What is the first line of defense against infection?

The first line of defense against infection is the skin. The skin serves as a physical barrier that protects the internal organs from pathogens, such as bacteria and viruses, which can cause infection. It has several protective features, including its tough outer layer and the presence of antimicrobial substances that inhibit the growth of microorganisms.

In addition to its physical barrier, the skin plays a critical role in the immune response by releasing chemicals that can trap or kill infectious agents. When the skin is intact, it effectively prevents many pathogens from entering the body, thereby reducing the risk of infection.

While hand hygiene is crucial in preventing the spread of infections, especially in healthcare settings, it is considered a secondary line of defense, primarily focused on removing pathogens after they may have come into contact with the skin. The immune system becomes activated only after a potential infection has occurred, meaning it acts as an internal defense rather than the initial barrier. Protective equipment, while important in specific circumstances, also serves primarily to supplement other defenses rather than prevent infection at the first point of entry.