12 Flashcards
what is the chain of infection
modes of transmission
portals of entry
susceptible host
infectious agents
resivoirs
portals of exit
Ro
Reproduction rate- how contageous a pathogen is
what can describe malaria and chicken pox
they are endemic- outbreaks are predictable and constant
what pathogen has to be inside a vesicle
bacteria and parasites and fungi dont go in a cell
what are the symptoms of long covid
viral persistence
immune dysregulation
microbiome dysbiosis
endothelial inflamation
neuronal inflamation
mitochondrial dysfunction
why were civets thought to be intermediate species
becasue their sars-like CoV has more than 99% nucleotide homology
what are the stages of animal to human pathogen evolution
agent only in animal
primary infection
limited outbreak
long outbreak
exclusive human agent
what is the second stage of animal to human pathogen evolution called
primary infection
how do antibodies help with viruses
they can directly neutralize the virus or
help NK cells recognize the virally infected cell- ADCC
where is HCV found
in the liver- tissue tropism
genetic determinants of susceptibility
species level- protein homology
individual level- allelic variation can increase or decrease suscpetibility
what are the three 3 respiratory modes of transmission of infections
aerosolized droplets that are inhaled
larger droplets that land on mucosal membranes
fomites that are deposition on contact surfaces
what are the factors affecting respoitarty infection transmission
physical characteristcs
time
humidity
air flow
pathogen load
symptoms of polio
FLU LIKE
Polio eradication
resurgence in africa
one detected case of polio in
2022
how does the influenza and spanish flu virus work
has segmented genome
8 RNA that each encode for one of the viral proteins and the organism requires one of each 8 RNAs to be virulent but the similarity between viral species are similar enough for them to be able to mix and match and complement one another
does gene reassortment- antigenic shift
point mutations- antigenic drift
original antigenic sin/ imprinting
stronger response to a virus antigen that was previously recognized even though it has some new antigens
where does the herpes zoster virus stay latent
in sensory neurons
what does herpes zoster code for
varicella and chicken pox
what is shingles
a re activation of chicken pox virus
what does measels do to you
wipes out your immune memory making you suscpetible to diseases and reduces your antibody repitoir
what is the symptom for measels
topik spots lots of complications
what is subacute schlerotic panencephalitis
occurs 7-19 years after you recover from mealsels and is leathal and inc risk if you got measels before the age of 2
another name for cytokine storm
cytokine release syndromw
what does cytokine storm in lungs lead to
acute respiratory distress syndrome ADRS
what does an unregulated and dexaggerated release of inflamatory cytokines lead to
localized and systemic acute phase response mediated by hyperactivation of immune cells
how do bacteria evad the immune system
secrete proteases to degarade IgA
gram positive and some gram negative bacteria are resistant to complement mediated lysis
some bacterial surface structures like fibrin and M protein inhibit phagocytic cells and some can evade phagolysosomes in the cytosol
example of bacteria that degrades IgA
N gonorrhoeae
example of bacteria that evades phagolyssosme
mycobacteria tuberculosis
how does mycobacteria tuberculosis work
replicates inside cells and inhibits phagolysosome formation
caues formation of granuloma inside tubercle
release of lytic enzymes damages healthy tissue but infection is contained
antibiotics cant penetrade inside granuloma very well
what are the two types of parasites
protozoa and helminths
protozoa
unicellular
live and replicate in host
some require intermediate host like malaria and trypanomiasis
helminths
multicellluar
can reproduce and live outside of host
how do we defend against parasites
its difficult because generlzation is difficult- must depend on life stage and its location in our body
different defense against parasites in the body
bloodstream- humoral antibody
inside cells- cell mediated immune reactions NK and T cells
how do trypanosoma work
they have many different variants of key antigens
so our immune systems removes most of one type of antigen but the other type is replicated and our body misses it because it is a different variant
what do helminths/ worms cause
schistomsomiasis
how do we treat schistomsomiasis
sicne it is too big for phagocytosis, we secrete lytic enzymes (complement, basic protiens, ADCC)
igE antibodies are involved
how are fungal infections controlled
innate immune ssytem by physical barriers and commensal microorgansism
neutrophil phagocytosis and rectognized PAMP on PRR
how do viruses evade immune response
by evolving a capsule that blocks PRR binding so can have axquired immunity
which immune response pathways are related to autoimmunity
type I and III
what type of response is in type 2 immuity
allergy/ asthma
which immune response leads to CTL formation
type I
what does type II immune response lead to
TH2 acting with b CELL TO PRODUCE igE and igA
what does type III immune resonse lead to
TH17 cell interacting with B cell to produce igG
