Residency applications are now open! Be sure to review and finalize your top program selections on FREIDA™.

Search Programs
Explore Specialties
Tools & Resources
Program Director Portal
Infectious Disease (IM)
Training Information

Specialty Description

An infectious disease specialist is an expert in the diagnosis and treatment of diseases caused by microorganisms, including bacteria, viruses (such as HIV and hepatitis), fungi and parasites. 

Within the infectious diseases subspecialty there are a variety of career paths to choose from, including clinical practice (e.g., private practice, clinics or hospitals), basic and clinical research, public health, and health care epidemiology. The work of ID clinicians may involve consultations or—for those who see patients with chronic infections such as HIV or viral hepatitis—long-term relationships that include managing a patient’s overall care.

ID specialists have the expertise to quickly identify and treat potentially life-threatening infections. In hospital settings, ID specialists are frequently called for consultations for patients with severe infections such as meningitis or Clostridium difficile because these patients tend to have better outcomes  when seen early by an ID specialist. ID specialists also play an important role in overseeing transitions of care from the hospital to the  community.

With an emphasis on optimizing health system performance, ID specialists can be expected to take on a greater role in the context of health care reform. In hospitals and health care systems, ID specialists often oversee infection control (e.g., preventing health care-associated infections), antibiotic stewardship, use of diagnostic tests, radiology services, micro-lab services and hazardous waste management.

An estimated 8,300 ABIM-certified and 1,553 pediatric board-certified ID specialists are practicing in the United States today, which has grown from fewer than 1,000 physicians in the early 1980s.

What is an infectious disease (ID) specialist?

An infectious disease (ID) specialist is (see below, “Subspecialty/Fellowship Training”*) an expert in the diagnosis and treatment of diseases caused by microorganisms, including bacteria, viruses (such as HIV and hepatitis), fungi and parasites. Known as “medical detectives,” ID specialists solve complicated cases by identifying the causes of infection and the most effective treatment. ID specialists often work alongside general internists and pediatricians as well as other medical and surgical specialists, lending their expertise to the treatment of infections in major organ systems (e.g., cardiovascular, central nervous system, circulatory, etc.).

What does an infectious disease (ID) specialist do?

Infectious diseases are the second leading cause of death worldwide and ID specialists are on the cutting edge of some of the hottest topics in medicine today—from the growing threat posed by antibiotic resistance, to global health problems such as tuberculosis and malaria, to emerging infections such as Zika virus, pandemic influenza or Ebola.

This dynamic and evolving discipline offers exciting opportunities for physicians who enjoy helping others through problem-solving and medical detective work.

ID specialists play a critical role in the treatment and prevention of infections by managing appropriate antibiotic choice, duration of therapy, route of delivery, and adverse drug reactions. ID specialists are commonly called upon in major public health crises or outbreaks, during which their role is to educate the public, define treatment, and help halt the spread of rapidly communicable illnesses. Diseases that used to have high morbidity and mortality rates, such as polio, smallpox, measles, influenza, mumps, and rubella, have been significantly curtailed or eradicated thanks to traditional ID strategies of surveillance and immunization.