👉 A harmful fluid, often referred to as a pathogen or infectious agent, is a substance that can cause disease in living organisms. These can include bacteria, viruses, fungi, parasites, and other microorganisms that invade the body, disrupt normal cellular functions, and lead to illness. When a harmful fluid enters the body, it can trigger an immune response, causing inflammation, tissue damage, and potentially life-threatening complications if left untreated. Examples of harmful fluids include blood-borne pathogens like HIV or hepatitis viruses, which can spread through bodily fluids such as blood, semen, or saliva, and airborne pathogens like those causing tuberculosis. The body's immune system plays a crucial role in fighting these invaders, but sometimes the harmful fluid overwhelms the defenses, leading to infection and disease.
