abscess of the central nervous system
1D04Infectious granulomas of the central nervous system
1D05Infectious cysts of the central nervous system
1D0YOther specified non-viral and unspecified infections of the central nervous system
1D0ZNon-viral and unspecified infections of the central nervous system, unspecified
1D20-1D2Z
Dengue
1D40-1D4Z
Certain arthropod-borne viral fevers
1D40Chikungunya virus disease
1D41Colorado tick fever
1D42O'nyong-nyong fever
1D43Oropouche virus disease
1D44Rift Valley fever
1D45Sandfly fever
1D46West Nile virus infection
1D47Yellow fever
1D48Zika virus disease
1D49Crimean-Congo haemorrhagic fever
1D4AOmsk haemorrhagic fever
1D4BKyasanur Forest disease
1D4CAlkhurma haemorrhagic fever
1D4DRoss River disease
1D4ESevere fever with thrombocytopenia syndrome
1D4YOther specified arthropod-borne viral fevers
1D4ZArthropod-borne viral fever, virus unspecified
1D60-1D6Z
Certain zoonotic viral diseases
1D80-1E1Z
Certain other viral diseases
1D90-1D9Z
Viral infection of unspecified site
1E30-1E32
Influenza
1E50-1E5Z
Viral hepatitis
1E70-1E7Z
Infections due to poxvirus
1E70-1F0Z
Viral infections characterised by skin or mucous membrane lesions
1F00Herpes simplex infections
1F01Roseola infantum
1F02Rubella
1F03Measles
1F04Erythema infectiosum
1F05Picornavirus infections presenting in the skin or mucous membranes
1F0YOther specified viral infections characterised by skin or mucous membrane lesions
1F0ZViral infections characterised by skin or mucous membrane lesions, unspecified
1E80-1E8Z
Human papillomavirus infection of skin or mucous membrane
1E90-1E91
Varicella zoster virus infections
1F20-1F2Z
Mycoses
1F20Aspergillosis
1F21Basidiobolomycosis
1F22Blastomycosis
1F23Candidosis
1F24Chromoblastomycosis
1F25Coccidioidomycosis
1F26Conidiobolomycosis
1F27Cryptococcosis
1F28Dermatophytosis
1F29Eumycetoma
1F2AHistoplasmosis
1F2BLobomycosis
1F2CMucormycosis
1F2DNon-dermatophyte superficial dermatomycoses
1F2EParacoccidioidomycosis
1F2FPhaeohyphomycosis
1F2GPneumocystosis
1F2HScedosporiosis
1F2JSporotrichosis
1F2KTalaromycosis
1F2LEmmonsiosis
1F2YOther specified mycoses
1F2ZMycoses, unspecified
1F40-1F4Z
Malaria
1F40-1G2Z
Parasitic diseases
1F50-1F5Z
Nonintestinal protozoal diseases
1F60-1F6Z
Diseases due to nematodes
1F60Angiostrongyliasis
1F61Anisakiasis
1F62Ascariasis
1F63Capillariasis
1F64Dracunculiasis
1F65Enterobiasis
1F66Filariasis
1F67Gnathostomiasis
1F68Hookworm diseases
1F69Oesophagostomiasis
1F6AOnchocerciasis
1F6BStrongyloidiasis
1F6CSyngamosis
1F6DToxocariasis
1F6ETrichinosis
1F6FTrichostrongyliasis
1F6GTrichuriasis
1F6HUncinariosis
1F6YOther specified diseases due to nematodes
1F6ZDiseases due to nematodes, unspecified
1F60-1F9Z
Helminthiases
1F70-1F7Z
Diseases due to cestodes
1F80-1F8Z
Diseases due to trematodes
1G00-1G0Z
Infestations by ectoparasites
1G40-1G41
Sepsis
1G80-1G8Z
Sequelae of infectious diseases
Frequently Asked Questions
What ICD-11 codes are in Chapter 1?
Chapter 1: Certain Infectious or Parasitic Diseases covers ICD-11 codes 1A00-1H0Z. It contains 43 code blocks with 342 top-level categories.
What conditions does ICD-11 Chapter 1 cover?
Covers infections caused by bacteria, viruses, fungi, and parasites, including gastroenteritis, tuberculosis, HIV, sexually transmitted infections, and viral hepatitis. ICD-11 reorganizes infectious diseases with updated classification of antimicrobial resistance and emerging infections. This chapter includes codes from 1A00-1H0Z.
How is ICD-11 Chapter 1 different from ICD-10?
ICD-11 reorganized many chapters compared to ICD-10. Chapter 1 (Certain Infectious or Parasitic Diseases) may include conditions that were in different ICD-10 chapters, and some conditions previously here may have moved. ICD-11 also adds new chapters for sleep-wake disorders, sexual health, and traditional medicine that did not exist in ICD-10.
How many code blocks are in ICD-11 Chapter 1?
Chapter 1 has 43 code blocks: 1A00-1A0Z (Bacterial intestinal infections), 1A00-1A40 (Gastroenteritis or colitis of infectious origin), 1A10-1A1Z (Bacterial foodborne intoxications), 1A20-1A2Z (Viral intestinal infections), and 39 more.
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