NEET BIOLOGY

Detailed explanation-1: -Infectious diseases are disorders caused by organisms-such as bacteria, viruses, fungi or parasites. Many organisms live in and on our bodies. They’re normally harmless or even helpful. But under certain conditions, some organisms may cause disease.

Detailed explanation-2: -Infectious diseases are illnesses caused by germs (such as bacteria, viruses, and fungi) that enter the body, multiply, and can cause an infection. Some infectious diseases are contagious (or communicable), meaning they are capable of spreading from one person to another.

Detailed explanation-3: -Infectious diseases are caused by pathogens, which include bacteria, fungi, protozoa, worms, viruses, and even infectious proteins called prions. Pathogens of all classes must have mechanisms for entering their host and for evading immediate destruction by the host immune system. Most bacteria are not pathogenic.

Detailed explanation-4: -Infectious diseases are illnesses caused by the spread of microorganisms (bacteria, viruses, fungi or parasites) or prions to humans from other humans, animals or the environment, including food and water.