Infection and Immune System Flashcards
Virulence
- capacity to cause severe disease
- how hard it is to treat an organsim
susceptibility
- how prone the host is to the infection
what are the two groups most susceptible to COVID-19
- people over the age of 60
- those with underlying medical conditions
opertunistic infection
Secondary infection
- occurs after the treatment of another infection
- EXAMPLE: yeast infection
Nosocomial Infection
Hospital Acquired Infection
Aerobic
- survives in an oxygen enviorment
Anaerobic
does not require oxygen
endotoxins
- also known as pyrogens
- cell wall released during cell death
- when treated; cant prevent the toxic effects; causes the inflammatory process to be activated gram negative
exotoxins
- secreted toxins
- elicit the production of antitoxins
- can produce a vaccine against them
how can you determine if a bacteria is gram + or -
gram stain
example of an exotoxin
diptheria
septicaemia / sepsis
- bacteria in the bloodstream causing generalized infection
- caused by gram negative bacteria
what are the 3 life threatening pathogens - “super bugs”
- Staphylococcus aureus
- Methicillin- resistant Staphylococcus aureus (MRSA)
- Vanomycin- resistant Enterococci (VRE)
S. Aureus
- adapted over time to become life threatening
- common in nasal passages and on skin
- becomes opportunistic
- has developed an enzyme that destroys penicillin
- some strains have developed into broad spectrum antibiotics (Methicillinlike antibiotics)
MRSA is spread through
- spread through contact (person to person)
VREis spread through
- spread through contact
H. pylori is resistant to
clarithromycin
Salmonellae is resistant to
flouroquinolone
Neisseria gonorrhoeae is resistant to
cephalosporins and flouroquinolone
What are the 6 steps in viral infection invasion
- attatchment
- penetration
- uncoating
- biosynthesis
- assembly
- release
attachment
virus attaches to epithelial cell
penetration
cell engulfs the virus
uncoating
- virus contents released into the cell
biosynthesis
RNA enter the nucleus of the cell
Assembly
new phage particles are assembled
Release
new viral particles are made and released
treatment of viral infections
- antiviral medications
- immune system
Fungal infection
- large, thick walled organism
- opportunistic
- treated with antifungal medications
what is the most common fungal infection
Candida albicans
- resides in the skin, GI tract, and vagina
how are fungal infections treated
antifungal medications
Parasitic infection
- transmitted through vectors
Tapeworm symptoms
nausea, waekness, loss of appetite, abdominal pain, diarrhea, dizziness, weight loss and inadequate absorption of nutrients, bloating
malaria symptoms
fever, chills, headaches, nausea and vomiting, muscle pain and fatigue
nonspecific resistance
innate immunity
specific resistance
aquired or adapted immunity
adaptive (aquired) immunity
- not present at birth
- created in response to a foreign substance
- active and passive
active immunity
natural or vaccination
passive immunity
maternal or artificial
Innate immunity
- physical and chemical (skin, mucous membranes, hair, cilia, urine, deification and vomiting, lysozyme, gastric juice, saliva, sebum, )
- non specific resistance (phagocytes, inflammation, fever)
Skin
A thick layer of dead cells in the epidermis provides a physical barrier to viruses, bacteria, and microbes. As the epidermis sheds, microbes are removed
Mucous membrane
produce mucus to trap microbes so they cannot spread to the rest of the body
Hair
filters microbes, dust, and pollutants from the air to prevent them from invading the body
– present in the nose and ears
Cilia
lines the upper respiratory tract and traps and propels inhaled debris to the throat so it can exit the body more quickly
Urine
flushes microbes out of the body via the urethers
Phagocytes
ingest and destroy microbes that pass into body tissues
Inflammation
localized response in the tissue that occurs when a tissues are damaged or in response to other stimuli
Fever
inhibits bacterial growth and increases the rate of tissue repair when an infection is presented in the body
- will start by increasing enzyme activity; if too high will diminish activity
what antibodies are found in breast milk
IgA and IgG
Lymphocytes
- specific wbc
- t cells and b cells
- responsible for aquired immunity
b cells
- produce antibodies
- immunoglobulins
- works against bacteria and viruses
T cells
- react directly with antigen on surface
- works against viruses and cancer cells