One Health Approach: Human Health and Environment

Types of Pathogens

• Viruses: smaller than bacteria, invade cells, take over genetic machinery, and duplicate themselves (e.g., AIDS, Flu)
• Bacteria: larger in size, contain different organelles, have metabolic functions, can self-reproduce, and survive on their own (e.g., Tuberculosis, UTI)
• Parasites: can be roundworms, head lice, or protozoa (unicellular organisms)
• Fungi: can be zoonotic (transmissible from animals to humans)

Infectious Diseases

• Defined as when a pathogen invades the body and multiplies in its cells and tissues
• Examples: Tuberculosis, flu, malaria
• Contagious illnesses are caused by germs
• Direct contact: body fluids, blood transfusion, droplets
• Via vectors: living organisms that carry certain types of disease/pathogen (e.g., Dengue disease)
• Vehicle: non-living organisms that transport a pathogen from one person to another (e.g., food vectors transmit Hepa B and C, raw meat, airborne)

Antibiotics and Self-Medication

• Antibiotics should only be prescribed by a doctor
• Do not self-medicate, as it can lead to:
  • Wrong self-diagnosis
  • Adverse reactions
  • Incorrect dosage
  • Anti-microbial/biotic resistance

Anti-Microbial/Biotic Resistance

• Occurs when germs develop the ability to defeat the drugs designed to kill them
• Happens naturally due to germ evolution, but can be sped up by irresponsible use of drugs
• Affects both viruses and bacteria

Ecology and Biodiversity

• Levels of ecology:
  • Biosphere: living and non-living organisms in the entire earth
  • Biomes: particular areas with specific climate or vegetation (e.g., marine, tundra, grasslands, desert, forest)
  • Ecosystem: portion of biome, interactions between living and non-living organisms
  • Community: either/or non-living or living organisms
  • Population: one specific organism in a particular area
  • Organism/individual: one particular organism
• Why biodiversity occurs:
  • Natural selection
  • Genetic drift
  • Mutation
• Levels of biodiversity:
  • Ecosystem diversity: pertains to a variety of habitats, communities, and ecological processes

One Health Approach

• Program initiated in 2004 by the World Health Organization
• Connects the health of people, animals, and the environment
• Goal: design and implement programs, policies, legislation, and research to achieve better public health outcomes
• Main organizations: World Health Organization, Food and Agriculture, World Health Organization for Animal Health, and United Nations Environment Programme

Human Health and Well-being

• Defined as a state of complete physical, mental, and social well-being
• Not just the absence of disease or infirmity
• In a state of balance and equilibrium
• Physically healthy: no malfunctions, no pain, and able to perform physical activities
• Mentally healthy: not anxious, able to cope with challenges
• Factors that can affect well-being: injury, disease, death, economic loss, or damage

General Categories of Hazards

• Chemical hazards: toxic chemicals in the environment (e.g., asbestos, heavy metals, formalin, plastics)
• Natural hazards: naturally occurring, cannot be controlled (e.g., fire, earthquake, typhoon)
• Cultural hazards: hazards ingrained in societal norms (e.g., female genital mutilation, child marriage, Western diets)
• Lifestyle hazards: bad habits (e.g., smoking, unsafe sex, excessive drinking)
• Biological hazards: can infect humans, particularly if organisms are pathogenic (e.g., germs, 1,400 pathogens that can infect humans)

Test your knowledge on the One Health Approach, a program initiated by the World Health Organization in 2004. This quiz covers the interconnectedness of human health, animals, and the environment, and how organizations work together to achieve better public health outcomes.