The Biggest Public Health Threat Is Not a Virus but a Weakened Immune System
The innate immune system is the first and not specific defense mechanism. It stops potential disease-causing organisms. This system is formed by physical barriers, such as skin, saliva, and mucous membranes. Switching to the adaptive immune system happens when the pathogen is able to break through the first barrier. Cells from the innate immune system present the pieces of the pathogen or foreign substance to B Cells and T cells of the adaptive immune system.