What type of diseases are transmitted through direct or indirect contact between humans?

Infectious diseases are caused by pathogens such as bacteria, viruses, fungi, or parasites that can be transmitted from one person to another through direct contact (e.g., touching, kissing, sexual contact) or indirect contact (e.g., touching contaminated surfaces or sharing utensils). These diseases can spread easily in community settings, emphasizing the importance of hygiene practices, vaccinations, and understanding transmission pathways to prevent outbreaks.

In contrast, chronic diseases are long-term conditions that typically do not arise from infectious agents, such as diabetes or heart disease. Autoimmune diseases occur when the body's immune system mistakenly attacks healthy cells, and genetic diseases are caused by abnormalities in an individual's DNA, which are not transmitted through contact with others but rather inherited. This context highlights why the classification of diseases based on their transmission methods is critical in public health and epidemiology.