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238 Cards in this Set
- Front
- Back
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Define commensalism. Give an example.
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One organisms benefits, and the other is not impacted.
microflora |
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Define mutualism. Give an example.
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Both organisms benefit.
e.coli in the gut |
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Define parasitism
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Microbe benefits at the expense of the host
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"True" or "primary" pathogens vs. Opportunistic pathogens
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True pathogens are linked to a disease when they are found. They cause disease in healthy persons
Opportunistic pathogens cause disease when the immune system is suppressed as opposed to infecting healthy persons ex. superinfections |
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What is the basis of Koch's Postulates?
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to act as a guide to link specific microbes to a specific disease
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List the events of Koch's Postulates
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-isolate potential pathogen from a diseased individual
-grow to pure culture in a lab -inoculate into experimental host and look for signs of disease -if disease is evident and if the potential pathogen can be re-isolated, it is the likely cause of disease |
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Events in the production of disease
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-contact and colonization
-infection (microbe establishes itself and evokes an immune response) -disease (normal physiology is altered) -virulence (the ability to cause disease) |
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Portals of Entry/Exit
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-skin (dead skin cells)
-GI tract (lumen) -respiratory -urogenital -placenta (for congenital disorders) (STORCH infections) |
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Transients
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microbes that occupy the body for only a short amount (as opposed to resident microbes)
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Microbial factors that affect virulence
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adherence
invasiveness toxins (endo vs. exotoxins) |
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Structures that support for adherence
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-capsules (slime)
-pilli and fimbriae -attachment proteins on viruses |
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Structures that support for invasiveness
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-enzymes (e.g collangenase, hyaluronidase, streptokinase)
-antiphagocytic factors (capsules) |
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List an example of an antiphagocytic factor
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leukocidin which are toxic to WBCs
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hyaluronidase
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spreading factor, in C.T
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streptokinase
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clot dissolving enzyme
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Endotoxin
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not secreted but is released after cell is damaged
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Exotoxin
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secreted by a living bacterial cell into the infected tissues
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Characteristics of Endotoxin
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-LPS
-from gram negative bacteria only -associated with cell wall of bacteria -poorly antigenic -heat stable -non-toxoidable |
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Toxoid
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neutralizes toxicity but still remains effective antigen for vaccines
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Characteristics of Exotoxin
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-protein
-from either gram negative or gram positive bacteria -secreted by cells -good antigens -heal liable (sensitive) -toxoidable |
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Endotoxin effects
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general, systemic effects: fever, edema, disseminated intravascular coagulation
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Exotoxin effects
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varied, often directed toward specific body systems: neurotoxins, entertoxins, etc
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Stages of Infections
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-Incubation phase: pathogen makes contact, grows, and repicates
-Prodromal phase: malaise (generalized ill-feeling) -Illness (invasive phase: symptoms and signs -Convalescent phase: recovery |
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Symptoms vs. Signs
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symptoms are effects experienced by patients
signs are effects observed by examination of patient |
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Local vs. Systemic
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local is contained at one site
systemic is a widespread infection in many sites of the body |
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List an example of a localized infection
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TB
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List an example of a systemic infection
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bacteremia, septicemia (bacterial infection that is out of control), viremia, etc
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Primary vs. Secondary infection
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a primary infection is an infection that weakens the immune system
A secondary infection is a 2nd infection that arises from an impending primary infection that is completely different from that of the primary infection |
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List an example of a primary vs. a secondary infection
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primary- influenza virus
secondary- hemophilus influenzae |
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List an example of an acute vs. chronic infections
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acute- varciella (chickenpox)
chronic- herpes zoster (shingles) |
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Epidemiology
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cause and spread of a disease
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Prevalence
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total number of existing cases in population over a given period
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Incidence
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ratio of new cases to healthy persons over a certain time period
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Morbidity vs. Mortality
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morbidity- sickness
mortality- death |
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Endemic
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expected amount of a particular disease that you would see in a population
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Epidemic
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significant rise above expected level of disease
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Pandemic
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world wide epidemic
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Sporadic
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limited in low numbers, isolated cases with no connection between them
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List a type of chronic infection
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latent infection-comes and goes, an infection that just simply gets worse
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Reservoir
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place in nature where an organism survives and replicates
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Source
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place or object from which a pathogen spreads to a new worse
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2 types of animate objects
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animals and humans
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Zoonoses
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an infection indigenous to animals but is naturally transmissible to humans
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Vector borne diseases (mechanical vs. biological)
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biological- actively participate in a pathogen's live cycle
mechanical- merely transports without being infected |
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Vector
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a live animal that transmits an infectious agent from one host to another (ex. mosquitoes)
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4 types of inanimate objects
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soil, water, food, formites
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List the "Five F's"
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fingers
food formites feces flies |
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Direct transmission
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portals of entry and exit overlap
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Indirect transmission
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pathogen exists outside of the host population for a period of time
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Horizontal transmission
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disease is spread through a population from one infected individual to another
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Vertical transmission
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transmission from one parent to their offspring via ovum, sperm, placenta or breastmilk
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List the general characteristics of staphylococcus
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-gram positive cocci
-catalase positive -salt NaCl positive |
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Catalase
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degrades hydrogen peroxide into water and oxygen.
