Bacterial Resistance to Antibiotics

Antibiotics Natural substances that attack metabolic pathways in bacteria (not in the host) –Immobilize or destroy bacteria –ex. penicillin Produced by mold (pencillium notatum) prevents bacteria from building a normal cell wall Review: What do we know about antibiotics and viruses?

Since 1940’s “Age of Antibiotics” – more than 2500 naturally occurring antibiotics identified Over past 50 years, many disease-causing bacteria slowly developed ‘resistance’ How does ‘resistance’ happen?

Variation

Variation cont’d… Bacterial populations have variation When first exposed to antibiotic…weak strains of bacteria are killed –Other members with slight variation in genetic material survive –These individuals reproduce and pass on genes

Why is this a problem? Some bacteria can resist up to 7 separate antibiotics Drug resistant strains claim lives everyday –Over-use / over-prescription is a major problem today

Which antibiotics should be used to combat this bacterial infection?

Remember… Always use all doses, do not save unused antibiotics for later infections Antibiotics destroy helpful bacteria as well –Prolonged use can have side-effects