ICD-10 Chapter I: Certain infectious and parasitic diseases

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International Statistical Classification of Diseases and Related Health Problems 10th Revision
I A00–B99 Certain infectious and parasitic diseases
II C00–D48 Neoplasms
III D50–D89 Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
IV E00–E90 Endocrine, nutritional and metabolic diseases
V F00–F99 Mental and behavioural disorders
VI G00–G99 Diseases of the nervous system
VII H00–H59 Diseases of the eye and adnexa
VIII H60–H95 Diseases of the ear and mastoid process
IX I00–I99 Diseases of the circulatory system
X J00–J99 Diseases of the respiratory system
XI K00–K93 Diseases of the digestive system
XII L00–L99 Diseases of the skin and subcutaneous tissue
XIII M00–M99 Diseases of the musculoskeletal system and connective tissue
XIV N00–N99 Diseases of the genitourinary system
XV O00–O99 Pregnancy, childbirth and the puerperium
XVI P00–P96 Certain conditions originating in the perinatal period
XVII Q00–Q99 Congenital malformations, deformations and chromosomal abnormalities
XVIII R00–R99 Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
XIX S00–T98 Injury, poisoning and certain other consequences of external causes
XX V01–Y98 External causes of morbidity and mortality
XXI Z00–Z99 Factors influencing health status and contact with health services
XXII U00–U99 Codes for special purposes

ICD-10 is an international statistical classification used in health care and related industries.

ICD-10 is the 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD), a medical classification list by the World Health Organization (WHO). It contains codes for diseases, signs and symptoms, abnormal findings, complaints, social circumstances, and external causes of injury or diseases. Work on ICD-10 began in 1983, became endorsed by the Forty-third World Health Assembly in 1990, and was first used by member states in 1994.

Medical classification, or medical coding, is the process of transforming descriptions of medical diagnoses and procedures into universal medical code numbers. The diagnoses and procedures are usually taken from a variety of sources within the health care record, such as the transcription of the physician's notes, laboratory results, radiologic results, and other sources.

Health care Prevention of disease and promotion of wellbeing

Health care or healthcare is the maintenance or improvement of health via the prevention, diagnosis, and treatment of disease, illness, injury, and other physical and mental impairments in people. Health care is delivered by health professionals in allied health fields. Physicians and physician associates are a part of these health professionals. Dentistry, midwifery, nursing, medicine, optometry, audiology, pharmacy, psychology, occupational therapy, physical therapy and other health professions are all part of health care. It includes work done in providing primary care, secondary care, and tertiary care, as well as in public health.


Produced by the World Health Organization, it is used in several countries around the world. Some have gone on to develop their own national enhancements, building off the international classification.

World Health Organization Specialised agency of the United Nations

The World Health Organization (WHO) is a specialized agency of the United Nations that is concerned with international public health. It was established on 7 April 1948, and is headquartered in Geneva, Switzerland. The WHO is a member of the United Nations Development Group. Its predecessor, the Health Organisation, was an agency of the League of Nations.

Chapter I of ICD-10 deals with certain infections and parasitic diseases. Infections specific to a body system are found in other chapters, for example cellulitis is found in Chapter XII.

Cellulitis Human disease

Cellulitis is a bacterial infection involving the inner layers of the skin. It specifically affects the dermis and subcutaneous fat. Signs and symptoms include an area of redness which increases in size over a few days. The borders of the area of redness are generally not sharp and the skin may be swollen. While the redness often turns white when pressure is applied, this is not always the case. The area of infection is usually painful. Lymphatic vessels may occasionally be involved, and the person may have a fever and feel tired.

ICD-10 is an international statistical classification used in health care and related industries.

A00–A79 – Bacterial infections, and other intestinal infectious diseases, and STDs

(A00–A09) Intestinal infectious diseases

Cholera Bacterial infection of the small intestine

Cholera is an infection of the small intestine by some strains of the bacterium Vibrio cholerae. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea that lasts a few days. Vomiting and muscle cramps may also occur. Diarrhea can be so severe that it leads within hours to severe dehydration and electrolyte imbalance. This may result in sunken eyes, cold skin, decreased skin elasticity, and wrinkling of the hands and feet. Dehydration can cause the skin to turn bluish. Symptoms start two hours to five days after exposure.

Typhoid fever A bacterial infectious disorder contracted by consumption of food or drink contaminated with Salmonella typhi. This disorder is common in developing countries and can be treated with antibiotics.

Typhoid fever, also known simply as typhoid, is a bacterial infection due to Salmonella typhi that causes symptoms. Symptoms may vary from mild to severe and usually begin six to thirty days after exposure. Often there is a gradual onset of a high fever over several days; weakness, abdominal pain, constipation, headaches, and mild vomiting also commonly occur. Some people develop a skin rash with rose colored spots. In severe cases there may be confusion. Without treatment, symptoms may last weeks or months. Diarrhea is uncommon. Other people may carry the bacterium without being affected; however, they are still able to spread the disease to others. Typhoid fever is a type of enteric fever, along with paratyphoid fever.

Paratyphoid fever bacterial infection caused by one of the three types of Salmonella enterica

Paratyphoid fever, also known simply as paratyphoid, is a bacterial infection caused by one of the three types of Salmonella enterica. Symptoms usually begin 6–30 days after exposure and are the same as those of typhoid fever. Often, a gradual onset of a high fever occurs over several days. Weakness, loss of appetite, and headaches also commonly occur. Some people develop a skin rash with rose-colored spots. Without treatment, symptoms may last weeks or months. Other people may carry the bacteria without being affected; however, they are still able to spread the disease to others. Both typhoid and paratyphoid are of similar severity. Paratyphoid and typhoid fever are types of enteric fever.

(A15–A19) Tuberculosis

(A20–A28) Certain zoonotic bacterial diseases

(A30–A49) Other bacterial diseases

(A50–A64) Infections with a predominantly sexual mode of transmission

(A65–A69) Other spirochaetal diseases

(A70–A74) Other diseases caused by chlamydiae

(A75–A79) Rickettsioses

A80–B34 – Viral infections

(A80–A89) Viral infections of the central nervous system

(A90–A99) Arthropod-borne viral fevers and viral haemorrhagic fevers

(B00–B09) Viral infections characterized by skin and mucous membrane lesions

(B15–B19) Viral hepatitis

(B20–B24) Human immunodeficiency virus (HIV) disease

(B25–B34) Other viral diseases

B35–B89 – Infections caused by fungi, protozoans, worms, and infestations

(B35–B49) Mycoses

(B50–B64) Protozoal diseases

(B65–B83) Helminthiases

(B85–B89) Pediculosis, acariasis and other infestations

B90–B99 – Sequelae, and diseases classified elsewhere

(B90–B94) Sequelae of infectious and parasitic diseases

(B95–B97) Bacterial, viral and other infectious agents

(B99) Other infectious diseases


See also

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ICD-10 is an international statistical classification used in health care and related industries.

ICD-10 is an international statistical classification used in health care and related industries.

ICD-10 is an international statistical classification used in health care and related industries.

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