Micro exam 2

• a pathogen is any disease causeing microorganism
• parasite 

primary and opportunistic pathogen

often requires an extended relationship or coexistence betwen parasite and host.

an example of symbiosis.

several hosts.

definitive host is the final host which maintains the mature for m of the parasite and has the sexually reproductive form of the parasite

intermediate host is what maintains the immature parasite and its where it undergoes various stages of development before being transferred to the definitive host.

ectoparasites are organisms that live on the surface of a host.

endoparasite are organism that lives on the inside of the host.

exogenous are infections that reslut from enoucnters withpathogens in the environment.

endogenous are acquired infecitons that caused by pathogens or pothential pathogens in or on the body.

based on the babiliy of the pathogen to invade and live within host cells

obligate intracellular pathogen

facultative intracellular pathogen

the process by which microbes cause disease in a host. steps involved in diesse progression wihtin the host.

theability of microbes to cause disease an the capacity of a pthogen to invade and harm a host.

• physicall/structural factors 
•  (capsul, outer membrane)
• biochemical factors - proteins (toxins)
• Genetic factors- resistance genes

related to virulence

• large segments of dna that code for virulence factors; often acquired during horizontal transfer
• clusters of pathogenicity genes encoding virulence factors

a nonspecific defense mechanism by the body in response to infection, injury or chemical irritation.

• rubor: redness from blood acculmulation
• calor: heat caused by the blood due to vasoconstriction
• tumor: swelling or edema from the accumulation of fluid in surrounding tissue
• dalor: pain soreness or tenderness from injury to local nerves
• sometimes itching (pruritus)

crdt

• vascular hcanges
• increase in vascular permeability
• leukocyte migration
• chronic inflamation
• resulution and healing :
• collagenation
• angiosensis
• proliferation
• remodeling

• bacteremia
• fungemia
• viremia
• toxemia
• speticemia is whenn there is bloos poisoning and multiplying microbes in the bloos; prescence of toxins

cytopathic effects

• viral overload
• cytocidal effect
• non-cytocidal effect

permanent damage to tissues as a reslult of infection adn disease.

is when etiology, pathology and the prognosis is unkown.

is the study of the frequency and distrivution (spread) of disease and other health-related problems within human populations.

• bacteria
• fungi
• protozoa
• parasitic worms (helminths)
• viruses

infection includes the signs and symptoms that result from the growth of miccrobes and their invasion into tissue.

are the signs and symptoms that are the result of the acion of toxins.

• clinical are when the signs and symptoms are clearly evident and commonly referred to as a overt, apparent or symptomatic infection that included acute, fulminating, and chronic.
• sub-clinical is when the patient lacks symptoms and the infection is not yet detected by clinical examination or laboratory tests and are also called asumptomatic , inapparent, subvert, and covert infections.
• latent infections are when the microbe persists  in a dormant state in host tissues for long periods of time and the pathogen cannot be found by culturing and the disease alternates between an acute and a subclinical state.

• local microbes are restricted to a limited region or anatomical area- abscess
• focal is when the infection spread from one localized are to otehr localized areas - tuberculosis
• systemic is also called disseminated or generalized and it is when microorganism circulates throughout the body and infects many different tissues-measles or typhoid.

• primary infection
• secondary infection
• superinfeciton

Polymicrobial infection is when the ismultaneous establishment of infection by several different microbes and also reffered to as a mixed infeciton


cross infection is the co-infection of a host by pathogens when they are transmitted between hosts.

infectious diseases that are acquired and/or developed in hospitals.

infection resulting from endogenous microbiota when the host immune's system is compromised or if the microbe moves from its normal location to a new location in the body.

infection resulting in pus formation

infection resulting in fever; fever-inducing-febrile or pyretic microbes that induce fever.

time from the first exposure to the pathogen tothe thime symptoms become apparent.

depends on the health of the host, the virulence of the microbe, the generation time of the pathogen, thime for organism to migrate from point of entry to site of infeciton.

a short period before specific symptoms set in where the patient experiences malaise, general feeling of discomfort such as joint pain, headache, or muscle ache.

the patient's condition worsens and the patient's immune system is working to contain and eliminate the microbe but has thus far been unsuccessful, elevated white blood cells, high levels of immunological molecules and antibodies, and the patient either recovers or the diseas is fatal.

recovery period in wher the patient survives the infeciton and microbes and otoxins are eliminated from the body and signs and symptoms abate and patient starts to feel better and the affected tissues and systems are repaired.

Ipidc

diseases caused by factors other than microbes.

• inherited
• congenital diseases- except teratogens and microbes causing
• degenerative diseases- except prions
• nutritional deficiencies- except parasitic worms
• endocrine diseases- except enteric microbiota
• mental diseases- except toxoplasma which causes herpes simplex virus
• immunological diseases- except sequela and hiv/aids
• neoplastic diseases-exept hpv cervical cance;ebv and burkitt's lymphoma
• iatrogenic disease-except nosocomial infections
• idopathic diseases

• maintenance of the pathogen
• transmission
• penetration of host
• colonization
• persistense-evasion of host defenses
• reproduction
• invasion and toxigenicity
• dissemination and portals of exit

• animal
• human
• environmental

• sars which is the corona virus in bats and pigs.
• avian or bird flue such as the h5n3 influenza in birds
• plague which is caused by the yersinia pestis from rats
• cutaneous antracis which causes anthrax from cattle

• symptomatic carriers
• asymptomatic carriers such as incubatory carriers chronic carriers and latent/dormant carriers.

