An internist, often known as an internal medicine doctor, is a doctor who specialises in internal medicine. Internal medicine focuses on injury and disease prevention, diagnosis, and treatment. Internal medicine specialists are educated to diagnose and treat common diseases, acute and chronic illnesses, and difficult diagnostic issues. Internal medicine doctors concentrate in the treatment of adults within general medicine, while they may have additional training in subspecialties such as infectious illnesses. Infectious disease medicine is an internal medicine discipline that focuses on the diagnosis and treatment of infections. Although general internists and other specialty physicians treat the majority of infections, infectious disease internists are regularly called upon to help diagnose unknown illnesses and manage difficult, uncommon, or severe infections. Infectious disease medicine necessitates a thorough grasp of how bacterial, viral, fungal, and parasite illnesses manifest clinically in humans, as well as knowledge of antimicrobial medicines, antibiotic resistance, vaccines, and other immunobiological agents.