Hospital acquired infections Flashcards
how many US patients die from HCAIs every day
350
according to the UK national audit office what percentage of patient acquire HAI
9%
what makes hospitals complex environments helpful for pathogenic growth
Water circuits, shower and cooling tower aerosols;
medical and dental water aerosols, patients, staff and visitors: aerosols, touch surfaces
what are Hospital-Acquired (nosocomial) infections
a subset of infectious diseases acquired in a health care facility
To be considered nosocomial, the infection cannot be present at admission; rather, it must develop at least 48 hours after admission.
what are the 3 categories of risk factors for the invasion of colonising pathogens in a hospital
- Iatrogenic risk factors
- Organizational risk factors
- Patient risk factors
what are the iatrogenic risk factors for pathogen invasion in hospitals
– invasive procedures (eg, intubation, indwelling vascular lines, urine catheterization)
– antibiotic use and prophylaxis.
what are the organisation risk factors for pathogen invasion in hospitals
– contaminated air-conditioning systems, water systems
– staffing and physical layout of the facility (eg, nurse-to-patient ratio, open beds close together).
what are the patient risk factors for pathogen invasion in hospitals
– the severity of illness, underlying immunocompromised state, and length of stay.
what surface cleaning problems do hospitals have
– Most surfaces are not smooth - they have draw marks, scratches (etc where pathogens can hide)
– Stainless steel is not easy to clean, as claimed: risk of cross contamination
– Hand hygiene compliance is poor, even among professionals
what is terminal cleaning
environmental cleaning after discharge of a patient
which major antibiotic resistant bacteria is not eradicated by terminal cleaning
MRSA
what percentage of HCAIs are antibiotic resistant
70%
what are the ESKAPE Group of pathogens
six nosocomial pathogens that exhibit multidrug resistance and virulence: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp
what are ESBL bacteria? give examples
A group of bacteria that produce extended spectrum beta-lactamase. ESBL-producing bacteria can’t be killed by many of the antibiotics that doctors use to treat infections, like penicillins and some cephalosporins
( eg Acinetobacter baumannii, E. coli, P. aeruginosa)
give examples of thee superbugs commonly found in hospitals
MRSA (methicillin resistant Staphylococcus aureus)
VRE (vancomycin resistant enterococci)
Clostridium difficile spores
what are the causes of antibiotic resistance
- Over prescribing of antibiotics
- Patients not finishing their treatment
- Over-use of antibiotics in livestock and fish farming
- Poor infection control in hospitals and clinics
- Lack of hygiene and poor sanitation
- Lack of new antibiotics
give examples of when copper has been used to protect human health in the past
Egypt (2000 BC) - Sterilize drinking water and wounds
Greece, Hippocrates (400 BC) – Treat leg ulcers related to varicose veins
Aztecs – Copper oxide and malachite for skin conditions
France (1850 AD) – Copper workers found to be immune during Cholera epidemic
USA, Phildadelphia Hospital Study (1983 AD) – Low E. coli count on brass doorknobs
Punjab, India (2005 AD) – E. coli eliminated in 24 hours in water-filled brass containers (TamraJal used for 5000 years)
why is copper antimicrobial?
it is reactive due to the free electrons in the outer shell, electron transfer reactions can take place (+alterations between redox states). Release of copper ions occurs when microbes are transferred by touching, sneezing or vomiting, land on the copper surface. The ions prevent cell respiration, punch holes in the bacterial cell membrane or disrupt the viral coat, and destroy the DNA and RNA inside. the extremely reactive hydroxyl radical produced in reactions with hydrogen peroxide can also participate.
antimicrobial copper can be used against what water and food borne pathogens
Legionella pneumophila, Helicobacter pylori, E. coli O157
Salmonella, Listeria monocytogenes
what hospital acquired pathogens can antimicrobial copper fight
- MRSA, VRE, C. difficile,
- A. baumannii, K. pneumoniae NDM-1 etc
- Viruses - influenza H1N1, norovirus, adenovirus
- Fungi- Candida, Aspergillus (HVAC systems)
what is MRSA
Methicillin Resistant Staphylococcus aureus “super bug”
A major human pathogen responsible for a range of infections.
Essentially resistant to all β–lactam antibiotics.
why is MRSA resistant to all β–lactam antibiotics
due to the possession of the mecA gene encoding the low-affinity penicillin binding protein.
what drugs are called the ‘antibiotics of last resort’
Carbapenems (eg meropenem)
drugs developed in the evolution of β-lactamase to carbapenamases
- Penicillins
- β-lactamases
- Cephalosporins
- BS β-lactamases
- Cephalosporins e.g. cefoxatime
- for ESBL:- CTX, OXA, TEM
- Carbapenems e.g. meropenem
- for KPC, NDM-1
