Vocabulary Pt 1
What is epidemiology?
The study of disease patterns in populations
Which Immune system is the first line of defense, aka physical barriers, antimicrobial substances and normal microbiota part of?
Innate Immune System
A disease that can be spread from an infected animal or person to another animal or person is refered to as what?
Communicable disease
The second line of defense is made up of what two things?
Immune cells and Active responses
Which scientist was the first to observe WBC in action?
Metchnikoff
What is the difference between incidence and prevalence?
Incidence - refers to the number of new cases in a specific time
Prevalence - refers to the total number of cases at any one time
What is the purpose of the physical barriers in the innate immune system? What is an example of a physical barrier?
Designed to keep microbes out or keep them from getting in
Ex. Skin being dry, oily, salty prevents growth; Mucous membranes trapping microbes; Stomach acidity denaturing molecules; mechanical mechanisms to clear and clean out passageways
What is the difference between symptoms and signs?
Symptoms - subjective effects experienced by patients, more qualitative
Signs - objective evidence measured by a healthcare worker, more quantitative
What are the 4 active responses in the second line of defense?
Phagocytosis, inflammation, complment and fever
What is the purpose of the first line of defense in the innate immune system
Deigned to keep foreign microbes from attaching to or entering the body
What is the difference between infection and colonization?
Infection - refers to a pathogen multiplying on/in the body
Colonization - refers to microbes multiplying on/in the body
What are the three parts of the first line of defense?
Physical barriers, antimicrobial substances and normal microbiota
A disease that has spread through the whole body is called what?
Systemic infections/diseases
What are three types of cytokines we talked about in class?
Chemokines, tumor necrosis factor, interferons
What does the second line of defense in the innate immune system deal with?
With foreign microbes once they are in or on the body
If an illness is labeled as latent, what does that mean? (explain the duration)
1) Incubation period (the time between initial exposure to a susceptible host and onset of illness), illness, convalescence (time of recovery and recuperation from the disease), latency (a period in which the individual is asymptotic, infectious agent is present but not active), recurrence (the disease happens again)
What are the 4 antimicrobial substances that we talked about in class and what do they do?
-Lysozyme: degrades peptidoglycan
-Peroxidase: generates ROS molecules from H2O2
-Iron-binding proteins: Lactoferrin, Transferrin, binds to iron, important in ETC
-Defensins: Short antimicrobial peptides that form pores in bacterial membranes
What are the 4 reservoirs of infection?
Water/soil/air
Human carriers
Animals
Hospitals
Name and give one characteristic about each of the 6 innate system immune cells
Neutrophils: most abundant in circulation, highest phagocytic activity
Monocytes: 2nd most abundant, differentiates into macrophages and dendritic cells
Macrophages: main function phagocytosis but are less powerful than neutrophils, limited role in antigen presentation
Dendritic cells: antigen presentation
Eosinophils: involved in destroying parasitic worms or large eukaryotic pathogens
Basophils: releases histamine used in allergic responses
In the complement system using complement proteins, what are the three outcomes?
-enhancing attachment for phagocytic WBC
Help initiate inflammatory response
Forms pores in bacterial cell membranes to induce cell lysis
A mosquito that is born with malaria, lands on you, bites you, and transfers malaria to you. What type of vector is this?
Biological
How do normal microbiota protect humans?
If the person behind has a cold and sneezes, what type of transmission is this?
Droplet transmission
Explain Phagocytosis
1) A bacterial cell is recognized by a phagocytic WBC and is engulfed and forms the phagosome
2)Lysosomes, which are an organelle, fuses with the phagosome to form the phagolysosome. The Lysosome then uses hydrolytic enzymes, or ROS or an acidic environment to destroy the bacteria cell
What is the difference between an epidemic and a pandemic?
Epidemic - occurs when an unusually large number of cases occur in a short period and or in a small area
Pandemic - an epidemic that has spread worldwide