47 terms

Microbiology Final Dr. Walker

general information about S. aureus
Gram-positive, coccus shaped, facultative anaerobe, Greek name "bunch of grapes", halotolerant
habitat for S. aureus
normal flora of the skin, found also on fomites, normal flora on animals, found growing in dairy such as cheese and milk
S. aureus as a pathogen
opportunistic pathogen, most commonly associated with skin infections ofter nosocomial
caused by S. aureus and infects the heart valve
caused by S. aureus and infects the bones and joints
brain abscesses
caused by S. aureus and infects the brain
caused by S. aureus and infects the lungs
food poisoning
can be caused by S. aureus and can come from dairy
S. aureus has become resistant to methicillin, often found in health care facilities because many carry MRSA, transmitted by touch, sharing razors, towels and other personal items
S. caprae
destroys tissue around bones and joints, esp. after a fracture
S. saprophyticus
common cuase of urinary tract infections
S. epidermidis
common nosocomial infections and found on medical devices
general information about Campylobacter jejuni
gram-negative, helical cork-screw shaped, enteric pathogen, motile via flagella, microaerophilic,can grow in a variety of temperatures
habitat of C. jejuni
on warm-blooded animals, pathogenic to humans, spread through oral fecal route, can survive in the stomach so reaches large intestine can live in water, poultry is the most common source of infection to humans
virulence factors S. aureus
toxins make holes in the host cells- can survive high heat and food processing, proteases that break down collagen and other host tissue proteins, can form biofilms on medical devices such as IV's and catheters
C. jejuni as a pathogen
what is the importance of the cork screw shape, motile, cytholethal distending toxin causes severe diarrhea, less than 500 cells needed for symptoms to appear, causes typical GI symptoms, endotoxins can survive high heat
prevention and treatment of C. jejuni
hand-washing,thoroughly cooking food to reduce exposure, washing vegetables, antibiotics and hospitalization, acute infection, replacing electrolytes
complication with C. jejuni
neurological disorder (paralysis) Guillain-Barre syndrome
helicobactor pylori
same genus as C. jejuni, survives in the human stomach; causes ulcers; similar corkscrew shape, also gram-negative
salmonella and shigella
same genus as C. jejuni and also causes food poisoning and similar symptoms; also gram-negative and motile
general information of human papillomavirus
double-stranded DNA virus, non-enveloped, icosahedral shape, over 100 strands, all viruses are obligate intracellular parasites, commonly grouped as low or high risk depending on strain's potential cause of cancer, papilloma virus?,slow infection
habitat of HPV
no animal host, normal flora in humans, can infect any part of skin, colonize the respiratory and genital tracts
HPV transmission
can be transmitted by skin to skin, mother to child during birth, sexually transmitted
HPV-6, 11
low risk HPV, common cause of genital warts, also called condylomas, not associated with cancer, affect men and women, can be passed from mother to child, sexually transmitted
high risk, commonly associated with multiple types of cancer, responsible for 70% of all cervical cancers in women, can affect men also, most commonly transmitted sexually
prevention and treatment
regular screening for cervical cancers, minimize number of sexual partners, carriers may not know they are infected, gardisil vaccine, prescription cream for warts or crysurgery to remove warts,
gardisil vaccine
vaccine used to protect against HPV, NOT a treatment, effective against HPV 6,11,16,18 only , approved for men adn women ages 9-26(why not older?), optional, doesnt treat warts or cancer
general information of Mycobacterium tuberculosis
gram positve,bacillus, mycolic acid in cell wall, obligate aerobe, non-motile very slow generation time, most common in humans but can survive in the air
mycolic acid
virulence factor of M. Tb and prevents many stains from adhering to bacteria, forms an extra layer of lipids that protects the bacteria, gives the bacterium its name
causes Tb
infection in the lungs, spread by inhalation to respiratory tract, chronic or latent infection (symptoms are pressent in active infection), leading cause of death
virulence factors of Tb
capsule, which attaches to host/ avoiding the immune system. slow generation time, which can grow w/o triggering immune system immediately, mycolic acid, tubercles, which are structures that fform in the ungs during the latent form of the infection, made of living bacteria and mycolic acids, can convert to the active form
prevention and treatment of Tb
sanitation, screening healthcare workers and as asymptomatic carriers, tuberculin skin test, BCG vaccine, antibiotics that target mycolic acid
Tb skin test
only tests if youre exposed, NOT if youre sick, redness indicates immune reaction to TB protein, chest x-ray mest confirm a positive skin test
BCG vaccine
safe vaccine but not effective if you are a carrier, can cause false-positive skin test, developed from M. bovis
antibiotics for Tb
targets mycolic acids ( why?), TB is becomg drug-resistant
M. bovis
source of BCG, causes Tb in cows, may have been origin of M. Tb when was transferred to humans via unpasteurized milk
M. leprae
causes leprosy in humans
general information in Clostridium botulinum
gram positive bacillus, obligate anaerobe, forms endospores, motile, primary pathogen in humans,
habitats for C. botulinum
mainly found in soil, GI tract of many animals, such as fish and livestock, spores can be airborne and contaminate vegatables
C. botulinum virulence factors
endospore; neurotoxins, which causes paralysis and many neurological symptoms, exotoxins(protein), can travel through the body, blocks acetylcholine, which prevents neurons from communicatien with muscle cells, leading to paralysis
food borne botulism
often found in canned food or unpasteurized foods like honey and syrups, causes GI symptoms and leads to paralysis, infants are especially susceptible because of weak immune system, endospores are important for survival in foods,
wound botulism
spores enter a wound and travel throughout the bloodstream, no GI symptoms, only neurological
prevention and treatment
anti-toxin?, no vaccine, antibiotics arent effective, early diagnosis are key, infants can receive antitoxin
usefulness of C. botulinum
possible bioweapon because the neurotoxin is very potent and endospores make it easy to spread the bacteria; botox, the toxins paralyze muscles leading to wrinkle relaxation, can be used for muscle spasm disorder like hyperhidrosis and lazy eye
C. perfringens
causes gas gangrene; part of normal flora; problem in wound infections
C. tetani
causes tetanus; powerful neurotoxins; fatal
C. dificile
GI symptoms; normal flora; often causes problems when antibiotic treatment kills other normal flora, allowing C. dificile to become dominant and cause diarrhea