Term
|
Definition
Transmission by an inanimate reservoir(food, water, air)
Vehicles that bring bacteria into body |
|
|
Term
|
Definition
Anthropods, especially fleas, ticks, and mosquitoes(which all inject bacteria into your bloodstream and take a blood meal from you)
Transmit disease by two general methods:
-Mechanical transmission: arthropod carries pathogen on feet(flies can carry 100's of thousands of microbeson each foot(6 feet= millions of microbes per fly)
-Biological transmission: pathogens reproducesin vector |
|
|
Term
|
Definition
Are aquired as a result of a hospital stay
Affect 5-15% of all hospital patients
Terrible organisms
Antibiotic resistant infections
The chain of disease path sometimes leads back to physicians and nurses-not washing their hands
Hospitals have committees that constantly watch all patients and look for sudden fever in patients. They are watching for sudden outbreaks. Made up of infection control physician, and nurse, laboratory worker, and pharmacist |
|
|
Term
|
Definition
VRE=vancomycin resistant enterococcus
Staph picks up the same mechanism as VRE and makes MRSA resistant to vancomycin(VRSA) |
|
|
Term
|
Definition
USA100: 92% of health care strains-hospital strain(HA-MRSA stands for hospital acquired MRSA) very resistant
Vancomycin is the only thing that will treat this and sometimes it won't.
USA300: 89% of community-acquired strains. It is not antibiotic resistant, but it is extremely invasive
2004 the football team got turf burns-got infected, looked like spider bites all around it. Gave them steroids, bad thing. Within 36 hours, it was in bone, had to have surgery. |
|
|
Term
| Emerging infectious diseases |
|
Definition
Diseases that are new, increasing in incidence, or showing a potential to increase in the near future
Either brand new microbes, or microbes that have never infected humans before.
U.S. Government helped birth this, 15 years ago they sat aside $$ for research
Tuberculosis= re-emerging disease, it has been around for 1000's of years, got it down to where only 100's of cases known, but now it is back on the rise |
|
|
Term
| Emerging infectious diseaes: Contributing factors |
|
Definition
Genetic recombination(picks up bad habits from other organisms)
-E. coli0157, avian influenza(H5N1)
E. coli0157 is a true pathogen, not normal flora. It picked up it's bad habits from shigella-causes erosion of lining of gut-causes (HUS)Hemolytic-uremic syndrome-bleeding of kidney, distroys kidney
Evolution of new strains-change over time-mutation, random
-V. Cholerae0139 AKA. el tor(the terrible)
Inappropriate use of antibiotics and pesticides
-Antibiotic-resistant strains=MRSA
Change in weather patterns
-Hantavirus-infects small rodents, causes hemoragic fever similar to ebola. When dry weather happens, it becomes airborne, rodent gets it, excreted in urine and feces. If you breath it in, you can get it. Renevated houses that had rodent problems can be a way to contract it. Can cause bleeding of lungs and eyes too. |
|
|
Term
Emerging infectious diseases
Continued |
|
Definition
Modern transportation- makes the job of a physician harder, they have to be able to diagnose any disease in the world at any time right here in Terre Haute Indiana
-West Nile Virus
Ecological disaster, war, and expanding human settlement
-Coccidiodomycosis- infects the lungs, AKA valley fever
Animal control measures
-Lyme disease- 1976ish first incidence was in Lyme Connetticut. Bad rash, shaped like a bullseye with the deer tick in the middle(only 75% get this rash, the other 25% have a hard time diagnosing this)
Public health failure- didn't know about giving booster shots
-Diphtheria |
|
|
Term
|
Definition
The study of where and when disease occur
Center for disease control and prevention(CDC)
-Collects and analyzes epidemiological info in the USA
-Publishes Morbidity and Mortality Weekly Report(MMWR)
-Journal of Emerging Infections
Descriptive: collection and analysis of data(Snow)
Analytical: comparison of a diseased group and a healthy group(Nightingale)
Experimental:controlled experiments(Semmelweis)
Case reporting:health care workers report specific diseases to local, state, and national offices
Nationally notifiable diseases:physicians are required to report occurrence(STD's, chicken pox, chollera) |
|
|
Term
|
Definition
Father of epidemiology
1848-1849
Mapped the occurrence of choleral in London, traced it back to a certain well, closed off the well, people stopped contracting cholera |
|
|
Term
|
Definition
| 1846-1848 Showed that handwashing decreases the incidence of puerperal fever(child birth fever) |
|
|
Term
|
Definition
1858
Showed that improved sanitation decreases the incidence of epidemic typhus |
|
|
Term
|
Definition
| Incidence of a specific notifiable disease-sickness |
|
|
Term
|
Definition
| Deaths from notifiable diseases-death |
|
|
Term
|
Definition
| Number of people affected in relation to the total population in a given time period |
|
|
Term
|
Definition
| Number of deaths from a disease in relation to the population in a given time |
|
|
Term
|
Definition
The ability to cause disease
Features that allow it to get in the body and set up disease |
|
|
Term
|
Definition
The extent of pathogenicity
Toxicity-how toxic it is.
