How do host defend themselves from parasites?

Hosts defend themselves from parasites through various mechanisms, including physical barriers like skin and mucous membranes that prevent entry. The immune system plays a crucial role by recognizing and attacking parasites using specialized cells and antibodies. Additionally, behavioral adaptations, such as grooming or avoiding infested areas, help reduce exposure to parasites. Some hosts also develop tolerance, allowing them to coexist with certain parasites without suffering significant harm.