H2O2 --> H2O + O |
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Staphylococcus is relatively resistant to...
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-disinfectants
-desiccation (drying out) -antimicrobics (due to staph that has acquired genes for penicillinase) |
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List the characteristics of S.aureus
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-yellow or gold colonies
-mannitol positive (bubbling appears) -hemolytic -DNAse positive -Coagulase positive |
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List the characteristics of S. epidermidis
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-non-pigmented colonies
-mannitol negative -non-hemolytic -DNAse negative -coagulase negative (CNS) |
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Hemolysins
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lyse erythrocytes
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Leucoidin
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lethal to leukocytes, helps incapacitate phagocytic line of defense
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List an example of disorder caused by an exfoliative toxin. List its effects
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Scalded skin syndrome
toxin that separates the epidermis from the dermis. most prevalent in babies |
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Characteristics of enterotoxin
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-preformed (toxins already in foods that usually acts in 4-6 hours)
-heat stable -vomitotoxin |
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Coagulase
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produces fibrin clots around the cell and camouflage the cell from phagocytosis stopping the action of host defenses and promotes staph
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Hyaluronidase
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spreading factor; promotes invasion by digesting intercellular glue (hyaluronic acid) that binds connective tissue in host tissues
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Staphylokinase
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fibrinolysin
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DNAse
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a nuclease, digests DNA
HCl will cause a cloudy precipitate to develop.a clear zone around an area of bacterial growth indicates that the DNA has been degraded. |
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Lipase
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digests lipids and lipoproteins which makes it easier for bacteria to colonize on skin surfaces
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Penicillinase
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inactivates penicillin
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Protein A
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binds to immunoglobins at the wrong end
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Pyoderma
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purulent skin infection
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Pyodermic infections
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-Furuncles
-Carbuncles -Impetigo Contagiosum |
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Furuncles
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inflammation of a single hair follicle or sebaceous gland that turns into a boil
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Carbuncles
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tunneling skin abscesses, deeper lesions created by an aggregation of furuncles
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Impetigo contagiosum
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bubble-like epidermal swellings, most common in newborns
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List the 5 Invasive staphylococcal infections
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-Osteomyelitis
-septicemia -pneumonia -enterocolitis -endocarditis |
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Osteomyelitis
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abscess formation in affected areas resulting in elevated lump leading to necrosis and breakage of bone marrow
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Septicemia
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bacteria in the blood that is out of control
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Pneumonia
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systematic secondary staph infection resulting in multiple lung abscesses and symptoms of fever, pain in the chest, and bloody sputum
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Enterocolitis
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superinfection
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Endocarditis
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inner lining of the heart, cardial abnormalities and destruction of the valves
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Cause of Toxic Shock syndrome
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absorbent tampons bind to magnesium ions. In the absence of magnesium, S. aureus is produced in much greater levels of the toxin TSST 1
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List the symptoms and characteristics of TSS
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-fever, vomiting hypotension, rash
-can occur in any age, in either sex |
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How is staphylococcus transmitted?
