Infectious diseases, also known as infectiology, are a specialized medical procedure responsible for the diagnosis, control, and treatment of diseases. The effectiveness of an infectious disease specialist may be more controlling for nosocomial infections (hospitalized), or it may be patient-based.

Infectious disease specialists often act as advisors to other physicians in cases of complex illnesses, and often treat patients with HIV / AIDS and other vaccines. Although most common infections are treated by doctors without formal expertise in communicable diseases, specialists can be diagnosed in cases where the infection is difficult to diagnose or treat. They may also be asked to help identify the cause of the flu of unknown origin.

Infectious disease specialists can use both hospitals (chronic patients) and clinics (outpatients). Hospitals, specialists in infectious diseases assist in ensuring timely diagnosis and treatment of severe infections by recommending appropriate tests to identify the source of infection and by recommending appropriate authorities such as distributing antiviral drugs. For certain types of diseases, professional involvement in infectious diseases can improve patient outcomes. At clinics, specialists in infectious diseases can provide long-term care for patients with chronic illnesses such as HIV / AIDS.