Exam 2: Week 9, Monday (Infectious Diseases, Viruses and Fungi) Flashcards
Definition of infection:
Process in which an organism establishes a parasitic relationship with the host
immune response
- What is it produced by?
- What does it do? (simple)
•- Produced by invasion and multiplication of an organism
- •Produces injury to the host due to toxins from microorganisms and tissue/cell death of host
Development of an infection depends on what three things?
- Transmission
- Proper environment
- Susceptibility of the host
Two outcomes of pathogen invasion:
- Colonization of organisms- microorganisms present in tissue but do not create systemic disease
- You will be a carrier and transmitter of disease but may not have signs and symptoms
- Clinically apparent infection- host injury with signs and symptoms
What is the significance of the fact that different types of organisms (I think she means pathogens) vary in shape, size, structure, growth requirments, and ability to stay alive? (2 main)
- Provides a basis for identification of organism (and therefore diagnosis)
- Allows for development of a treatment
Characteristics of Viruses (4)
- how many types?
- what are they made from?
- dependent or not dependent on host?
- pharma treatment?
•over 400 that infect humans,
made up of RNA or DNA nucleus covered in protein
dependent on host for replication
antivirals- interfere with illness limiting time necessary for healing
Characteristics of Mycoplasmas (3)
What are they?
dependent or not dependent on host?
pharma treatment?
•Mycoplasmas-
self replicating bacteria
require host,
sensitive to some antibiotics
Characteristics of Bacteria (3)
What are they?
dependent or not dependent on host?
pharma treatment?
•Bacteria-
single-cell microorganism of many variations -
- rod, spherical, spiral, gram positive/negative (staining), motility, tendency toward capsulation, capacity to form spores, aerobic, anaerobic;
do not require host,
specific antibiotic for type
Name 9 things Varieties of bacteria are based on:
- rod,
- spherical,
- spiral,
- gram positive/negative (staining),
- motility,
- tendency toward capsulation,
- capacity to form spores,
- aerobic,
- anaerobic
What are Rickettsiae?
•- animal pathogen that effects humans via insect bite (tick, flea)
What are Chlamydia (not the specific disease)?
pharma treatment?
•smaller than bacteria but larger than virus,
respond to some antibiotics
What are protozoa?
•single cell or loosely bound group of cells, parasites (round and flatworms)
what are fungi?
Alterate name?
example?
- yeasts or molds,
- called mycoses in humans -
- Example: athlete’s foot (medical name is Tinea pedis)
What is the term for fungi in humans?
mycoses (a disease caused by infection with a fungus, such as ringworm or thrush)
what is the medical term for Athlete’s Foot?
Tinea pedis
What are Prions?
examples
proteins without nucleic acid -
Nasty little things that are hard to treat
Examples:
- Creutzfeldt-Jakob Disease (humans) or
- mad cow disease (bovine
8 Infectious Organisms
- •Viruses- over 400 that infect humans, made up of RNA or DNA nucleus covered in protein, dependent on host for replication, antivirals- interfere with illness limiting time necessary for healing
- •Mycoplasmas- self replicating bacteria require host, sensitive to some antibiotics
- •Bacteria- do not require host, single-cell microorganism of many variations - rod, spherical, spiral, gram positive/negative (staining), motility, tendency toward capsulation, capacity to form spores, aerobic, anaerobic; specific antibiotic for type
- •Rickettsiae- animal pathogen effects humans via insect bite (tick, flea)
- •Chlamydia- smaller than bacteria but larger than virus, respond to some antibiotics
- •Protozoa- single cell or loosely bound group of cells, parasites (round and flatworms)
- •Fungi- yeasts or molds, called mycoses in humans - Tinea pedis (skin), athlete’s foot
- •Prions- proteins without nucleic acid - Creutzfeldt-Jakob Disease (humans) or mad cow disease (bovine)
How are viruses classified?
Classified by how they reproduce
Classified as replicating DNA or RNA
How do viruses interact with the body?
Virus invades the host cell, takes control of the cell’s metabolic function, and uses the cell’s synthesizing mechanisms to “crank out new viruses.”
What do viruses consist of, and why do I care?
•Viruses consist of genetic material and a protein shell (capsid) – no cellular components for reproduction, which is why it needs to take over a host cell
Explain the 4 steps of Viral Replication in the Host Cell
- •adsorption – virus attaches to host cell wall
- •penetration and uncoating – enters or fuses with cell wall, releasing its genetic material inside and removing any remaining viral coating
- •biosynthesis – takes control of cell’s synthesizing system (DNAor RNA)
- •maturation and release – mature virus genetic material and core cell released, sometimes killing host cell, but if not, host cell remains infected
(picture is an example of a virus taking over a bacterial host cell)
Blood borne Viral Pathogens: What are the three most common dangers to healthcare workers?
When are we at greatest risk?
- Hepatitis B (HBV)
- Hepatitis C (HCV)
- HIV (Human Immunodeficiency Virus)
Greatest risk during invasive procedures or digital palpation of sharps
What point did Dr. T make about using up extra protective equipment?
