Health and Disease: A Comprehensive Analysis

Health and Disease

Physical Health

Physical health: the general condition of the body. Good physical health means the body systems are working properly. Many factors, such as biology or genetics, affect an individual’s physical health.

Mental Health

Mental health: the way a person feels, thinks, and deals with daily life. People with good mental health maintain an emotional and psychological balance in their lives.

Social Well-being

Social well-being: a state in which basic human needs are met. It involves relationships with others and how a person interacts and socializes in the community. According to the WHO, peace, food, education, and housing are essential for social well-being.

What is a Disease?

A disease is a change in the body that produces a loss of health.

Key Terms

Etiology: In medicine, the study of the causes of a disease.

Symptom: Subjective evidence of disease as perceived by the patient, such as pain or fatigue.

Sign: Objective evidence of disease as observed by a doctor or nurse, such as fever.

Doctors take into account symptoms, signs, and specific tests to diagnose diseases and recommend treatment.

Classification of Diseases

Infectious Diseases

Caused by pathogens. A pathogen enters the body and reproduces, causing an infection.

Non-Infectious Diseases

Transmission of Infectious Diseases

Key Components

Agent: The pathogen that causes a disease (a virus, bacteria, fungi, or protozoa).

Reservoir: The place where the pathogen lives and usually reproduces. Reservoirs can be environmental or a person. To leave the reservoir, a pathogen requires a portal of exit.

Vector: The person, animal, or microorganism that carries and transmits the agent or pathogen. Vectors are not necessarily infected by the disease. Some animals can be both vector and reservoir, such as rats.

Host: The organism that is infected. A pathogen must be able to cross a portal of entry: physical barriers that protect the body.


Transmission of Pathogens

Direct Contact

Transmission from person to person. Pathogens pass from an infected person to a healthy person by direct contact.

Indirect Contact

Transmission by vehicle, vector, or through the air. Pathogens are transmitted to a person by vehicles like objects.

Surface Barriers

Physical Barriers

Body skin and mucous membranes.

Chemical Barriers

Substances that prevent growth, such as tears and saliva.

Biological Barriers

Bacteria that compete for food and space with pathogens.

Specific Immune Response

Lymphocytes recognize antigens.

Prevention and Treatment of Infectious Diseases

Prevention

Personal and environmental hygiene, sexual health, good hygiene, vaccinations, preventive measures for traveling, pet care.

Treatment

  • Bacteria: Antibiotics
  • Viruses: Antibodies/Antivirals
  • Fungi: Antifungals
  • Protozoa: Special medications

Prevention of Non-Infectious Diseases and Disorders

Risk Factors

  • Unbalanced diets: Defects or excesses of nutrients
  • Environmental factors: Chemical and biological exposure to chemicals or metals. Water pollution contributes to cardiovascular issues.
  • Risky behaviors: Alcohol, drugs

Healthy Habits

  • Use suitable light
  • Protect the eyes and the skin from solar radiation
  • Exercise
  • Get enough sleep and rest