Health, Disease, and the Human Body
Health
Health is a state of well-being and optimal social functioning, encompassing both physical and mental aspects. Determinants of health include:
- Lifestyle and health behaviors: Avoiding tobacco, alcohol, and drugs; maintaining good nutrition; and engaging in regular physical exercise.
- Environment: Social, physical, and psychological factors.
- Biology: Aging, constitution, and inheritance.
- Systems of healthcare: Prevention, rehabilitation, and healing.
- Social acceptance: Being accepted or not accepted.
Risk Factors
A risk factor is any detectable characteristic of a person or group that is associated with the probability of developing or producing a disease.
Types of factors:
- Those which can be modified: Alcohol consumption, poor diet, etc.
- Those which cannot be changed: Age, sex, or heredity.
Preventive Medicine
Preventive medicine is a branch of medicine concerned with preventing the appearance, development, and maintenance of disease in individuals, families, or groups. It is based on the knowledge of medical science. Levels of Prevention:
- Primary Prevention: Assistance aimed at minimizing risk factors and the subsequent development of disease. Example: Vaccines.
- Secondary Prevention: Avoiding clinical manifestations of a disease through early detection.
- Tertiary Prevention: Assistance designed to improve the clinical course of a disease and avoid complications and the damage it causes.
Pathology and Illness
Pathology: Changes occurring in the body because of an illness.
Illness: A physical or mental disorder that causes disturbances in normal body functions, either physical or psychological.
- Infectious: Produced by pathogens.
- Non-infectious: Not produced by pathogens.
Diseases Affecting Organ Function
The frequency and severity of diseases include circulatory diseases, denominated as heart or vessel diseases, depending on whether they affect the heart or blood vessels. Other diseases affect the respiratory tract, such as asthma or chronic bronchitis.
Cancer
Cancer occurs when certain cells, for reasons still unknown, undergo a transformation that causes them to divide rapidly and uncontrollably. This produces a mass of abnormal cells called a tumor. If cell growth is limited, the tumor is benign. If, instead, the cells divide without limit and extend to other organisms, it is called a malignant tumor or cancer.
Deficiency Diseases
Deficiency diseases are caused by a poor diet lacking in certain nutrients. These include anemia and vitamin deficiencies.
Traumatic Diseases
Traumatic diseases are those caused by accidents, which can be domestic, work-related, traffic-related, etc.
Endocrine and Metabolic Diseases
Endocrine and metabolic diseases are caused by excessive or deficient secretion of a hormone. Examples: Diabetes or obesity.
Mental Illness and Behavioral Disorders
Mental illnesses and behavioral disorders are alterations in thinking, behavior, or emotions that cause physical and psychological changes, as well as difficulties with social integration.
Genetic Diseases
Genetic diseases are disorders caused by the genes of the person concerned. They originate from mutations, duplications, or loss of genetic material. They may be hereditary.
Key Terms in Epidemiology
Prevalence: The number of patients with a certain disease at a given time.
Incidence: New cases of a disease appearing in a population.
Reservoirs of infection: Sites where pathogens are present and from which they are transmitted to humans.
Virulence: The degree of pathogenicity.
Pathogenicity: The capacity of a pathogen to produce disease.
Infectivity: The ability of infectious agents to settle and multiply.
Contagiousness: The ability of an organism to spread.
Immunity and Inflammation
Immunity is the resistance of organisms against infections caused by pathogens or foreign substances. The immune response against an antigen is called the immune response. Immunity acquired throughout life is called adaptive immunity, while immunity present during pregnancy is called innate immunity.
Inflammation is the first defense mechanism that occurs when germs pass through the body’s barriers. First, liquids and substances are released from damaged tissue cells, and then blood flow and capillary permeability increase to facilitate the departure of phagocytes and their actions toward the source of infection.
Serum and Vaccines
Serum provides immediate but short-lived immunity that disappears when the administered antibodies are eliminated. A vaccine protects against subsequent infections due to the formation of memory cells.
Antibiotics are substances produced and secreted by microorganisms that stop the growth of bacteria in very small quantities.