She never faults anybody for using up extra protective equipment. It is better to prevent infection than try to treat it after it has spread.
How many herpesivrus types are there?
8
List the 8 types of herpesviruses
- •Herpes simplex virus (HSV-1), Type 1, cold sores, visceral organs, mucocutaneous areas
- •Herpes simplex virus (HSV-2), Type 2, genital herpes
- •Type 3, varicella-zoster; chicken pox and shingles
- •Type 4, Epstein-Barr infectious mononucleosis virus (EBV)
- •Type 5,Cytomegalovirus (CMV)
- •Type 6, Roseola human herpes virus (HHV)
- •Type 7, Herpes serologically associated with roseola (HHV)
- •Type 8, Human herpes associated with Kaposi’s sarcoma (HHV)
HSV-1 stands for:
Causes:
Herpes simplex virus, type 1
Causes: Cold sores, visceral organs, mucocutaneous areas
Can cause pneumonia - cold sores in the lungs (terrible to treat)
What is the biggest category of viruses we will see?
Herpes viruses
What does HSV-2 stand for?
Example
Herpes Simplex Virus, type 2
genetal herpes
2 examples of herpes virus type 3 (common name, medical name)
Chicken Pox (Herpes Varicella)
Shingles (Herpes Zoster)
What does EBV stand for?
exmaple
Epstein-Barr virus (herpes type 4)
Mononucleosis virus
What does CMV stand for?
Cytomegalovirus (Herpes Type 5)
What does HHV stand for?
Roseola Human Herpes virus (herpes type 6)
What virus is serologically associated with roseola?
type 7
What virus is associated with Kaposi’s sarcoma?
Herpes type 8
Also a human herpes virus
What are the three Human Herpes Viruses?
- Type 6, Roseola human herpes virus (HHV)
- Type 7, Herpes serologically associated with roseola (HHV)
- Type 8, Human herpes associated with Kaposi’s sarcoma (HHV)
Chicken Pox:
Transmission?
When is it contagious?
vaccine?
Anything else?
•Airborne transmission,
highly contagious from 1-2 days before onset until lesions crust over
now there is a vaccine (but it is new enough that many of us will not have recieved it)
Only get chicken pox once (then you are suceptible to Shingles)
Herpes Zoster
4 characteristics
2 possible symptoms
You are succeptible if you have had chicken pox (virus dormanat inside your nerve roots, reactivates to become Shingles)
Older people more susceptible
Now there is a vaccine, but only reccomended for older adults
Can be very painful (so much so that you do not want clothing touching you)
Symptoms:
- •Eruption follows dermatome
- •Post-herpetic neuralgia (PHN) may last throughout lifetime
- •Pain, hyperalgesia (increased pain from a painful stimulus), allodynia (painful reaction to a non-painful stimulus) – hyperalgesia and allodynia are common in true neuropathic pain
Roseola characteristics:
Symptoms
usual population
•Roseola –
Population: most common in children, age 6 mo – 3 years;
Symptoms: fever, rash,
(very scary looking butnot usually too serious)
Infectious Mononucleosis Symptoms (4 particularly distinctive in bold)
- Central
- fatigue
- malase
- loss of appetite
- headache
- Throat
- soreness
- Reddeining
- Respiratory: cough
- Systemic
- Chills
- Fever
- Aches
- Gastric: Nausea
-
Spleen
- enlargement
- abdominal pain
- Lymph nodes
- swelling
- Tonsils
- reddening
- swelling
- white patches
- Visual
- photophobia
Infectious Mononucleosis characteristics:
common population
cause
incubation time
complication risk
What other disease is it associated with?
Used to be called the kissing disease
Often spread in athletes because of sharing drinks, etc.
Caused by Epstein Barr virus (Herpes type 4)
- May incubate for 4-6 weeks
- Major complications rare, but splenic rupture is most common (Kehr’s sign)
- Association between infectious mononucleosis and subsequent development of multiple sclerosis (MS) – twice as likely – may be associated with immune response
Cytomegalovirus (CMV) details (5)
- •Common virus, common opportunistic infection in AIDS (check CD4 count)
- •Many people do not know they are infected because they show no symptoms
- •Once infected, body retains virus for life - usually remains dormant if you’re healthy
- •Active CMV: fever, pheumonia, diarrhea, ulcers in GI tract, hepatitis, encephalitis, behavioral changes, seizures, coma, visual changes or blindness
- •Spread through body fluids
- very transmissible
- some babies are born with it (see picture)
What is Kaposi’s Sarcoma? (3)
- Herpes virus type 8
- Highly associated with AIDS.
- Look sort of like big sores or moles but not quite (sort of like in between the two).
From Wikipedia: Kaposi sarcoma (/kəˈpoʊsiː sɑrˈkoʊmə/; KS) is a tumor caused by infection with human herpesvirus 8 (HHV8), also known as Kaposi sarcoma-associated herpesvirus (KSHV) or KS agent. The viral cause for this cancer was discovered in 1994. (https://en.wikipedia.org/wiki/Kaposi’s_sarcoma)