Transcript Vaccinations

Viruses, Bacteria &
Protists…oh MY!
http://labtutorials.org/category/animation/
Disease causing agents that activate the immune system
Vaccinations
Activate our acquired immune system
Cause creation of memory cells
Prevent us from showing symptoms of
disease even if we are exposed to it
Prevent us from transmitting disease to
others
Can eradicate disease causing agents
from the face of the earth!
Smallpox virus
wiped off the face of the earth, except for
samples held in labs in the U. S. & Russia
 Smallpox was an entirely human disease -- it didn't infect any
other animal or insect on the planet. Thus, once vaccination
eliminated the chances of the virus spreading among the
human population, the disease disappeared; in fact, the
United States hasn't vaccinated for smallpox since 1972.
 Although smallpox was one of the most devastating illnesses
in human history, killing more than 300 million people
worldwide during the 20th century alone, scientists declared
the world free of smallpox in 1979. The naturally occurring
disease has been eradicated, but fears remain about the
smallpox samples being used as bioweapons.
 1 OR 2 PEOPLE IN 1 MILLION WHO RECEIVE THE VACCINE MAY DIE AS A
RESULT BECAUSE THIS IS A LIVE VACCINE OF A POX VACCINE SIMILAR
TO SMALL POX (.000000002 %)
How we make vaccinations
Viruses are identified & isolated from host
Host cells must be found in which viruses can
reproduce ( eggs, tissue culture)
Viruses are injected into host cells, millions of
viruses are produced.
Viruses are isolated from host cells/purified
Viruses are either killed or weakened
http://content.time.com/time/video/player/0,3206
8,60312463001_1951560,00.html
Live Attenuated vaccinations
living microbes weakened = no symptoms.
closest thing to a natural infection, so elicit
strong cellular & antibody responses
often confer lifelong immunity
The remote possibility that an attenuated
microbe could mutate back to a virulent form
Viruses attenuated by growing them in cells in
which they do not reproduce very well.
As they evolve to adapt to the new environment,
they become weaker with respect to their natural
host, human beings.
Inactivated Vaccinations
Produced by killing the microbe with chemicals,
heat, or radiation.
More stable
Dead microbes can’t mutate back to diseasecausing state
Most stimulate a weaker immune system
response
So need booster shots
Subunit Vaccines
include only antigen parts of microbe
Some only epitopes.
Much lower chances of adverse reactions
Scientists ID antigens that activate immunity
They grow microbes & use chemicals to break
them apart and gather the important antigens.
Antigens multiplies by recombinant DNA tech.
Scientists inserted hepatitis B antigen genes
into common baker’s yeast. The yeast then
produced the antigens, which scientists purified
for use in the vaccine.
Toxoid Vaccines
For bacteria that secrete toxins as the main
cause of illness.
Scientists inactivate toxins by treating them with
formalin
 Such “detoxified” toxins, called toxoids, are in
vaccines.
The immune system produces antibodies that
lock onto and block the toxin.
Vaccines against diphtheria and tetanus are
toxoid vaccines.
Flue shot:
 Inactivated flue virus
Different infectious agents
 http://www.susanahalpine.com/anim/KubyHTML/vaccine.htm
Overview of humoral immune
response
 http://www.historyofvaccines.org/content/how-vaccines-work
 Between 1990 and 1995 in the UK, there were 5433
suspected adverse reactions to all the vaccines given to
children under 15 years of age - out of around 80 million
doses of vaccine - that's 0.00008% of cases. Only a tiny
number of those were serious.