Human Interactions with Microbes Flashcards
Exam 3
Infection
microbes enter the body through portals and start to multiply
Disease
microbes spread to tissues and organs
Carrier State
- human may be carrying microbes but may not be exhibiting signs and symptoms
- microbes are established but disease is not apparent
What is it called when disease starts to cause permanent damage to tissues and organs?
sequelae
Mortality
when people die from infection
Morbidity
when people survive infection
Mortality Rate
How many people are dying within a specific time range
Morbidity Rate
Out of X number of people infected, how many have survived
Epidemiology
the study of how often and severity of disease occurances in populations
What is the name of the federal agency responsible for keeping account of the spread of infections and diseases in our communities?
Where is the headquarters?
Center for Disease Control (CDC) & Prevention
Atlanta, GA
Portals of Entry (5)
Which is portal most used?
Non-Inclusive
- Mouth
- Skin
- Nostrils (most frequented)
- Eye
- Ear
- Anything with holes for entry
Portals of Exit (4)
Non-inclusive
- Anal
- Mouth (saliva)
- Nostrils
- Blood
Microbiota
- Non-pathogenic microbes that naturally inhabit the human body
- AKA normal flora
- Can change from non-pathogenic to pathogenic when immune system is compromised (enodgenous infection)
Endogenous Infections
- Infections caused by bacteria that are already within our body
- when normal, sterile/non-pathogenic flora becomes infected/pathogenic
Provide an example of endogenous infection
- We all have HSV1 (non-pathogenic)
- when we are stressed, they multiply and we grow blisters and cold sores from HSV1 (pathogenic)
What are the 2 types microbes that Microbiota are composed of?
- Microflora (plant-like)
- Microfauna (animal-like)
What is an example of Microflora?
fungal infection between our toes
Probiotics
good microbes we encapsulate to take as supplements to increase the level of good bacteria in our body to help fight off the bad bacteria
Prebiotics
food that helps the good bacteria to grow
Exogenous Infection
when the bacteria comes from outside the body
Microbiome
totality of all genetic materials
What are the 2 types of pathogens?
Provide definitions
- True: microbe that will cause infection in healthy individual
- Opportunistic: microbe that will cause infection when the immune system is compromised
How many lines of defense are there?
3
What is required for microbes to cause infection?
they have to make contact with cells
What are some structures that make up the 1st line of defense? (6)
- skin
- mucous membranes
- mucosal cells
- hairs on nostrils that trap microbes as we breathe in air
- hairs of eyelashes
- chemical in saliva (lysosomes that will kill most of the bacteria)
What makes up the 2nd line of defense?(7)
- lymphocytes (neutrophils, basophils, mast cells, NK Cells)
- fever
- inflammation
- anti microbial peptides
- iron binding proteins
- complement system
- interferon
What makes up the 3rd line of defense?
Immune cells that target specific antigens (T and B cells)
Innate Immunity
babies develop resistance to microbes in the environment
Signs
- observable by the observer (objective)
- ex: rash
Symptoms
- Felt by the patient (subjective)
- ex: You can’t see someone has a stomach ache. Can only go by what patient states
Subclinical
asymptomatic (no signs or symptoms)
Infectious Dose
- minimum number of microbes required to initiate an infection
- the lower the infectious dose, the more infectious/pathogenic the organism is
What are the 4 stages of clinical infection?
- Incubation
- Prodromal
- Invasion
- Convalescent
Incubation
- 1st stage of clinical infection
- initial entry of microbe into body
- no multiplication yet, may be no initial signs or symptoms
Prodromal
- 2nd stage of clinical infection
- microbes slightly start to multiply
- still no infection
- patient may have vague feeling of fatigue and the disesae incoming
Invasion
- 3rd stage of clinical infection
-Infection has occured - signs and symptoms are apparent
- Once infected, pateint my undergo mortility (death) or morbidity (survivial)
Convalescent
- 4th stage of clinical infection
- Stage reached if patient survivied infection (morbidity)
- microbes and symptoms decrease
What are the microbe-free areas of the body?
- Everywhere except the large-intestine (colon)
- If there are microbes elsewhere, sign of infection
What are the Patterns/Types of Infections? (9)
- localized
- systemic
- focal
- mixed/poly-microbial
- primary
- secondary
- super
- acute
- chronic
Localized Infection
infection is confined to a specific tissue or organ
Systemic Infection
infection is carried by bodily system (ususally circulatory) to infect entire body
Focal Infection
When microbe infects a tissue or organ, it breaks loose to infect another tissue or organ
Mixed/Poly-microbial Infection
infection caused by more than one species of microbe
Primary Infection
first time the microbe enters the body
Secondary Infection
- when a different type of microbe infects the body in a different tissue
- ex: infection in ankle, then different microbe comes and infects the wrist
Super Infection
- infection develops after the administration of a drug
- ex: take broad-spectrum drug that kills good bacteria
Acute Infection
- when the infection comes rapidly
- usually severe (may kill a bunch) but very short lived
Chronic Infection
infection carries over a long period of time (persists)
Parasite
- derives its nutritional need from host
- can be harmful or nonharmful
What are nosocomial infections?
AKA?
- infections aquired during hospital stay
- now called HAI (Healthcare Associated Infection)
Drug Susceptibility Testing
AKA?
- test that informs physician which drug to prescribe
- AKA Kirby Bauer
How are antibiotics produced?
- Naturally secreted chemicals by microbes to inhibity or destroy other microbes