• soil
• water
• food
• air
• house dust
• arthropods
• fomits

• ticks
• fleas
• mites
• flies
• lice
• mosquitoes.important in the spread of zoonotic diseases.

Mechanical vectors that live on the external surfaces of the vector and the organism is not involved in the life cycle of the pathogen

Biological vectors are when the pathogen lives withing the body of the vector and often serves as the definitive host and also that the vector transmits the pahtogen by biting, sucking, and aerosol formation.

• common housefly
• cockroach

biting and blood sucking vecotrs such as flies (sand flies and tsests flies) mosquitoes, lice, tick, mites, and fleas.

mosquitos inject saliva infected with the pathogen directly into the blood.

fleas penetrate the skin and dfecate around the wound and thereby introducing pathogen into the host

tsetse fly penetrate the skin and regurgitate infected blood into the wound.

biological

is when the pathogen is deposited directly into the blood stream, into tissue below the skin or into mucous membranes through injections, deep wounds, and insect bites.

• mucosal surfaces:
• urogenital tract
• digestive
• respiratory
• and conjuctiva (mucosal linding of the eye)

• mouth through ingestion of contaminated food and live in the stomach pH enzyme activity.
• salmonella, poliovirus, hep a viruse

• nose which is the pathogen that enters the body thorugh inhaled droplets or aerosols
• or through bacteria in such as (streptococcus) that causes sore trhouat, meningitis, diphthereia, and pneumonia
• viruses include the measles, mumps, chickenpox, and cold

the establishment of a site of reproduction of the pathogen and  an apporpriate portal of entry

the structures involved in colonizations are considered virulence factors becaseu adherance mechanisms and ways to overcome or withdstand the constant pressure of the host defeses at the surface are required.

after colonization, many pathogens penetrate the host's mucous membranes and epithelial surfaces and the active mechanisms produce lytic enzymes that alter the host tissue while the passive mechanisms participate in pre-existing tissue damage and in existing internalization methods such as in endocytosis and phagocytosis.

• to hide from the immune system
• to avoid destruction by the immucne cells
• to persis and multiply within the host.

• asexual
• binary fission (eukaryotes nad transverse or longitudinal fission)
• budding
• schizogony
• fragmentation
• sexual reproduction
• bacteria nd protists
• conjugation
• the use of gametes

• cytotoxins because the site of action is in the cytoplasm
• for diseases like diphtheria and botulism, the symptoms arealmost entirely casued by toxins rather than by the body's immune response.

• resulting in cell death
• cancer causeing
• damage to the fetus

• repiratory and salivary: sneezing coughing and coughing and spitting
• skin which includes sweating
• fecal which includes defecation
• urogenital withch includes urinaition
• blood and bleeding

• phend
• paralytic
• hallucinogenic
• emetic
• neoplastic
• diarrheal

• produced as proenzymes within the microbe; this form is incatve.
• botulinum toxin

once it leaves the cell (enzymatic cleavage or phosphorylation)

bacteriocins

listed by the body system they target in humans

when bacteriocins are used to kill other bacterial infections in the human body.

they stimulate the immune system

a grop called mycotoxins such as a flatoxin which ar eof the most napotent toxins 

phycotoxins such as cyanobacteris (bacteria) and dinoflagellets (protozoa)

exotoxins are toxins secreted by live bactria

endotoxins are toxins released when the bacteria dies.

• exotoxins are toxins released into the surrounding area
• endotoxins are toxins that are critically associated with the bacteria.

• exo is when thte toxin work on intracellular targets of the host cell
• endo is whenthe toxin works at the surface of the host cell

• yes
• yes

proteins and enzymes

• intracellularly
• most of the exotoxins are potent becuase they are enzymes that catalyze the covalent modification of intracellular targets and have creative mechanisms for overcoming the barrier of the plasma membrane.

• 1. cytotoxins: type I-v
• 2. ab toxins
• 3. cytolytic toxins
• 4. superantigens

• because the action of the toxin is within the cytoplasm
• the toxin is secreted directly into the cytosol in a contact-dependent manner

• cytotoxins are effictient in the sense that the poison enters only the target cell.
• cytotoxins are selective in the sense that intracellular target is specific.

gram positive

plasma membrane of thehost cell

inhibit the synthesis of proteins

escapes from host cells

gram negative

molecular syringes that resemble flagella (type 3)

molecular syringes that resemble conjugative pili (type iv)

• binds to cell surface receptors of host
• helps to translocate the a domain/subunit

• transferred across the plasma membrane into the host cell
• enters the cytoplasm and enzymatically acts on host tragets

diphtheria toxin

cholera toxin

anthrax toxin

interact at the host membrane before entry