bacterial pathogens Flashcards
bacterial flora is
endogenous
endogenous bacteria
bacteria that naturally reside in a closed system
when does disease occur
when microbes including in normal bacterial flora enter a sterile area of the body such as the brain or muscle- endogenous infection
example of endogenous infection
when E.coli of GI tract enters urinary tract- uti
exogenous bacteria
microorganisms introduced to closed systems from the external world- can either be benign or pathogenic e.g. cholera
clostridium in being exogenous
can be introduced into a closed ecosystem as well, having mutualist benefits for both the microbe and the host
what can control the spread of infection
social and environmental factors; vector control, chemoprophylaxis, outbreak investigation, food safety, health education
examples of HCAI- hospital acquired infections
-intravenous canulae; surgery; skin infection; urinary catheter; Gastrointestinal infection
gram negative bacteria
thin peptidoglycan- stay red since cant retain dye
all proteobacteria are
gram negativw
Neisseria meningitidis- type of bacteria
beta proteobacteria
Neisseria meningitidis
carried in the nasopharynx in 10-15% of population- epidemics occur every 10-12 years. classified by serogroup
serogroup
these microorganisms, viruses or cells are classified together based on their cell surface antigens, allowing the epidemiological classification of organisms to the sub-species level
-reactivity to a bacterial polysaccharide capsule
how many serogroups of N-meningitidis
12, 6 of which (ABCWXY) can cause epidemics
serogroups are based on
cell surface antigens
vaccines available for Neisseria meningtidis
a meningococcal A conjugate vaccine, tetravalent A, C, Y and W conjugate vaccine and meningococcal polysaccharide vaccine
gram positive bacteria
these bacteria retain the crystal violet dye (one of the main chemicals used for gram staining
example of a gram positive bacteria
Corynebacterium diptheriae
Corynebacterium diphtheria causes
diptheria
diphtheria was first reported in
4th century