Flagellum is a virulence-if you mutate to make bacteria without the flagellum, it won't be able to set up disease |
|
|
Term
|
Definition
Mucous membranes-respiratory-most common route by far
Skin-1st line of defense-bacteria, as far as we know, can't invade intact skin. Virus and fungi can infect intact skin
Parenteral route-breaks in skin(wounds, cuts, scrapes, hang nails_
All have a prefered method of entry |
|
|
Term
| Numbers of invading microbes |
|
Definition
ID50: infectious dose for 50% of the test population. Non lethal dose, 1/2 get infected, 1/2 don't get infected
LD50: Lethal dose(certain number of a toxin) for 50% of the test population. Population of animals are given lethal dose 50% die, the other 50% overcome with their immune system
This process figures out which pathogen is the worst. |
|
|
Term
| Bacillus anthracis(anthrax) |
|
Definition
Skin-ID50=10-50 endospores. Very susceptible, best route
Inhalation-ID50=10,000-20,000 endospores
Ingestion-ID50=250,000-1,000,000 endospores. This tells us that acid in stomach is bad news for endospores |
|
|
Term
|
Definition
Botulinum-LD50=0.03ng/kg(most potent bacteria on earth
Shiga toxin-LD50=250ng/kg
Staphlyococcal enterotoxin(food poisoning) 1350ng/kg |
|
|
Term
|
Definition
Adhesins/ligands bind to receptors on host cells
-Glycocalyx(slime capsule):Streptococcus mutans(causes cavities, acid from fermentation destroys enamel)
-Fimbriae:E. coli- sticks to the intestine cell(wants to be in the colon)
-M protein: Streptococcus pyogenes. M proteins allow this to stick to throat cells only, if not, it dies in the stomach
Form biofilms |
|
|
Term
|
Definition
Prevent phagocytosis-pathogenic mechanism
-Steptococcus pneumoniae-first organism that was mutated to not form a capsule, it couldn't set up disease
-Haemophilus influenzae
-Bacillus anthracis |
|
|
Term
|
Definition
M protein(adhesion protein)resists phagocytosis
-Streptococcus pyogenes
Opa protein- inhibits T helper cells- inhibits your natural immunity
-Neisseria gonorrhoeae
Mycolic acid(waxy lipid) resists digestion
-Mycobacterium tuberculosis-best bacteria out there, can't get rid of it once you get it. Water proof bacteria |
|
|
Term
|
Definition
| Coagulates fibrinogen-can coagulate our blood-ascepticemia |
|
|
Term
|
Definition
Digest fibrin clots
Opposite of coagulase
Staph can use both kinase and coagulase
Pull kinases mechanism out of bacteria and use them to digest clots if someone is having a heart attack |
|
|
Term
|
Definition
|
|
Term
|
Definition
Destroy IgA antibodies
Secretory antibodies |
|
|
Term
| Penetration into the host cell cytoskeleton |
|
Definition
Invasins-get into cell
-Salmonella alters host actin to enter a host cell
Use actin to move from one cell to the next
-Listeria
Certain bacteria can go INTO our cells just like viruses do.
They trick the cell into engulfing them. This causes cell to "ruffle" the membrane only when bacteria enters cell
Salmonella can cause asepticemia, they are headed to the blood stream |
|
|
Term
| Common causes of nosocomial infections |
|
Definition
Coagulase-negative staphylococci(lives all over our skin)15% of total infections, 89% resistant to antibiotics
S. aureus 15% of total infections, 80% resistant to antibiotics
Enterococcus(in intestines) 10% of total infections, 4-71% resistant to antibiotics
Gram-negative rods 15-25% of total infections, 3-32% resistant to antibiotics
C. difficile 13% of total infections, Not reported on resistant to antibiotics
C. difficile(pseudomembranous encephalitus) caused by clendomyosin wiping out enough of the normal flora in gut that C. difficile grows. Watch for bloody stool and diarrhea. Bad in elderly, sometimes they will have to have a fecal transplant in order for normal flora to come back, it works. |
|
|
