Transcript Urushiol - Fat Tuesday Productions

Urushiol
Mechanisms of
Transmission
Urushiol can be Transmitted
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By contact with the
plants that contain it.
By contact with
inanimate objects which
have come in contact
with it.
By contact with other
living things that have
come in contact with it.
Direct Contact with the Skin
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The easiest, most
common way to get
dermatitis from urushiol
is to physically contact
any part of the plants
that contain it.
Often this happens
without notice –
symptoms may not
show up for several
days, if at all.
Poison Ivy
Poison Oak
Poison Sumac
Contact with Contaminated Objects
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These can include
clothing or shoes that
have contacted urushiol.
A guy was wearing
these pants when he
encountered poison oak.
His legs were covered in
blisters.
Urushiol can stay on
unwashed clothes for up
to a year.
Contact with Contaminated Objects
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Dead dry leaves still
contain active urushiol
for some time.
The same is true for
gardening tools.
Contact with Contaminated Animals
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Animals can get
urushiol on their fur and
have no reaction, but
can transfer it to
humans.
Once skin exposed to
urushiol has been
thoroughly washed,
human-to-human
transmission is nearly
impossible.
How does it work?
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Chemically, urushiol is harmless to humans.
However, when contacted, it bonds to deep
skin proteins.
This initiates a T-cell mediated immune
response towards the urushiol derivatives
which are bound up in the skin proteins.
The result is an allergic reaction characterized
by redness, swelling, and blisters.
What happens
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Urushiol causes an
allergic reaction (Rhus
dermatitis) in about
85% of people exposed
to it.
This percentage
decreases with age.
Breathing burning
urushiol can be
extremely serious.
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In severe cases there is a
risk of anaphylactic
shock.
As with many allergies,
reactions become more
pronounced with
repeated exposures.
Once a rash develops, it
can linger for up to a
month.
Examples of Reactions
Recurrence
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Strangely, a rash may
appear months – even
years – later, despite
there being no further
exposures.
References
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Poison Sumac http://www.poison-sumac.org/
Aetna Intellihealth
http://www.intelihealth.com/IH/ihtIH/WSIHW000/79
45/7991/442902.html
The University of Iowa
http://www.uihealthcare.com/topics/medicaldepartme
nts/dermatology/poisonivy/index.html
Poison Ivy, Oak and Sumac Information Center
http://poisonivy.aesir.com/view/comments.html?func
=showMessage&mid=100590&wid=279
Wikipedia http://en.wikipedia.org/wiki/Urushiolinduced_contact_dermatitis