Infectious Diseases

Physicians who treat infectious diseases (ID) are called infectious disease specialists. Generally, infectious disease is considered a subspecialty of internal medicine. Rather than treating one specific part of the body, ID specialists treat the whole body. Training in internal medicine provides infectious disease specialists with a broad working knowledge of and experience in treating multiple organs and their appropriate systems – heart and cardiovascular system, brain and the neurological system, lungs and pulmonary system, the urinary tract and digestive system, and the immune system.  These same systems are regularly affected by infectious diseases.   

Some infectious disease specialists, because of the wide variety of diseases, causes, and symptoms, have chosen to specialize in treating and diagnosing specific diseases, such as HIV/AIDS. Many infectious disease specialists have also chosen to work in tropical areas and developing countries, treating many familiar diseases like polio and malaria that are not prevalent in the United States, and others work with organizations like the Centers for Disease Control and the World Health Organization. 

Infectious diseases are caused by bacteria, viruses, fungi, and parasites.  They can be passed from person to person; they can be acquired through animal or insect bites; or they can be ingested through contaminated food and water.  Infectious diseases, especially those passed through insect bites (malaria, dengue fever, and West Nile fever) and contaminated food and water (cholera), are especially prevalent in developing nations. 

The diseases that infectious disease specialists treat can be rare, Creutzfeldt-Jakob disease – the human version of mad cow disease – and Ebola, for instance.  They can also be quite prevalent and familiar: any strain of hepatitis, gonorrhea, herpes and most other sexually transmitted diseases, the flu, pelvic inflammatory diseases, pneumonia, and shingles are all infectious diseases with high rates of incidence that specialists diagnose and treat. 

In the United States, many infectious diseases like hepatitis A and B, chickenpox, polio, influenza, diphtheria, mumps, measles, and rubella, and meningitis can be prevented through vaccination.   

Board Certification and Training of Infectious Disease Specialists

Infectious disease specialists are generally trained and board certified in internal medicine.  Occasionally, infectious disease specialists have been trained and board certified in pediatrics.  Following certification in either internal medicine or pediatrics, ID specialists complete a two-year fellowship program with at least twelve months of clinical practice.  During the fellowship, physicians evaluate diagnostic specimens used to diagnose diseases, maintain and manage patient catheters, and administer antibiotics. They also receive training in immunology (how the body’s immune system works and responds to the diseases the specialist is treating) and epidemiology (how disease spreads), and study the human body’s response to the antibiotics and vaccinations used to treat and prevent infectious diseases. 

In addition to their board certification through the American Board of Internal Medicine, infectious disease specialists may belong to professional associations such as the Infectious Disease Society of America, the American Autoimmune Related Diseases Association, and the Pediatric Infectious Diseases Society.  Physicians may also be active in non-profit, public health associations that address infectious disease like the Lyme Disease Foundation and those that address AIDS/HIV. 

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