Biology - Diseases and First Aid (Communicable and Non-communicable diseases)

Disease is defined as a departure from a state of health, involving a disruption in the normal functioning of the body or mind.

Communicable diseases are caused by pathogens such as $Bacteria$, $Viruses$, $Protozoa$, and $Fungi$, and can be transmitted from an infected person to a healthy person via air, water, food, or vectors like the female $\textit{Anopheles}$ mosquito.

Non-communicable diseases are not transmitted from person to person; they include deficiency diseases (e.g., Goitre due to lack of $I_2$), metabolic disorders (e.g., Diabetes Mellitus), and lifestyle diseases like Hypertension.

Immunity is the body's ability to resist and fight infections, which can be natural or acquired through vaccination. Vaccines stimulate the production of antibodies against specific antigens.

Pathogens like $\textit{Mycobacterium tuberculosis}$ (Tuberculosis) and $\textit{Vibrio cholerae}$ (Cholera) represent bacterial threats, while diseases like AIDS are caused by the $HIV$ (Human Immunodeficiency Virus).

First Aid for burns involves immediate cooling with running $H_2O$, while first aid for fractures requires immobilization using a splint to prevent further injury.

Oral Rehydration Solution ($ORS$) is essential in treating dehydration caused by diseases like Cholera and Diarrhoea to maintain the electrolyte balance of $Na^+$ and $Cl^-$ ions.