Health: The Ultimate Treasure - Treatment of diseases

Health is defined by the WHO as a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.

Principles of Treatment: There are two ways to treat an infectious disease: (i) To reduce the effects of the disease (symptomatic treatment like reducing fever using antipyretics), and (ii) To kill the cause of the disease (using medicine to kill the pathogen).

Antibiotics: These are chemical substances that block biochemical pathways important for bacteria. For example, $Penicillin$ blocks the bacterial processes that build the cell wall.

Antiviral Drugs: These are more difficult to make than antibacterial drugs because viruses have few biochemical mechanisms of their own and enter the host cells to use the host's machinery ($DNA/RNA$ replication).

Principles of Prevention: General ways involve preventing exposure (e.g., providing clean drinking water to prevent water-borne diseases like $Cholera$). Specific ways involve immunization through vaccines.

Vaccination: The process of introducing a weakened or dead pathogen into the body to train the immune system. This relies on the property of 'memory' in the immune system.

Pathogens: Organisms that cause diseases, including bacteria, viruses, fungi, protozoans (e.g., $Plasmodium$ causing Malaria), and worms.