Clas #11 Flashcards
Define Virulence
The disease producing potential of a bacteria
Very virulent microorganisms are called…
pathogens
What is a saprophyte?
an environmental organism that feeds off of dead or decaying organic material, usually fungi.
*These are harmless to humans but can be opportunistic if host immune system is compromised
How do Prions affect their host organism?
They are abnormally shaped proteins that don’t actually replicate in a normal way–They attack other proteins, change their shape and make them into prions..Their propagation is unclear, so it is difficult to treat.
Prions can cause a neurodegenerative disease called…
Creutzfeldt-Jakob disease
How do viruses replicate?
Insert their genome (their own DNA) into the host cell DNA, then uses the cells energy to replicate.
*This is why viruses can’t replicate outside a living cell
Explain the physical structure of a virus
- small, no organized cellular structure
- protein coat surrounded by nucleic acid core
- some have lipoprotein envelope
How do latent viruses function?
Enter cell, insert genome, and remain dormant until stimulated
What is an example of a latent virus?
varicella-zoster, epstein-barr, herpes
What is an oncogenic virus?
a virus that can transform host cells to malignant cells during replication
- HPV
- Hep. B
- Epstein-barr
H1N1 and H3N2 are examples of what kind of virus?
influenza
What disease is caused by the retrovirus group?
HIV/AIDS
What kind of virus is caused by a single stranded RNA virus?
Enterovirus in mucus, saliva and stool, like poliomyelitis
What makes bacterial infections easier to treat than viral infections?
bacteria are a small, simple structure made up of a cytoplasm covered by a RIGID cell wall that is susceptible to anti-bacterial
Whats the difference between flagella and pilli on bacteria?
Flagella: arms that help propel the bacteria
Pilli: tiny microfilaments that help with adherence
How do these 3 different bacteria divide?
Streptococci..
Diplococci…
Staphylococci…
Strep: divide into chains
Dip: divide into pairs
Staph: divide into clusters
Define biofilm
structured community of bacteria
What are spores?
group of bacteria waiting for stimulation to replicate
What is the difference between aerobic bacteria and anaerobic bacteria?
aerobic require oxygen to replicate and anaerobic hate too much oxygen
What makes facultatively anaerobic bacteria more virulent than both aerobic and anaerobic?
these bacteria are more virulent because they have the ability to adapt and survive either with OR without oxygen
What colour are gram positive bacteria?
g+ are RED
What colour are gram negative bacteria?
g- are BLUE
What colour are acid-fast bacilli?
*TRICK! They don’t stain at all!
What are spirochets?
helical, long bacteria
These bacteria are smaller than normal bacteria that tend to be resistant to many antibiotics…
mycoplasms
Name two organisms that are known for having both viral and bacterial characteristics
- Rickettsiaceae
2. Chlamydiaceae
What is rickettsiaceae? How is it transmitted?
an organism with both viral and bacterial characteristics
-requires host nutrients AND cell ATP byproducts to replicate, carried by fleas, ticks and lice
What organism causes rocky mountain spotted fever and typhoid fever?
rickettsiaceae
What organism is known for causing ocular infections in newborns?
Chlamydiaceae
Why do fungal infections usually manifest ON the body surface rather than as internal infections?
they require a temperature less than normal body temperature
If your patient with a fungal infection was prescribed penicillin, would you as a nurse be concerned? Why or why not?
Yes, because fungal infections are often NOT susceptible to penicillin-like antibiotics d/t rigid cell wall
What is the difference between yeast infections and mold infections?
Yeast: waxy, creamy texture
Molds: cottony/powdery
Malaria and dysentery are examples of what kind of parasite?
Protozoa
How are protozoa parasites transmitted?
- host-host (sexual contact)
- Arthropod vector (lice, flea, ticks)
- contaminated food/water
Worm-like parasites are called….
helminths (roundworm, tapeworm, flukes)
How are helminths transmitted?
- ingestion of fertilized ova
- penetration through the skin by arthropod vector
What are arthropods? How are they transmitted?
live, disease carrying creatures
- Ticks, mosquitoes, flies, mites, scabies, lice, fleas
- clothing, bedding, combs/brushes
What is bubonic plague carried by?
Fleas and rats
If my child has lice, what disease might I be concerned about them acquiring?
epidemic typhus
What are 4 different portals of entry for infectious organisms?
- Penetration (primary, accidental, medical)
- Direct contact (secretions, mom-babe)
- Ingestion (must survive pH, enzymes, peristalsis and normal flora)
- Inhalation (must survive mucus, cilia, coughing, antibodies and phagocytes)
Why are ingested or inhaled infectious organisms considered “tough” when they cause illness?
Ingested organisms must survive the body’s pH, enzymes, peristalsis and normal flora before causing infection.
Inhaled organisms must survive mucus, cilia, coughing, antibodies and phagocytes before causing infection