Chapter 1 - Introduction

Abstract

There are approximately 5000 practicing allergists/immunologists in the United States, and several thousand in Europe and the rest of the world. The United States has a well-established process to matriculate board certified allergists and immunologists through clinical training that includes medical school, and internal medicine or pediatric residency, and finally a 2- or 3-year fellowship in allergy and immunology. In the 21st century, immunology is at the center of medicine, as it is becoming more and more obvious that the immune system is involved in general health and the health of all organ systems in the body. The immune system consists of numerous chemicals, cells, pathways, and networks that all have to operate in harmony in order to preserve health. Like all living entities, the immune system goes through development, maturity, and senescence. Thus the immune system functions differently at different ages of an organism. The immune system can be affected by genetics and the environment and the interaction between the two, a concept known as epigenetics. As allergists and immunologists, we interact with almost all other specialists, including pulmonologists, rheumatologists, dermatologists, otolaryngologists, and infectious disease specialists. Our specialty is supported by several professional organizations across the world, and there are multiple journals in allergy and immunology that publish a variety of subtopics of interest to us. Allergy and immunology is at the cutting edge of medicine and it is a particularly exciting field because it is constantly changing, with new discoveries made every day. The recent COVID-19 pandemic has further enhanced the role of immunologists in medicine, as we gain increased understanding of the pathogenic role of the immune system in morbidity and mortality seen in infections.