Introduction Flashcards
Why do we have an immune system?
To protect us from microogranisms with the potential to cause infectious disease, called pathogenic microorganisms or PATHOGENS
Types of pathogens
- Bacteria
- Virus
- Parasite
- Fungi
What type of pathogen most seriously infects humans?
Bacteria
What type of pathogen is least common in human infections?
Parastic protozoa
When does disease occur?
When we are unable to mount an effective immune response against a pathogen
Why do pathogens spread so quickly?
They are able to reproduce quickly and thus evolve quickly
What is the leading cause of death worldwide?
Infectious Disease
Why do we see an increase in life expectancy in canada over the last century?
Growing technology in controlling infectious diseases
What are the three possible outcomes when infected by a pathogen?
- ) We kill the pathogen
- ) The pathogen kills us
- ) We spread the pathogen to others
What are the 6 steps in the Chain of Infection?
- ) Infectious Agent (Pathogen)
- ) Reservoir (Us)
- ) Portal of Exit
- ) Mode of Transmission
- ) Portal of Entry
- ) Susceptible Host
How can we prevent & control infectious disease in a reservoir?
- Control vectors & animal reservoirs.
- Purifying water
- Sewage disposal
- Proper cooking
- Disinfectants & antibiotics
Endemic
The expected (baseline) level of an infectious disease that is continuously present in a population within a geographic area
Epidemic
An increase in the number of new cases of a disease above what is normal expected in that population in that geographic area.
Pandemic
An epidemic that has spread over several countries or continents
What are the main immune components?
- Cells (tissue, white blood cells - leukocytes, phagocytes & lymphocytes)
- Soluble Molecules (cytokines, acute phase proteins, antibodies)
What is donor blood separated into?
Plasma, White Blood Cells + Platelets, and Red Blood Cells
What percentage of blood is composed of blood cells?
45%. The other 55% comprises of soluble molecules
Where are blood cells derived from?
Hematopoietic stem cell located in the bone marrow
What are the two developmental pathways for white blood cells?
- Myeloid Progenitor cell -> phagocytes
- Lymphoid Progenitor Cell -> Lymphocytes
What two immune systems comprise the entire immune system?
Innate + Adaptive
Innate Immune System
Natural & non specific
Adaptive Immune System
Acquired & Specific
What two components comprise of the Adaptive Immune System?
- Antibody-mediated (humoral)
- T-cell mediated
