ENWC201 Lecture Notes - Lecture 9: Chronic Wasting Disease, Mercury Poisoning, Epizootic
15 Jun 2018
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Department
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Amphibians are the most threatened
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Why are we concerned about wildlife diseases?
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Wildlife diseases are connected to:
Conservation of threatened and endangered species
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Recreational use of wildlife
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Public health/loss of life (pet and human)
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Agriculture (livestock)
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Basic disease vocabulary
Disease - a disturbance to the normal function or structure of an organism
Starvation is a disease
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Getting hit by a car is a disease
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Broad definition
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Epizootic - a disease that appears at an unexpected rate in animals,
synonymous with Epidemic in humans
White nose syndrome in bats
Currently on the east coast/mid
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Humans cant get it
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Infectious: Viruses, Bacteria, Fungi, Parasites (internal and external), etc
Pathogen - a disease causing agent
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Infectious pathogen example: chronic wasting disease (CWD)
When a protein is folded incorrectly = prion
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These prions cause other proteins to fold incorrectly
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This leads to disease (like mad cow disease)
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CWD occurs in deer
Causes them to drool
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Spreads the disease
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When it spreads to a new area they encourage harvest
of deer to limit the spread
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Non infectious: toxins (manmade, plant, fungal, or bacterial),
physiological, nutritional, congenital, degenerative, cancer
Non- infectious disease example: mercury poisoning
Mercury:
Product of coal and other fossil fuel power generators
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Heavy metal toxin -> methyl mercury
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Also emitted when items with mercury are incinerated
(thermometers, batteries, light switches, fluorescent
bulbs)
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Bio-accumulates, bio magnifies
bio accumulation - continuously burning
coal ,putting mercury into environment,
accumulating in animals
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Bio magnification - increased concentration as we
go up the trophic levels
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Reservoir: any living or nonliving substance that may perpetuate a
pathogen in nature
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Reservoir host: a host that acts as a reservoir for the pathogen, but does
not suffer ill effects from the disease
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Host: an organism on or in which another organism lives
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Vector: an organism that carries pathogens from one host to another, or
from a reservoir to a host
Biological vector
Has it inside its body□
mosquito□
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Mechanical vector
Has it on its body□
fly□
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Disease and agriculture
Brucellosis in cattle herds
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Bird flu outbreak in Tennessee
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Disease has a big impact on agriculture
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Disease and endangered species
Conservation of rare and endangered species
Common loon
Lake erie□
Avian botulism type E
Quagga and zebra mussels
invasive
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Algae beds
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Invasive round goby fish
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High mortality rate□
Over 1,000 loons killed on one lake□
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Serengeti lion
Tribal herders dogs get
Rabies
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Canine distemper
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Serious threat to the lion population□
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Increasing disease emergence
Why are we seeing the emergence of so many diseases
More people = more habitat alteration = more stress on animals =
more human/wildlife interactions
More stress on animals and more human/wildlife = increase
in diseases
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Sea otters
Oil spill
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High stress
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Latent herpes
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Zoonosis
Zoonosis: an animal disease that can be transmitted to humans - but we
are not necessary
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Example 1: Lyme disease
Cause: bacteria (borrelia burgdorferi)
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Transmission: deer tick and lone star tick
Reported cases of lyme disease - united states, 2011 - 112.2
cases in DE/100,000 people
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Symptoms and treatment
Rash, fever, swollen lymph nofes, etc□
Left untreated, further complications may arise such as:
meningitis, facial palsy, heart abnormalities and arthritis
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Example 2: west nile virus
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Example 3: avian influenza (h5N1)
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Example 4: SARS
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Example 5: Ebola
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Wildlife Disease
Saturday, April 7, 2018
8:53 AM
Document Summary
Disease - a disturbance to the normal function or structure of an organism. Getting hit by a car is a disease. Epizootic - a disease that appears at an unexpected rate in animals, synonymous with epidemic in humans. Infectious: viruses, bacteria, fungi, parasites (internal and external), etc. When a protein is folded incorrectly = prion. These prions cause other proteins to fold incorrectly. This leads to disease (like mad cow disease) When it spreads to a new area they encourage harvest of deer to limit the spread. Non infectious: toxins (manmade, plant, fungal, or bacterial), physiological, nutritional, congenital, degenerative, cancer. Product of coal and other fossil fuel power generators. Also emitted when items with mercury are incinerated (thermometers, batteries, light switches, fluorescent bulbs) Bio-accumulates, bio magnifies bio accumulation - continuously burning coal ,putting mercury into environment, accumulating in animals. Bio magnification - increased concentration as we go up the trophic levels.
