6.4 antibiotic resistance

Question 1

what can make bacteria resistant to antibiotics?

Answer 1

mutations during reproduction

Question 2

what mutations can make bacteria resistant?

Answer 2

• make the cell wall impermeable to the drug
• new biochemical pathways
• mutations can switch on genes or create a gene for the profuction of antibiotic-destroying enzymes

Question 3

how could natural selection make bacteria antibiotic-resistant?

Answer 3

• bacteria which are not killed by the antibiotic processes pocess a selective advantage
• this enables them to survive, reproduce and pass on this resistant strain to offspring
• this increases the allelic frequency for resistance in the bacterial population

Question 4

what is an example of a ‘superbug’?

Answer 4

MRSA - a bacteria living on the skin and nasal passages but when it gets into the body, causes boils and infection like septicemia. A mutation enabled some bacteria to produce a penicillinase enzyme to break down penicillin so the infections can only be treated with high doses of antibiotics.

Question 5

what are HCAIS?

Answer 5

Health care associated infections such as Clostridium difficile

Question 6

what is Colostrum difficile?

Answer 6

a bacterium found in the large intestine and is not affected by commonly used antibiotics

Question 7

how can we prevent and control infection?

Answer 7

• only use antibiotics when absolutely nessecary
• all antibiotic courses should be completed
• isolate patients when infected
• screen the patients when they arrive
• limit visitations as they could bring extra infections
• monitor healthcare-associated infections and publish them to raise awareness
• use alcohol based gel to clean
• use chlorine based disinfectant for C.difficile
• wear suitable clothing
• thourough cleaning of toilets and wards