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-direct transmission
-nosocomial infections common (HA MRSA) -reservoirs include skin and nose |
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Characteristics of Mannitol Salt Agar (MSA)
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-7.5% NaCl selects for staph
-mannitol fermentation differentiates between S.aureus and S.epidermidis -fermenters produce acid which turns the pH indicator (phenol red) to yellow |
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S. aureus is nearly always coagulase ______
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positive
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List the characteristics of streptococci
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-gram positive cocci in chains
-catalase negative |
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List the cellular components of significance in streptococci
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-hyaluronic acid capsule
-M protein -fimbriae (attachment) -C carbohydrate -Cell membrane antigens |
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What is the significance of the Hyaluronic acid capsule in streptococci?
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young cells, is indistinguishable from the H. acid found in humans so it does not provoke the immune response
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What is the significance of the M protein in streptococci?
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resists phagocytosis
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What is the significance of the C carbohydrate in streptococci?
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lancefield group system, specialized polysaccharides or teichoic acids found on the surface of the cell wall wall that protects bacterium from being dissolved by the lysozome defense of the host
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What are hemolysis patterns based on?
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their reaction in blood agar
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Alpha-hemolysis
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greening, chemical reduction of hemoglobin
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Beta-hemolysis
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complete lysis of RBCs
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Gamma-hemolysis
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no hemolysis
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Streptolysins
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hemolysins that rapidly injure many cells and tissues including leukocytes, liver, heart, and muscle
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List the two types of streptolysin
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streptolysin S- oxygen stable
streptolysin O- oxygen labile |
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List the 5 Group A virulence factors
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-streptolysins
-streptokinase -streptodornase -hyaluronidase -erythrogenic toxin |
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Streptokinase
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fibrinolysin, activates a pathway leading to digestion of fibrin
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Streptodornase
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nuclease (breaks down DNA)
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Alternative name for hyaluronidase? Why does it go by this name?
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spreading factor
breaks down binding factor in C.T thus promoting the spreading of pathogen in the tissues |
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Erythrogenic toxin
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pyogenic (pus-producing) toxin
responsible for bright red rash, induces fever in the temperature regulatory center. Key toxin in scarlet fever |
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Streptococcus pyogenes (Group A)
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most severe streptococcal pathogen in humans
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List 5 disorders of streptococcus pyogenes
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-cellulitis
-impetigo contagiosum -necrotizing fascilitis -streptococcal toxic shock syndrome -ottis media |
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Cellulitis is an infection of the ....
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connective tissues
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List and describe the three disorders associated with cellulitis
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-septic sore throat (pus exudate over the tonsils that enlarges them and induces pain)
-puerperal sepsis (uterine infection) -erysipelas (redness of the skin and mucous membranes) |
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Impetigo contagiosum
*streptococcus pyogenes |
burning, itching papules that break down and form a highly contagious yellow crust
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Streptococcal Toxic Shock Syndrome
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Profound bacteremia and deep tissue infection rapidly progressing to multiple organ failure
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Ottis Media
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Streptococcus pneumonia, Inflammation of the middle ear occurring most often in children
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Define sequelae
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complications
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List two sequelae to Group A infections
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Rheumatic fever (heart)
Acute glomerulonephritis (kidney) |
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Explain Acute glomerulonephritis
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kidney cells are so damaged that they cannot adequately filter blood.
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How is streptococcus pyogenes transmitted?
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direct transmission, through aerosols and wounds
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How is streptococcus pyogenes identified?
