WaterborneDiseases_2010_to_post

WaterborneDiseases_2 - Survival
of
Pathogens
 
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Unformatted text preview: Survival
of
Pathogens
 
• 
 
• 
• 
 
 
 
 
 
 
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• 
 
 
 
Risk
is
not
as
high
as
it
may
seem.

Most
pathogens
require
rather
specific

 
condi9ons,
e.g.
target
9ssue,
environmental
condi9ons,
specific
substrates,
etc.
 
Pathogens
are
usually
not
well‐adapted
to
the
aqua9c
environment.
 
Self‐purifying
condi9ons
of
natural
aqua9c
environment
 
 
Dilu9on
and
sedimenta9on
 
 
Exposure
to
light
 
 
Starva9on
 
 
Preda9on
by
other
organisms
 
 
Lack
of
growth
 
 
Possible
loss
of
pathogenicity
 
Dose
and
exposure
depends
on
pathogen,
general
health
and
immune
status
of

 
the
host.
 
Commonality
of
waterborne
diseases
 
 
‐

poor
sanita9on
 
 
‐

oral‐fecal
route
of
transmission
 
 
‐

gastrointes9nal
illness
 Water
treatment
and
waterborne
diseases
 Snow
on
Cholera
 • 
1855,
physician
John
Snow
did
the
first
 epidemiological
study
showing
that
 cholera
is
spread
by
contaminated
 drinking
water.
 • 
Drinking
water
in
London
was
supplied
 by
private
companies
that
took
water
 from
different
sources.
 • 
S&V
Company
and
Lambeth
Company
 supplied
water
in
compe9ng
and
 overlapping
district.


 • 
Snow
took
a
detailed
survey
of
each
 house
with
a
cholera
death
and
what
 water
company
they
used.


 • 
First
7
weeks
of
epidemic,
315
deaths
 per
10,000
houses
with
water
from
S&V;
 and
37
deaths
per
10,000
houses
with
 water
from
Lambeth.
 • 
Rest
of
London,
57
deaths/10K
houses.
 • 
S&V
took
water
from
the
Thames
right
in
 town,
while
Lambeth
took
water
from
the
 river
several
miles
above
town.
 • 
Snow
suspected
this
knowing
that

 untreated
sewage
was
dumped
directly
into
 the
Thames.

 • 
At
that
9me,
there
was
no
knowledge
of
 the
bacterial
cause
of
the
disease.
 Typical
water
treatment
process
 This
is
the
same
process
that
is
found
in
the

 New
Brunswick
water
treatment
facility
on

 campus.
 WATERBORNE

DISEASES
 CHOLERA
 Humans
are
the
only
known
host;
exclusively
 Vibrio
cholerae

 waterborne
 
enterotoxin
 
massive
fluid
loss
–
up
to
20
L/day
 
dehydra9on,
death
in
2‐3
days,
60%
mortality
 
Peru,
1991
–
contaminated
fish,
fruits,
veggies;
>1M
cases;
>
10K
deaths
 TYPHOID
 Salmonella
typhi

‐
specific
to
humans,
sole
source
of
infec9on
 
contaminated
food
 
dose
dependent:

103,
107,
109/ml
=
0/20,
16/32.
40/42
clinical
disease
 
incuba9on
1‐3
wks,
fever,
headache,
anorexia,
enlarged
spleen,
cough,
cons9pa9on
 can
carried
in
gall
bladder
 Story
of
Typhoid
Mary:

early
1900s,
employed
as
a
cook
in
different
households
and
 ins9tu9ons;

iden9fied
as
the
source
of
contamina9on
and
thought
to
be
a
carrier
in
her
 gall
bladder;

imprisoned
for
3
yrs
&
released
with
promise
not
to
handle
food
or
cook,
and
 report
to
the
health
dept.
regularly;
disappeared,
changed
her
name,
con9nued
to
cook
in
 different
places,
and
con9nued
to
be
the
source
of
infec9on;
caught
during
a
hospital
 epidemic,
imprisoned
again
and
not
released.
 1.
Normal
process;
2.
Adherence
and
coloniza9on
of
 microvilli,
then
produc9on
and
binding
of
A‐B
 enterotoxin
toGM1
ganglioside;
3.

