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microbiota Microorganisms that are normally present in and on the body
Usually present only in areas of the body in contact with the outside environment; no contact
(internal tissues, organs, fluids...") = sterile
resident microbes Each site has a relatively constant population, although it can alter a bit
over time and as we move environments
transient microbes Are typically passing through
opportunistic microbes Normal microbiota can sometimes cause opportunistic infections
Ex: weak immune system or when defenses are breached during surgery
formula fed babies Start with a mixed population of coliforms, Lactobacilli, Strep, &
Staph
,breast fed babies Start with Bifidobacterium-- organism colonizes milk duct then passes to
baby
pathogen Microbe that can cause disease in a susceptible individual
pathogenicity Organism's potential to cause infection or disease. More pathogenic = more
severe disease process
virulence factor Any characteristic or structure of the microbe that contributes to its
virulence
true pathogens Have the potential to cause disease in every individual, healthy or
immunocompromised
opportunistic pathogens Cause disease in immunocompromised hosts and not typically
healthy individuals (unless their immune systems are breached or they are temporarily
immunocompromised)
,steps of infection 1) Entry into the host (portal of entry)
2) Becoming established--attaching to the host
3) Surviving host defenses
4) Causing disease
5) Exiting host (portal of exit)
portal of entry The majority of pathogens are adapted to a specific portal of entry. If they
enter the wrong portal, they're not infectious. Occasionally, more than one portal can be used
Ex: Influenza causes disease via entrance to the nasal mucosa but will not cause a skin infection
Mycobacterium tuberculosis can enter through both the respiratory & gastrointestinal tracts to
cause disease
4 portals of entry 1) Skin [Staph boils, Tetanus, Herpes simplex 1]
2) Gastrointestinal tract [Salmonella, E. coli]
, 3) Respiratory tract [Influenza, Measles]
4) Urogenital tract [HIV, HSV-2]
portals of exit 1) Skin cells & open lesions
2) Insect bites
3) Removal of blood
4) Feces
5) Coughing & sneezing
6) Urine
microbe that can cross the placenta Treponema, causing Syphilis
perinatal infection Child is contaminated by pathogen in the birth canal
Ex: Herpes
T.O.R.C.H. infections 1) Toxoplasmosis