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beta-hemolytic, and sensitive to bacitracin (Taxos A disc)
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Name the group B streptoccous
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S. agalactiae
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Characteristics of S.algalctiae
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-neonatal sepsis
-vaginal carriers may transmit to child during birth -beta hemolytic; resistant to bacitracin |
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Name the Alpha Strep and its characteristics
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S.viridans (causes dental caries)
-rarely pathogenic -may cause endocarditis (following dental surgery or injury to oral mucosa) |
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Name the Gamma Strep
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E. faecalis
causes opportunistic infections of wounds, blood, endocardium, and the urinary and GI tract |
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Name the characteristics of the gamma strep
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-group D enterococci
-tolerates bile, hydrolyzes esculin -widely resistant to antimicrobics (including vancomyocin) |
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List the three diseases of streptococcus pneumoniae
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-pneumonia
-otitis -meningitis |
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How many serological types are there of streptococcus pneumoniae
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over 80
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Which type of strain is most virulent in streptococcus pneumoniae?
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smooth strains (capsules)
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List the incidence percentage of streptococcus pneumoniae
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40-70%
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List the characteristics of neisseria
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-gram negative dipolcocci
-fastidious (require elevated levels of CO2 and chocolate agar) -may exist inside of neutrophils (GNID) -causes blindness |
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List the virulence factors of Neisseria
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-pilli (promote attachment)
-IgA protease (cleaves secretory antibody and keeps it from working) -Antiphagocytic capsule -Endotoxin |
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Endotoxin in neisseria gives rise to......
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fever and disseminated intravascular coagulation (DIC)
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Gonorrhea is a ________ tract infection and can be_________ and/or _______
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genitourinary
symptomatic, asymptomatic |
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List the disorder that arises as a complication of gonorrhea
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pelvic inflammatory disease (PID)
aka saplingitis, characterized by fever, abdominal pain, and tenderness. |
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Gonorrhea also cause conjunctivitis. List its alternative name
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opthalmia neonatorum
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List four disseminated gonococcal infections
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dermatitis, arthritis, meningitis, endocarditis
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What is the annual incidence of gonorrhea in the U.S?
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1-2 million
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How is gonorrhea spread? How many females are asymptomatic? males?
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spread through direct contact
females-60-80% males- 20-40% |
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Gonorrhea is usually mistake for three infections (mixed infections). Name them
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chlamydia, herpes, syphilis
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Name the antibiotic resistant strain of gonorrhea
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PPNG- penicillinase producing N. gnorrheae
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List the name of microbe that causes meningococcal disease
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N. meningitidis
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Where is the microbe implanted in meningococcal disease?
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nasopharynx
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List and explain two disorders of meningococcal disease.
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-meningoccemia (progresses to shock, necrosis of tissues in exterminates and loss of limbs)
-meningitis (permeate meninges of the brain and grows in CSF) |
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List 4 notable features of meningococcal disease
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-petechial rash into pupura (nonraised purple blotches)
-neurological damage -adrenal damage (Waterhouse-Friderichson Syndrome) -mortality rate approaches 30% in septicemia |
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How is meningococcous transmitted?
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via aerosols and close personal contact
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What are the carrier rates of meningococcus between and during epidemics?
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2-8% between
50-90% during |
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List the incidence peak rate of meningococcus. List predisposing factors.
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late winter/early spring
crowded living conditions and poor general health |
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Treatment of meningococcus
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polysaccharide capsular vaccines
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List the two types of Bacillus. Are they gram positive or negative?
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Bacillus anthracis
Bacillus cereus (food poisoning) Gram positive |
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Bacillus anthracis
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-cause of anthrax and model for koch's postulates
-primarily a zoonic disease (undergoes cycle of vegetative growth in soil and is returned in excrement where it can then sporalate) |
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List the 3 human infections of bacillus anthracis
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-Cutaneous (black, necrotic eschar, spores entering through cuts and abrasions)
-Gastrointestinal (acquired through contaminated meat) -Pulmonary (most lethal, aka 'wool sorter disease'. attach to macrophage and gain access through engulfment) |
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Bacillus cereus
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-widely found in nature (dusts, aersols)
-food-borne disease (enterotoxin production in improperly stored foods. symptoms disappear in 24 hrs) -reported in immunodepressed and drug addicts |
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Clostridum
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-gram positive, spore forming rods
-obligate anaerobes and catalase negative (can not invade unless tissue is dead and/or severely damaged) |
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Clostridium contains potent exotoxins that contribute to disease. Name them.
