Specialty3 min read

Infectious diseases

Detail level

An infectious disease specialist is an expert in diagnosing and treating diseases caused by microorganisms: bacteria, viruses, fungi and parasites.

MedlinePlus describes this specialty as concerned with infections that affect the tissues of any part of the body. According to the American Medical Association, infectious disease specialists work as "medical detectives" who identify the cause of an infection and decide on effective treatment, including choosing the antibiotic, its duration and route of administration and monitoring its side effects.

These doctors collaborate with other specialties, and play a role in public health crises, epidemiological surveillance and infection prevention (AMA). On this site, the pages on pneumonia, viral hepatitis and the immune system are linked to the specialty. The two professional sources (Grade 4) are descriptive, so the page does not set treatment protocols.

In one minute¹²³

What is it?: The specialty of diagnosing and treating infections caused by micro-organisms.
Who is usually affected?: People with complex or resistant infections or infections in more than one organ, or who need an antibiotic plan.
Acute or chronic?: Varies according to the infection.
Main symptoms: Fever, fatigue and symptoms depending on the site of infection.
Red flags?: Yes: fever with confusion, a stiff neck or shortness of breath is an emergency.
Preventable?: Hygiene and appropriate vaccines according to the recommendations of health bodies.

What is it?

An "expert in the diagnosis and treatment of diseases caused by micro-organisms", including bacteria, viruses (such as HIV and hepatitis), fungi and parasites (AMA). MedlinePlus describes it as infections that affect the tissues of any part of the body.

Conditions it covers

The American Medical Association lists: meningitis, Clostridioides difficile infection, HIV, viral hepatitis, tuberculosis, malaria, and emerging infections such as Zika and Ebola.

Related pages on this site: pneumonia, viral hepatitis, the immune system and the lymphatic system.

Common tests and procedures

According to the AMA their work includes identifying the cause of an infection, choosing the appropriate antibiotic and the duration and route of treatment, monitoring side effects, working with other specialties and participating in public health, surveillance and infection control.

When to see one

Referral to the specialist is usually decided by the primary care provider according to the condition (MedlinePlus). This page does not cover specific referral criteria for this specialty.

Common questions

Do I need an infectious disease specialist for every infection?

No; many simple infections are treated by the primary care provider, and the patient is referred when complex according to the doctor's judgement (MedlinePlus).²

Questions for your doctor

What is the cause of the infection, and how do I confirm it with tests?
How long is the antibiotic course, and does it have side effects?
Do I need isolation measures or testing of contacts?
Which vaccines are recommended for me?

References

1
American Medical Association. Infectious diseases — specialty description. www.ama-assn.org/specialty/infectious-diseases
Educational & historical references · Accessed 2026-10-06
2
MedlinePlus. Types of health care providers. medlineplus.gov/ency/article/001933.htm
Health agencies & guidelines · Accessed 2026-10-06
3
Infectious Diseases Society of America. Infectious Diseases Society of America. www.idsociety.org/
Educational & historical references · Accessed 2026-10-06

Review status: Edited content · Last updated: 2026-10-06

Change log

2026-10-06 — Page created.

Educational content only — no diagnosis, and no substitute for a clinician.

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