Lyrics · 完整歌詞
Antimicrobial resistance emerges and spreads through genetic variation, gene transfer and selection,
rather than a purposeful response by individual organisms.
Every large bacterial population contains a few organisms carrying resistance genes,
which grow slowly under that burden.
A broad-spectrum antibiotic clears their susceptible neighbours and empties the niche,
so the resistant few inherit the whole space.
Hospitals breed resistant organisms because three conditions coincide: the highest antibiotic density,
the weakest hosts and the most invasive devices.
Reducing unnecessary selection pressure and interrupting transmission are therefore central to control,
alongside effective diagnostics, appropriate treatment and the development of new therapies.
Carbapenem-resistant Acinetobacter baumannii illustrates the mechanism.
It stacks an OXA-type carbapenemase,
loss of outer membrane porins and active efflux pumps,
so it usually resists almost every other class as well.
Moreover, it tolerates dryness and survives for weeks on bed rails,
keyboards and ventilator screens.
Environmental cleaning and contact precautions therefore matter as much as any antibiotic.
MRSA resists through an altered target, PBP2a encoded by mecA,
so beta-lactamase inhibitors achieve nothing.
Community strains carry Panton-Valentine leukocidin and cause abscesses
and necrotising pneumonia in the young.
Among carbapenem-resistant Enterobacterales, KPC is a serine enzyme, whereas NDM,
IMP and VIM are zinc-dependent metallo-beta-lactamases that clavulanate cannot inhibit.
Antimicrobial resistance emerges and spreads through genetic variation, gene transfer and selection,
rather than a purposeful response by individual organisms.
Antimicrobial stewardship asks four questions: the right drug, the right dose,
de-escalation and duration.
Prospective audit with feedback and pre-authorisation are its principal tools.
Healthcare-associated infection follows one structure, a device, a duration and a host.
Central line, catheter and ventilator each bypass a natural barrier,
and organisms ascending them lay down a biofilm.
Within that film metabolism slows,
antibiotics penetrate poorly and immune cells cannot enter,
so the cure is removal rather than escalation.
Every bundle ends with daily assessment of necessity,
and each infection is defined after more than two days of device exposure.
Central line insertion demands hand hygiene, maximal sterile barriers,
chlorhexidine skin preparation and avoidance of the femoral site,
with hub disinfection thereafter.
Urinary catheters are inserted only for clear indications,
drained in a closed system kept below the bladder
and never on the floor.
Ventilated patients are nursed at thirty to forty-five degrees with daily sedation interruption,
chlorhexidine mouth care and subglottic drainage.
Surgical prophylaxis is given within sixty minutes before incision,
hair is clipped rather than shaved, and glucose and temperature are controlled.
Hand hygiene has five moments arranged by causation.
Before touching a patient and before an aseptic procedure protect the patient.
After body fluid exposure,
after touching the patient
and after touching the surroundings protect the next patient and the worker.
Alcohol rub fails on soiled hands and after Clostridioides difficile.
Isolation is layered on standard precautions.
Contact applies to MRSA, Acinetobacter and difficile,
and droplet with surgical masks to influenza, pertussis and meningococcus.
Airborne isolation with negative pressure and N95 respirators is reserved for tuberculosis,
measles and varicella.
The 2003 SARS epidemic taught that isolation must separate rather than aggregate,
leaving behind fever screening, patient flow design and the TOCC history.
Antimicrobial resistance emerges and spreads through genetic variation, gene transfer and selection,
rather than a purposeful response by individual organisms.