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tetanospasmin (tetanus toxin)
botulina toxin |
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Tetanus is also known by what name?
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lock jaw
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Where is clostridium tetani found? List its incubation period.
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in soil and in the intestinal tract of animals.
3 days to 6 weeks |
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Defense mechanisms of Tetanospasmin toxin
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-blocks inhibitory neurons in the CNS by binding to motor nerve endings and then traveling by axon to the spinal cord. There it binds to target sites that inhibit muscle contraction
-results in sustained muscle contraction (tetany) or "sardon sardonicus" |
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Name the preventative measure used for tetanus
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tetanus toxoid (DTP)
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3 therapeutic measures used in the treatment of tetanus
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-tetanus antitoxin (TIG: tetanus immunoglobin which neutralizes toxin)
-antibiotics -muscle relaxants |
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Botulism
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associated with eating improperly canned or preserved foods
-symptoms within 24-71 hours |
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Explain the mechanism for the botulism toxin
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prevents the release of Ach (acetycholine) from neuromuscular junction initiating the signal for muscle contraction eventually resulting in flaccid paralysis.
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Signs of botulism
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-thickness of speech
-weakness -double vision -respiratory difficulties |
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Infant botulism
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-most common type of botulism ('floppy baby syndrome")
-infection following the ingestion of spores -colonization of infant's gut leads to toxic production due to immature state of neonatal intestine and microbial flora |
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Wound botulism
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results in infection, then toxin production (in vivo)
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Clostridum perfringens
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-food poisoning (diarrhea, enteritis)
-gangrene from wound infection |
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List treatment of clostridum perfringens
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-wound debridement (surgical removal of dead/damaged tissue)
-hyperbaric oxygen therapu |
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Clostridium dificile
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-superinfections in gut
-diarrhea symptoms that lead to dehydration |
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Group A (GAS)
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Streptococcus pyogenes
*strept throat |
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Group B (GBS)
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Streptococcus agalactiae
*neonatal sepsis |
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Group D (GDS)
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Enterococcus Faecalis
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List the arrangement patterns of mycobacterium
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-slender, curved, non-spore forming rods
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List the makeup of the mycobacterium cell wall. Why is this important?
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cells walls contain mycolic acid (lipid)
-resists desiccation and chemicals -prohibits gram staining (acid-fastness) -acid fast bacilli (AFB) |
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List the virulence factor of mycobacterium.
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cord factor
produces serpentine cords in sputum specimen which prevents mycobacterium from being destroyed by the lysozomes of the macrophages |
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List characteristics of mycobacterium tuberculosis
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-respiratory infection initially, primary focal lesions appear in lungs
-macrophages ingest but do no kill and therefore is ingested intercellulary -extrapulmonary dissemination may occur -exposures cause positive skin test |
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In mycobacterium TB, focal lesions become...
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tubercles (granuloma consisting of bacteria, neutrophils, and macrophage) that are walled off and healed (calcified)
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Diagnosis of TB
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-AFB (acid-fast bacilli) in sputum which may show serpentine cord
-culture |
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2 tests in TB: delayed hypersensitivity
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- Purified protein derivative (PPD, solution taken from culture fluids of M.TB)
-Mantoux test (involved localized infections of PPD) |
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A positive test of Tb indicates history of exposure to Tb. What is the sign of a positive reaction in the body?
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induration (redness)
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Treatment of Tb
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-prophylaxis: isoniazid (INH) for positive skin tests, as well as rifampin, streptomycin ethambutol
-therapy: combination treatment for disease |
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Epidemiology of Tb
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-age, socioeconomic level, immune status
-antibiotic strains becoming common |
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Mycobacterium leprae is also known as....
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Hansen's disease (leprosy)- chronic disease of the skin and nerves
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How is leprosy transmitted? How long is its incubation period?
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direct transmission
long incubation period, years |
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List some of other forms of leprosy
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-tuberculoid: benign tubercles (contain bacilli and enlarged dermal nerves)
-lepromantous: malignant, usually in the immunosurpressed (lepromas on the facr causing disfigurement) |
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In Non-Tb Mycobacterium (NTM), where are strains usually found?
