6.4 antibiotic resistance

CREATING DRUG RESISTANT BACTERIA

• antibiotic only effective if microbe has a binding site for the drug and a metabolic process or biochemical pathway the antibiotic can interfere w/

• during bacterial reproduction there’s a chance that a mutation occurs

• some might help microorganism resist the effects of antibiotic

• mutations can result in:

  • making cell wall impermeable to drug

  • new biochemical pathways

  • production of an antibiotic destroying enzyme

• mutations like this will be selected for when an antibiotic is used and bacterial population will become increasingly resistant to the drug. (AS link: Natural Selection)

SUPERBUGS

• widespread use of antibiotics accelerates process of selection of resistance

• as diff antibiotics are used to tackle increasing resistance, this increases selection pressure for evolution of bacteria that are resistant to them all

• this evolutionary race is creating superbugs

  • e.g. MRSA- can cause death in absence of effective antibiotics

SUPERBUGS- PREVENTION

• reduce selection pressure for evolution of resistance in bacteria by using antibiotics sparingly, only when necessary

• complete each course of antibiotics and use as few as possible

• vary the antibiotics used and introduce new ones

HEALTHCARE ASSOCIATED INFECTIONS (HCAIs)

• infections caught while a patient is being treated in hospital

• superbugs common in hospitals because antibiotic use is at its highest

• e.g. MRSA and C. difficile

• HCAIs have a high profile of public awareness and are sometimes referred to as hospital acquired infections

• people more likely to catch infections in hospital because patients have weakened immune systems and are around other ill people

TRANSMITTING HCAIs

• transmitted by poor hygiene, such as:

  • hospital staff and visitors not washing hands before and after visiting a patient

  • coughs and sneezes not being contained

  • equipment (e.g. beds or surgical instruments) and surfaces not being disinfected after used

PREVENTION OF HCAIs

• encourage hospital staff and visitors to wash hands, before and after they’ve been with a patient

• clothing worn by hospital workers should be disposable if possible or washed at high temps if not

• equipment and surfaces should be disinfected after used

• people w/ HCAIs should be moved to an isolation ward so less likely to transmit infection to other patients

ANTIBIOTIC RESISTANT HCAIs

• some HCAIs caused by bacteria that are resistant to antibiotics, e.g. MRSA

• these HCAIs are difficult to treat because antibiotics aren’t effective

• means these HCAIs can lead to serious health problems or even death

• infections caused by antibiotic-resistant bacteria are more common in hospitals (yk why)

PREVENTION AND CONTROL OF ANTIBIOTIC RESISTANT HCAIs

• doctors shouldn’t prescribe antibiotics for minor bacterial or viral infections or prevent infections

• doctors should use narrow-spectrum antibiotics if possible

• doctors should rotate the use of diff antibiotics

• patients should finish course so infections are fully cleared