Final answer:
Reservoir signifies where a pathogen normally exists, a vector is an organism that transmits infections, and contact tracing is a method used to identify and manage individuals who may have been exposed to infectious diseases.
Step-by-step explanation:
Reservoir refers to any person, animal, plant, soil, or substance in which an infectious agent normally lives and multiplies. It is where the pathogen typically resides and serves as a source of infection for other organisms. A vector, in the context of infectious disease, is a living organism that transmits an infectious agent from an infected host to a new host. Common examples of vectors include mosquitoes, ticks, and fleas. Finally, contact tracing is a public health strategy used to control the spread of diseases. It involves identifying and following up with individuals who have been in close contact with someone who has been diagnosed with an infectious disease, aiming to interrupt disease transmission and reduce the spread of infection.
Contact tracing is particularly crucial during outbreaks and has been widely applied during the COVID-19 pandemic. By tracking down contacts, health professionals can ensure that they receive necessary care and guidance, such as being tested for the disease, undergoing quarantine, or monitoring for symptoms.