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as free-living saprobes
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2 examples of opportunistic infections of NTM
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-Mycobacterium avium complex (MAC) in AIDS patients: cause of secondary infection
-Non-Tb lung disease and skin infections: mycobacterium kansaii, fortuitum, bovis |
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Corynebacterium diptheriae
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bacteria: pseudomembrane in throat (greenish gray film in the white pharynx that gives rise to inflammation and causes asphyxiation)
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What does the diphtheria toxin do?
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inhibits protein synthesis, acquired from bacteriophage during transduction
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Treatment for diphtheria
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Toxoid that protects (DTaP vaccine or Td vaccine)
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Listeriosis (Listeria monocytogenes)
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-acquired from dairy products
-pregnant women and immune-compromised individuals at risk -prevented by pasteurization |
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Mechanism of listeriosis
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replicates within the cytoplasm after inducing phagocytosis directly from cell to cell avoiding the humoral response
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O (______) antigen
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somatic
all have this antigen, associated with endotoxic shock |
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H (______) antigen
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flagellar
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K (______) antigen aka _______
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capsular
Vi for Salmonella |
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Antigenic variability ___________
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provides the basis for serological types, measuring the degree of agglutination or precipitation
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MacConkey Agar
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lactose fermentation, contains bile salts and crystal violet that inhibit gram positive bacteria
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Lac + microbes
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E.coli
Klebsiella Enterobacter |
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Lac - microbes
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Proteus
Salmonella Shigella |
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Triple Sugar Iron Agar (TSI)
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Bright red, nonselective medium that indicates fermentation of sugars- glucose, lactose, and/or sucrose. As well as production of hydrogen sulfide
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IMViC series
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-indole production (I for indole)
-acid from glucose (M for methyl red) -acetyl methyl carbinol (acetonin) production (V for voges-Proskauer) -utilization of citrate as a carbon source (C for citrate) |
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Identification of enteric bacilli
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-gram negative rods
-all contain endotoxin (LPS) -lactose fermentation of MacConkey agar -Triple Sugar Iron (TSI) agar -IMViC Series -Urease -Motility |
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Normal flora (enteric bacilli)
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-stimulates the immune system
-produce some of the B vitamins and vitamin K -produce natural resistance to disease |
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Pathogens (enteric bacilli)
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-normal flora out of normal habitat
-virulence factors (e.g toxins) -primary pathogens (salmonella, shigella) |
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Extra-intestinal disease (e-coli)
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-UTI: urethra is invaded by its own endogenus bacterial colonists
-nosocomial infections (septicemia, pneumoniea,etc) |
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An intestinal disease of e-coli is enterotoxigenic e.coli. List its alternate name
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traveler's diarrhea
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An intestinal disease of e-coli is enteroinvasive e.coli. List its alternate name
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dysentary-like disease
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Hemolytic Uremic Syndrome (HUS). Explain and list its responsible strain.
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E.coli O157:H7
Caused by the toxic effect of the bacteria on the blood and kidney, leading to hemolysis and kidney damage and failure |
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Klebsiella sp
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chronic lung function promoted by LPS capsule which prevents phagocytosis
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Characteristics of Klebsiella sp
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-capsular antigen produces mucoid texture
-UTI (some strains urease positive) -bacterial pneumonia in 10% of the cases |
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Characteristics of Proteus
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-hydrogen sulfide positive
-UTI (urease positive) -wound infections |
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List the characteristics of salmonella
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-acute gastroenteritis
-septicemia: phagocytes spread infection -enteric fever |
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Acute gastroenteritis
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ingestion followed by multiplication and invasion of epithelial cells in 12-24 hours, diarrheal symptoms
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Enteric fever
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colonization of lymph nodes
chronic carrier state i.e typhoid mary |
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Epidemiology of salmonella
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-human to human transmission through fecal/oral route
-raw food and poultry products common in gastroentritis |
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Salmonella enteritidis are frequently components of the ________ of poultry
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normal flora
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Prevention and control of salmonella
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-sanitation (food prep, pasterurization)
-identify carriers -eliminate routes of spread -vaccinate travelers and military personnel |
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Is shigella more/less ineffective than salmonella? List its disease
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-more ineffective than salmonella
-disease: shigellosis or bacterial dysentery (disease of the large intestine) |
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Shigellosis/Bacterial Dysentery
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-incubation period of 1-7 days
-diarrheal symptoms early -ulceration of large intestine leads to dysentery with blood and mucus in stools |
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Botulism is associated with the _____ nervous system, while Tetanus is associated with the ________ nervous system
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peripheral
central |
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Prevention and control of shigella
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proper sanitation and identify carriers
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List the two pathogens of genus yersinia
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-yersinia entrocolitica
-yersinia pestis |
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Yesernia enterocolitica
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gastroentirits that is spread to humans by animals, ingestion of undercooked food and contaminated water
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Yersinia pestis gives rise to what disorders?
