Download The Virus

THE
West
Nile
Influenza
HIV
What is a Virus?
• Virus ~ Infectious agent made up of a core of
nucleic acid and a protein coat.
Virus = Poison
• Not a living organism (Must have a HOST)
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Is not a cell
Does not contain cells
Do not eat
Does not respond
Viral Structure
• Does not contain a nucleus
• Very small
• Composed of three (3) parts
– Capsid - Protective coat
around core
– Nucleic Core
– Envelope - layer which
surrounds the capsid
• Recognizes and binds to host
for viral infection
Viral Replication
• Virus’ do not reproduce they replicate
• A host is required for replication
– Host ~ organism which shelters or nourishes something
by providing materials necessary for viral replication
How does a Host become infected?
– Envelope contains specific proteins which bind to
receptor sites.
Viral Infections
Influenza, commonly called "the flu," is an illness caused
by viruses that infect the respiratory tract.
Symptoms:
•fever 100° F to 103° F in adults
•higher in children
•respiratory symptoms such as,
•cough,
•sore throat,
•runny or stuffy nose,
•headache,
•muscle aches, and
•extreme fatigue.
Viral Infections
Rabies
•People usually get
rabies from the bite of a
rabid animal.
•Rabies can be
confirmed only in a
laboratory.
Varicella common name “Chicken Pox”
•rash on the skin.
•occurs mostly in winter
and spring, but can
happen any time of the
year.
•Very contagious
•90% of all people in
the world will
experience chicken pox
at some time during
their lives, unless they
receive the vaccine.
Polio
•Polio is a disease that is able to damage the
nervous system and cause paralysis.
•The poliovirus enters the body through the
mouth.
•Non-paralytic polio will result in fever,
vomiting, abdominal pain, lethargy, and
irritability.
•Some muscle spasms in the neck and back,
with muscles generally tender to the touch.
•Polio was declared eradicated
•in the U.S. in 1979
Measles
Symptoms: fever, listlessness,
loss of appetite, mild head
cold, sore throat, dry cough,
and tender lymph gland
enlargement in the neck area.
Measles rash is a reddish,
slightly raised that first
appears on the face and neck
areas.
Mumps
It is transmitted mainly by
infected saliva. This typically
causes enlargement of one or
more of the salivary glands.
These glands are located on
either side of the face, below
the ears. The main symptoms
are severe swelling and
soreness of the cheeks and
jaw.
Process of injecting a person with a dead or weakened virus
which stimulates the immune system to build cells that
destroy the invader cell upon next entry
DPT: Diphtheria, Pertussis (Whooping cough) & Tetanus
Rubeola (Measles)
MMR: Combined Measles, Mumps and Rubella
Polio
Pneumococcal pneumonia
Hemophilus meningitis
Hepatitis B
Rotavirus
Foldable (First Side)
• Virus- Infectious agent • A host is required for
made up of a core of
replication.
nucleic acid and
• Host- organism which
protein coat.
shelters or nourishes
• Not a living organism,
something by
it must have a host.
providing materials
necessary for viral
replication.
Foldable (Second Side)
• Viral Structure• Composed of three
parts.
1. capsid- protective coat
around core
2. nucleic core
3. Envelope- Layer
which surrounds the
capsid.
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Viral Infections
Influenza- flu
Rabies
Chicken Pox
Polio
Measles and Mumps
Thank goodness for
vaccines!