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Transmission and Creation of Infectious Disease

 

Infectious diseases are diseases caused by microorganisms (bacteria, viruses, fungi, parasites) that can spread from one person, animal, or environment to another.

How Diseases Spread (Transmission)

  • Direct contact – Touching an infected person.

  • Airborne – Through coughing or sneezing.

  • Water and food – Drinking or eating contaminated food or water.

  • Vector-borne – Spread by mosquitoes, ticks, or flies.

  • Blood and body fluids – Through infected blood or body fluids.

Creation (Occurrence) of Infectious Disease

Disease occurs when:

  • A pathogen enters the body.

  • The person's immunity is weak.

  • The environment is favorable (poor sanitation, pollution, overcrowding).

Important Scholars

Scholar Year Contribution
Louis Pasteur 1861 Proposed the Germ Theory of Disease.
Robert Koch 1882 Identified disease-causing bacteria and developed Koch's Postulates.
John Snow 1854 Showed that cholera spreads through contaminated water.

Nutrition and Health 

Nutrition is the process of obtaining and using food nutrients for growth, energy, and good health.

Importance of Good Nutrition

  • Builds strong immunity.

  • Supports growth and development.

  • Prevents malnutrition and deficiency diseases.

  • Reduces the risk of many illnesses.

Types of Nutrients

  • Carbohydrates – Energy

  • Proteins – Growth and repair

  • Fats – Energy storage

  • Vitamins – Body regulation

  • Minerals – Healthy bones and body functions

  • Water – Essential for all body processes

Important Scholars

Scholar Year Contribution
James Lind 1747 Showed that citrus fruits prevent scurvy (Vitamin C deficiency).
Casimir Funk 1912 Coined the term Vitamin.
Wilbur Olin Atwater 1894 Developed the Atwater system for measuring food energy (calories).



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