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bubonic and pneumonic plague
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List the reservoir and the vector for the bubonic/pneumonic plagues
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reservoir- rat
vector- flea |
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Bubonic plague
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swollen lymph nodes called buboes-usually in the groin
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Mortality rate of septiciemia
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90-95%
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Explain what happens in pneumonic plague and lists it mortality rate
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black death that is contagious through sputum and aerosols.
100% |
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Epidemiology of the plague
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"Sylvatic plague" occurs in wild animals
"Demic plague" person to person spread |
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List the virulence factor of Hemophilus influenzae
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capsule serves as a virulence factor (type b capsule is most virulent)
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Hemophilus influenzae
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-serves as either a primary or secondary infection
-formerly the most sig. cause of meningitis in children (Hib vaccine protects) |
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Hemophilus aegyptius
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conjunctivitis aka pink eye
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Hemophilus ducreyi
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STD aka soft chancre
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4 characteristics of Pseudomonas aeruginosa
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-obligate aerobe, non fermenter
-blue green pigment and grape like odor -ubiquitous in nature, soil, water and plants -highly resistant to antibiotics |
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Human infections of pseudomonas aeruginosa
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-pneumonia in cystic fibrosis patiets
-oppurtunist in wounds and burn patients |
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Bordetella pertussis is also called ______
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whopping cough
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Virulence factors of Bordetella pertusis
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pertussis toxin paralyzes cilia
receptors specifically recognize and bind to the ciliated epithelium, then toxins destroy and dislodge them |
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Stages of illness in Bordetella pertussis
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catarrhal: sneezing, coughing 1-2 weeks
paroxysmal- uncontrolled cough followed by whoop for up to 2 weeks convalescent- recovery period |
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Treatment for bordetella pertussis
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DTaP vaccine protects (aP= acellular pertussis vaccine)
administered in 5 dose series between 2 months and 6 years |
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Brucellosis is a zoonotic disease acquired from what specific animals?
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cattle (B. abortis)
pigs (B suis) or goats (B. melitensis) |
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Brucellosis
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-usually a subclinical disease
-acute illness may occur via phagocytes -may produce chronic infections with relapses up to 20 years |
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Synonyms of Brucellosis
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Bang's disease
undulant fever contagious abortion (in cattle) |
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Transmission of Brucellosis
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-common among abattoir workers
-dairy products from infected animals -crossbreeding spreads among animals |
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Francisella tularensis is also known by what name? What is it?
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rabbit fever (tularemia)
infection occurring via the skin or the eye through contact w/infected animal or animal products |
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Disease patterns of Francisella tularensis
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-ulceroglandular disease (wounds)
-typhoid like disease (ingestion) -pulmonary disease (inhalation) |
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Transmission of francisella tularensis
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direct from host or via vectors (ticks)
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Legionella pneumophila (lung-loving)
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-inhalation of aerosols initiates infection
-disease is more common in immune-compromised individuals |
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Symptoms of legionella pneumophila
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pneumonia and inflammation of the alveoli and bronchioles
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Disorders of legionella penumophila
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legionnaire's disease (1976) leading to impaired respiration and organ function
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