Summary notes Microorganisms Infection and Immunity 2

MII




2021122

, Ll -
The challenge af Microorganisms




pathogens ~



microorganisms /infectious agents
that cause disease .




"

development
"


Malaria , HIV/AIDS TB three killers there's been treatment
big
=
→ so
,

f f f deaths have
fallen .




627,000 15m deaths in 2020
680 , no



court -19 →
3m
(in 2020 ) ,
over 5m
(by 2022
)

www.gg.ny.a.uga.g.ag.mn ,



Comptes due
to :




Co
1.
infections fey TB
-




infection + HIV co -




2. Healthcare resources
④ Covid
appealing
healthcare
system globally ; TB death rose in
)
2020

Wider impacts
(wide of life, top of death
3.
being
societal health and
quality
or economic impacts on , well -

on


t




}
wide

impacts

→
of infectious
desiseas that

go beyond
death .




f
opportunistic f
infection occurring
in
immunocompromised "
enters brain and is

but
individuals dormant
threatening
"




for immunocompromised
individuals

,How do ?
acquire infections
we

Via e¥t or host through physical contact /
ingestion / inhalation / vectors .




Many microorganisms have exploited mucosal sites for transmission as
they are


involved in

many processes eg breathing , reproduction → results
leg
in
major
TB , AIDS , con 'd , diarrhoea
diseases
)
.




Shin acts as a natural barrier -



/
but abrasions cuts / bites can make host vulnerable
to
infection ( tetanus ,
malaria
)
Mucosal
immunity is
highyspeiaised so
developing mucosal vaccines is
challenging
Not disease
microorganisms
all cause


104
hum-anmi.CH =



microorganisms
↳
many beneficial functions (digestion / synthesis/ protection )
nutrient + rit



#
genes
within human microbiome >> human
genome (40 -1W :
1
)
ratio




what makes
microorganisms harmful ?
combination
of
microbe -




specific f host-specific
(
virulence
factors) ( inflammation)

hosts adapt to each other
site-specific host
microorganisms
via or
specific ways
+ -




t to
intra host
-


adaptation inter host
-



adaptation
t tr
immune could
ignore
at
microorganisms crossing
microorganisms species barriers
me

anatomical site but Mat may
produce disease in one
at another host but not in another

⑨↳ Zoonotic
infections)
60% all umanh
of
pathogens are zoonotic

, Zoonotic
infections are
very unstable due to differences in host immune
systems 4
pathogen biology
t
Bats due to
are
great carriers
of
zoonotic infections :




1) suppression
of
viral
infections by continuous interferon activity (
innate imm
)
a) awn
unusually large naive antibody repertoires that don't need rapid

affinity maturation for limiting
viral
(adaptive imm) .




71400 but that harbour >
3000
species coronaviruses



virus mutations are random and can enhance transmission virulence r immune
,

evasion
(depending on opportunities /selective pressures
)
risks CFRS)
case
fatality risk ( matter as
,
although they are estimates,
they influence
perceptions vs hazard
of
.




↳ hazard death scares population so
changes mass behaviour
if
=


,

how diseases
appealing infectious are
managed .




Zoonotic be exploited for the benefit of human health
microorganisms
can



eg cowpox ( ) protects against smallpox ¢FR= 80%)
mild in humans




↳ with this vaccination was due to
success
egoicacy of vaccine
for
herd that it humans
inducing immunity only infected
+
.