Which term describes the movement of pathogens from one person to another?

• A. vaccination
• B. immunity
• C. transmission
• D. outbreak

Answer: (C)

Transmission is the movement of pathogens from one person to another. It covers how microbes spread from an infected person to others through direct contact, indirect contact via contaminated surfaces, droplets from coughing or sneezing, airborne spread, sexual contact, vertical transfer from mother to child, or via vectors like insects. This is different from vaccination, which introduces a vaccine to stimulate the immune system; immunity, which is the protective state that reduces or prevents infection; and an outbreak, which is a surge of cases in a population. Understanding transmission helps explain why infection-control measures such as hand hygiene, masks, safe-sex practices, and isolation are used to interrupt those routes and prevent spread.