Disease Flashcards
What is microbiota
certain bacteria living on a particular place on your body, should stay on the certain place or it can make you sick
What is resident microbiota
things that live there throughout life
What is transient microbiota
short stay microbes
When is the origin for microbiota
before birth, in the placenta
When does new mircobes get introduced
on the way out, i.e. vaginal tract, inhaling air when first starts to cry, people touching the baby
What is opportunistic microbe
a microbe that is normally harmless but can be pathogenic
How does an opportunistic microbe become pathogenic
Immunosuppression
Changes in biota: something that shouldn’t win does
Competition
Antibiotics, hormone changes, stress
-Introduction of normal biota to unusual site
Where do pathogens live before the infect you?
Animal reservoirs, human carriers, non-living reservoirs
Example of animal reservoirs
zoonosis: contact w/ animal or its waste, eating animal, bloodsucking arthropods
- Extensive Reservoirs
Why would pathogens in humans not normally affect animals? (life-cycle)
They are usually dead in host, meaning we don’t participate in the life cycle like animals do… animals don’t normally eat us
Examples of human carriers
asymptomatic, aids: may take years for disease to develop
Example of non-living reservoirs
Soil, water, food
Exposure ‘contaminated’: presence of microbes in/on the body, could become new resident of microbiota, be a transient, overcome defenses and multiply and become established (infection)
Modes of transmission
Contact, Vehicle, Vector
What is direct contact
handshaking, kissing, sexual intercourse, bites
What is indirect contact
drinking glasses, toothbrushes, toys, punctures
What is droplet transmission
from sneezing within one meter
What is airborne vehicle transmission
dust or droplets carried more than one meter
What is waterborne vehicle transmission
streams, swimming pools (fecal-oral contamination)
What is foodborne vehicle transmission
bodily fluids, poultry, meat, seafood
What are mechanical vector transmitters
on bodies of flies and roaches, accidental transmitters, not part of the life cycle
What are biological vector transmitters
transmits pathogen and multiples, part of life cycle
lice, mites, mosquitos, ticks
Portals of entry
Skin: cuts, burrows
Eyes, ear, mouth, nose, placenta, etc
Mucus membranes: warm, moist, hospitable. Respiratory tract most common entry site
What kind of entry is not true and give an example
Parenteral: not a true portal of entry, pathogens directly into tissue beneath skin on mucous membrane
Ex: a nail penetrating the foot causing tetanus
