Antibiotic Resistance

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Antibiotic Resistance

• The Challenge in a Changing World

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The Scene Maddy is sick. Poor little girl seems
to have some sort of upper respiratory illness.
She is taken into the doctor who wants to be
extra sure this cute little girl gets better.
Just to make sure he hasnt misdiagnosed her he
gives her an antibiotic, even though he is pretty
sure it is a virus and just needs to run its
course.
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Here is the issue . . . She takes an antibiotic .
. . Methicillin for example. It kills off 99.99
of the bacteria . . . But what about that other
0.01?
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It still survives and begins to reproduce like
before except this time with no competition. As
it undergoes binary fission it passes on its new
resistant gene . . .
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And now what happens if she really needs
antibiotics? We must use an even stronger
antibiotic. And who is to say that will work
completely? It is a never ending game that we
have created. Are we prepared for it?
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Staphylococcus aureus

• Frequently living on skin or in your nose
• 20-30 of people are Staph carriers
• Causes more than 500,000 hospitalized Staph
  infections in U.S. each year
• Usually treated with Methicillin

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MRSA Methicillin-resistant S. aureus

• It has evolved, and continues to do so
• Requires strong antibiotics like vancomycin IV
  only!
• Almost always spread through direct physical
  contact
• often in hospitals

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How do bacteria become resistant?

• How do antibiotics work?
• Stop or interfere the cellular processes that
  bacteria depend on to survive
• Crippling the production of the bacterial cell
  wall.
• Interfering with protein synthesis
• Blocking the synthesis (production or making) of
  DNA and RNA.

• Bacteria come up with ways to counter or fight
  these actions of the antibiotics
• Changing the permeability of its cell membrane
  and therefore the antibiotic cannot be taken up
  by the cell at all.
• 2. Changing molecules inside themselves and in
  doing so confusing the
• antibiotic so the antibiotic misses the target.
• 3. Destroying the antibiotic. Some bacteria
  produce enzymes that chew up penicillin.

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Non-drug resistant bacteria can get or acquire
resistance by getting a copy of a gene that
fights antibiotics from another drug resistant
bacteria!
The result.
http//www.fda.gov/AnimalVeterinary/SafetyHealth/A
ntimicrobialResistance/ucm134359.htm
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What led to antibiotic resistance?
Added to food
Overuse of antibiotics
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SUPERBUG - VRSA

• VRSA Vancomycin-resistant S. aureus

What is next? Can we keep up?
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The other factor here is, as a society, becoming
aware and not overprescribing antibiotics.
Also, not prescribing too many combination
antibiotics. Good Luck!!!