B
binds,
A
 releases
&
moves
across
cell
membrane;
disrupts
Na
 influx;
4.
causes
loss
of
Cl
and
HCO3;
5.
changes
ion
 balance
leading
to
large
ouklow
of
water
into
GI
tract.
 *Purified
B
subunit
without
A
subunit
actually
 prevents
ac9on
of
cholera
toxin
if
administered
first,
 because
B
blocks
the
binding
and
ac9va9on
of
the
 complete
A‐B
toxin.
 SALMONELLOSIS 

 S.
paratyphi,
S.
enteri4dis
–
enterotoxin
similar
to
cholera,
deliberate
act
of
infec9on
 
2000
different
serotypes 
in
1984,
salad
bar
in
Oregon,
751
cases.
 
incuba9on
12‐36
hours,
nausea
vomi9ng,
cramps,
diarrhea,
fever,
headache
 
generally
less
severe
GI
infec9on
 BACTERIAL
DYSENTERY,
SHIGELLOSIS 
Shigella
&
E.
coli
have
70‐90%
DNA
homology
 Shigella
dysenteriae,
S.
flexneri,
S.
boydii,
S.
sonnei 
 
generally
self‐limi9ng
 
high
incidence
in
restricted
groups,
nursing
homes,
day
care
centers
 
S.
dysenteriae
most
severe,
produces
endotoxin,
bloody
diarrhea 
 
 
 

 
infec9ve
dose
as
small
as
10,
incuba9on
12
hrs
to
7
days
 GASTROENTERITIS
 
E.
coli
 
most
are
self‐limi9ng,
but
the
O157:H7
strain
can
be
lethal
 
different
types
of
toxins,
heat
stable,
heat
labile,
severe
diarrhea,
vomi9ng,

 
O157:H7
serotype,

toxins
related
to
Shigella,
enormous
fluid
loss
 
hemoly9c‐uremic
syndrome
HUS,
immune‐compromised,
young
and
elderly
 
undercooked
hamburger,
apple
juice,
spinach
 Yersinia
enterocoli4ca
 
acute
gastroenteri9s,
incuba9on
24‐48
hours
 
reservoir
in
domes9c
and
wild
animals
 
cold
resistant,
grows
in
4°C,
mostly
found
during
cold
months
 Campylobacter
fetus,
C.
jejuni 
 
undercooked
poultry
contaminant
 
in
municipal
water
and
clean
mt
streams 












not
related
to
bad
water
quality
 
seasonal,
more
in
fall,
winter
 Table
4.1

Minimal
Infec9ve
Doses
for
Some
Pathogens
and
Parasites
 Organisms 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Minimal
infec9ve
dose 
 
 

 Salmonella
sp 
 
 Shigella
sp. 
 
 Escherichia
coli 
 Vibrio
cholerae 
 Giardia
lamblia 
 Cryptosporidium 
 Entamoeba
coli 
 Ascaris 
 
 
 Hepa99s
A
virus 
 
 
 
 
 
104
to
107
 
10
to
102
 
106
to
108
 
103
to
109
 
10
to
102
cysts
 
10
cysts
 
10
cysts
 
1
to
10
eggs
 
1
to
10
plaque
forming
units 
 
 
 
 
 
 
 
 

 

 PNEUMONIA
 Legionella
pneumophila
 
‐
named
aper
the
first
iden9fied
epidemic,
1976,
American
legion
conven9on
in

 
 
Philadelphia,
spread
from
air
condi9oning
system.
 
