Question

Comment upon the following: Infectious disease.

Hint:

Infectious disease needs a living pathogen that can pass from one host to another.

Answer 1

Step 1: Understanding the Concept:
Not every disease is caused by an outside organism; some come from internal causes like nutrient deficiency or genetics. Infectious diseases are specifically the kind caused by outside agents.

Step 2: Define it.
An infectious disease is one caused by a pathogenic microorganism, such as a bacterium, virus, fungus, or protozoan parasite, that enters and multiplies inside the body.

Step 3: Note the key feature.
Because the causal agent is a living microorganism, such diseases can spread from an infected person to a healthy person, either directly (through contact, air, or body fluids) or indirectly (through contaminated food, water, or a carrier organism).

Final Answer:
Infectious diseases are caused by pathogens and, unlike non-infectious diseases, can be transmitted from one person to another.