What is the invasion of body by a disease producing organism?

The invasion of the body by a disease-producing organism is known as infection. Infections can be caused by various types of microorganisms, including bacteria, viruses, fungi, and parasites. These organisms can enter the body through different routes, such as the respiratory tract, digestive tract, skin, or through direct contact with infected individuals or animals. Once inside the body, these microorganisms can multiply and spread, leading to tissue damage and illness. Infections can range from mild and self-limiting to severe and life-threatening. Understanding the causes and mechanisms of infection is crucial for effective prevention and treatment of diseases.