‐
aerosol
dispersion
and
infec9on,
acute
pneumonia

 
‐

respiratory
failure
15%
fatality
 
‐
Pon9ac
fever,
mild
nonfatal
version
 
‐
ubiquitous
in
natural
oligotrophic
waters
&
soils,

 
 
in
engineered
building
water
systems
 
*This
is
a
waterborne
disease
but
not
transmiqed
through
the
oral‐fecal
route
 VIRAL
DISEASES,
enteric
viruses
 Hepa99s
A,
infec9ous
hepa99s
 
‐RNA
virus,
liver
infec9on,
liver
damage
–
will
predispose
to
liver
infec9ons,

 
 
cancer
 
‐
heat
tolerant,
in
contaminated
water,
undercooked
food
&
shellfish
 
‐
different
from
Hepa99s
B
(DNA
virus),
serum
hepa99s,
only
through
close

 
 
contact,
needles,
body
fluids
 Poliomyeli9s‐documented
waterborne,
but
not
in
last
50
yrs
in
US
 Viral
gastroenteri9s
–
usually
self
limi9ng
 Norwalk
virus
–
Norovirus,
main
problem
in
all
the
cruise
ship
illnesses
 Rotavirus
 Table
4.4

Major
Waterborne
Bacterial
Diseases
 Bacterial
agent 
 
 
Major
disease 
 
typhoid
fever 
 
paratyphoid
fever 
dysentery 
 
cholera 
 
 
gastroenteri9s 
gastroenteri9s 
gastroenteri9s 
acute
respiratory 

illness 
 
 
 
 
 
 



Major
reservoir 
Site
affected 
 

 Salmonella
typhi 
 
 Salmonella
paratyphi 
 Shigella 
 
 
 
 Vibrio
cholerae 
 
 Enteropathogenic
E.
coli Yersinia
enterocoli=ca 
 Campylobacter
jejuni 
 Legionella
pneumophila 
 
 
 
 
 
 
 
 
 
 
 



human
waste 
 
GI
tract
 



human
waste 
 
GI
tract
 



human
waste 
 
lower
GI
tract
 



human
waste 
 
GI
tract
 



human
waste 
 
GI
tract
 



human/animal
waste 
GI
tract
 



human/animal
waste 
GI
tract
 



impounded
 
 
 
lungs
 




oligotrophic
water
 
 
 
 
 
 
 
 
 

 PROTOZOAN
DISEASES
 Giardiasis,

Giardia
lamblia
 
‐
currently
in
US
most
frequent
iden9fied
cause
of
waterborne
disease
 
‐
found
in
clean
recrea9onal
&
mountain
waters
 
‐
widely
found
in
potable
water
supplies,
16‐80%

 
 
surveyed
found
to
be
posi9ve
for
Giardia
 
‐
not
found
in
groundwater
due
to
extensive
natural
 
 
filtra9on
and
sedimenta9on
 
‐
animal
reservoir,
50‐95%
animal
pop.
infected
 
‐
very
low
infec9ous
dose
of
resistant
cyst
 
‐
small
intes9nes,
long
incuba9on,
hard
to
diagnose,
typically
visual
iden9fica9on
 
 

with
immunofluorescent
an9bodies.
 
‐
maladsorp9on
and
GI
distress,
can
last
months
to
years
 
‐
widely
distributed,
cysts
resistant
to
low
temp,
chlorine
 Cryptosporidiosis,
Crytosporidium
parvum
 
‐
inden9fied
in
1976,
human
pathogen,
carried
in

 
 
domes9c
animals
 
‐
1993,
Milwaukee
outbreak,
400,000
infected,
>50
deaths
 CDC.
Cryptosporidium
cysts
 
 
excessive
rain,
high
loading
rate
&
faulty
water
treatment
process
 
‐
found
in
domes9c
farm
animals,
probably
the
source
of
the
Milwaukee
outbreak
 
 
agricultural
run‐off
from
heavy
rain,
insufficient
chlorina9on
since
Crypto
cysts

 
 
are
high
Cl
resistant
 
‐
upper
GI
tract
infec9on,
not
generally
fatal
but
serious
illness
in
young,
old
and

 
 
immune
compromised
 
‐
low
infec9ous
dose,
Cl
resistant
cyst,
14X
more
resistant
than
Giardia
 Amoebic
dysentery,
Entamoeba
histoly4ca
 
