Understanding Key Health and Environmental Factors

Posted on Jan 26, 2025 in Geology

What is a Risk Factor?

Risk factors are those that provoke, facilitate, or predispose a person to contract a certain disease, by being exposed to certain causal agents. For example, smoking or working in a mine, where smoke and dust minerals can cause respiratory diseases.

Types of Abiotic Contaminants

  • Primary (identifiable): Particles, sulfur compounds, nitrogen compounds, inorganic carbon compounds, CO2 (hydrocarbons), and radioactive compounds.
  • Secondary: The way the atmosphere and physicochemical-chemical interactions work.
    • Photochemical smog (cars, industry)
    • Acid smog (acid rain)
    • Excess ozone (worsens chronic respiratory diseases)

Foodborne Illnesses

More than 250 different diseases are described:

  • Most are infectious, caused by different bacteria, viruses, and parasites (toxoplasmosis and salmonella).
  • Others are poisonings caused by toxins or chemical products that have contaminated the food, such as fungi.

Infant Mortality Rate

The infant mortality rate indicates the probable death of a subject during the first year of life. The calculation uses the following formula: IMR = No. of deaths under 1 year x 1,000 / Total number of births.

Difference Between Continuous and Discrete Variables

A continuous variable, unlike a discrete one, can never be measured exactly; there must inevitably be an error of measurement. Continuous variables are always recorded discreetly, the magnitude of the distance between adjacent recordable values being determined by the accuracy of the measurement.

Variables

Patterns of occurrence: These are used to see how a disease is distributed within a population. Three modes of occurrence are studied: time (when), person (how), and place.

  1. Person Variables:

    • Inherent factors: (immune)
    • Internal: Age, sex, race, ethnic background.
    • External: Level of studies, income, and civil state.

  2. Place Variables:

    • Administrative place (country, region, locality)
    • Epidemiological place

  3. Time Variable: To see the time in the case of an event.

Epidemiology of Infectious Diseases

The study of infectious diseases is a global phenomenon that affects large masses of the population.

Uses of Epidemiology:

  • Study of the evolution of morbidity and mortality caused by these diseases and the affected groups. It allows for the design of strategies for their control, elimination, and eradication.
  • In the hospital context, it is used to investigate the etiology, transmission, and mechanisms of the factors involved. It allows for the definition of programs and actions for surveillance, prevention, and control.
  • It is useful for analyzing the causes of the emergence of new pathogens.

Infectious diseases cause 25% of deaths in the global population. They are the second leading cause of death in the general population and the leading cause overall in childhood and youth.

Achievements:

  • Eradication of smallpox.
  • Control of polio, guinea worm, leprosy, and neonatal tetanus.
  • Decrease in mortality, morbidity, and disabilities due to infectious diseases.

Basics:

  • Colonization: Proliferation of an infectious agent in the host.
  • Infection: The invasion into host tissues.
  • Infectious disease: Clinical manifestations produced by the infection.
  • Epidemiological chain: The process of transmission from a reservoir to a susceptible host.

Disease Agent:

  • Infectivity: Characteristic of the infectious agent that implies the capacity to enter, survive, and replicate in the host.
  • Pathogenicity: Capacity to produce disease in the infected population.
  • Virulence
  • Antigenic or immunogenic ability

Environment:

  • Reservoir: The host where the agent’s survival is good under natural conditions.
  • Source of infection: The occasional habitat where the agent remains and has the capacity to reproduce.

Transmission Mechanisms:

  • Direct contact:

    • Sexual contact
    • Mucous contact
    • Transplacental
    • By the bite of an animal
    • By hands
    • By an aerosol of large and medium droplets produced by coughing or speaking

  • Indirect contact:

    • By air
    • By inanimate vehicles (water and/or food, blood, earth)
    • By vectors (a superior animal that transports the agent from one host to another)