‐
3rd
most
common
parasi9c
disease
in
the
world,
500,000/yr,
100,000
deaths
 
‐
asymptoma9c
carriers
can
shed
cysts
for
months
to
years
aper
infec9on
 
‐
no
documented
outbreak
in
US
for
30
yrs
 
‐
sensi9ve
to
disinfec9on
and
waste
treatment
 Waterborne
disease
outbreaks
in
the
U.S.
 • 
Waterborne
disease
is
no
longer
 limited
to
bacterial
infec9on
from
poor
 sanita9on
in
the
developed
countries.
 • 
Does
that
mean
that
water
and
 wastewater
treatment
design
is
no
 longer
appropriate?
 PARASITES
 Schistosomiasis,
S.
mansoni
(liver),
S.
japonicum
(bladder)
 ‐
not
found
in
U.S.
but
affects
500M
people
globally,
SE
Asia,
tropical
regions,
in

 
impounded
waters,
half
the
popula9on
of
Egypt
where
incidence
was
small
un9l
the

 
Aswan
Dam
was
built
 ‐ 
parasi9c
worm
with
complex
life
cycle
lives
in
blood
stream
(10‐30
mm),
blocks

 
blood
supply
to
organs
 ‐ 
human
carriers
excrete
eggs


 



hatch
in
water





specific
 
snail
host



small
worms

 (1‐2
mm)
in
water,
seek
human
host
 ‐
best
control
is
control
of
vector
 CDC
 Regional
differences
(all
diseases)
 
 


Changes
with
9me
(waterborne
diseases)
 Outbreaks
of
emerging
and
reemerging
infec9ous
disease
 This
illustrates
epdiemic
outbreaks
of
significant
but
rare
diseases
that
have
the
poten9al
 for
causing
more
global
epidemics.

HIV
and
influenza
are
not
shown.
 EMERGING
AND
RE‐EMERGING
DISEASES
 1.

Infec9ous
disease
–
within
last
5
yrs,
3rd
highest
ranked
cause
of
death
in
US.

5/10
top
 causes
of
death
related
to
infec9ous
disease,
pneumonia,
AIDS,
chronic
liver
disease,
 chronic
lung
disease,
immunosuppression.
 
Since
1980
death
rate
from
infec9ous
disease
increased
>50%
 Major
reasons
for
re‐emergence
 
a.

An9bio9c
resistance
 
 
e.g.
10
yrs
ago
resistant
strains
of
Streptococcus
pneumoniae
uncommon
 
 
 
now
40%+
of
strains
are
resistant
to
penicillin
and
other
Ab.
 
 
Overprescribing,
indiscriminant
use
in
domes9cated
animals,
caqle,
pigs,


 
chicken,
fish
farming.
 
b.

Demographics
and
social
factors
 
 
1950 
 
2
million
visitors
to
US
 
 
1990 
 
280
M
 
 
•

also
reverse,
more
US
ci9zens
traveling
to
remote
and
exo9c
loca9ons
 
 
•1900,

1.5%
world’s
pop.
lived
in
ci9es
 
 


2000,

50%
 
 


2020,

80%
 
 
 
borne
 
c.

Global
economy
and
trade
 
 
foodborne
diseases
associated
with
greater
imports
of
fruits
and
veg.
all
year
 
 
around
from
Central
and
South
America,
>60%
imported
in
winter
months.
 
 
O157:H7

E.
coli
in
hamburger
meat
imported
from
4
countries
 
d.

Economic
development
and
land
use
 
 
Aswan
Dam
in
Egypt,
2
mill
acres
–
schistosomiasis,
Rip
valley
fever,
mosquito
 
e.

Global
warming
–
the
spread
of
tropical
warming
into
temperate
zones

 
 
conducive
to
diseases
normally
limited
to
the
tropics.

Climate
condi9ons

 
 
suppor9ng
organisms
and
vectors.
 

 
 ...
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This note was uploaded on 10/25/2011 for the course ENVSCI 411 taught by Professor Young during the Spring '11 term at Rutgers.

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