INFECTION CONTROL
In order to introduce effective
infection control measures, the basic epidemiology of an infection (route of
transmission, host risk factors, etc.) must be considered. the incidence and
nature of a HAI (as with any infection)depend on the:
• organism;
• host (patients and staff);
• environment
The
organism
the organisms responsible for common nosocomial infection may be acquired endogenously or exogenously.
Endogenous infection
An infectious agent that is already present in the host causes
endogenous infection. the infectious agent is usually part of the normal host flora.Antibiotics and exposure to the hospital environment can change the normal flora of the host and may select for resistant organisms. Risk of infection may be reduced by protecting any potential sites of entry, e.g.
intravascular lines.
Exogenous infection
When the infectious agent originates from outside of the host.
the pathogen is usually acquired from the environment by various routes,
including: airborne, direct contact, or percutaneous routes. Within the
hospital setting, environmental infection is usually due to a contaminated item of equipment and can be minimized by implementing the correct decontamination,
sterilization, and infection control procedures. Cross-infection (or transmission) refers to infection acquired in hospital from another person, either patients or staff. Risks can be reduced by focusing on measures to interrupt transmission, e.g. handwashing.
Organisms commonly involved in HAIs
Infection |
Organism(s) involved |
UtIs |
Gram-negative bacteria, e.g. E.
coli, Proteus spp., |
Respiratory infections |
Bacteria, e.g. H. influenzae, S.
pneumoniae, P. aeruginosa, |
Wounds and skin |
Bacteria, e.g. S. aureus, S. pyogenes,
anaerobes |
BSI |
Gram-positive bacteria, e.g. S.
aureus, including MRSA, |
GI infections |
Bacteria, e.g. C. difficile |
Viruses, e.g. norovirus |
The
host
Patient risk factors that result in increased likelihood of
acquiring an infection in hospital include:
• severity of the
underlying acute illness and patient co-morbidities.
Severely ill patients are more vulnerable to acquiring an infection and
more likely to have a worse outcome;
• use of medical
devices—these breach host defences and provide
possible portals of entry for organisms;
• extremes of age—the
elderly and very young are at higher risk;
• immunosuppression.
Staff
risk factors include:
• immunosuppression, e.g.
HIV; pregnancy;
• staff who perform
exposure-prone procedures are more likely to be
exposed to blood-borne viral infections;
• skin conditions (e.g.
eczema) increase prolonged carriage of organisms
such as MRSA.
The
environment
the hospital environment includes all of the physical
surroundings of the
hospital patients and staff, i.e. the building, fittings, fixtures,
furnishings,
equipment, and supplies. the following are important environmental issues
in the control of infection:
• environmental cleaning
(see Box 6.5);
• environmental
disinfection;
• decontamination of
equipment;
• building and
refurbishment, including air-handling systems;
• clinical waste
management;
• pest control;
• food services/food
hygiene;
• isolation
facilities/ability to cohort patients.
Routes
of transmission
the isolation precautions required depend on the likely route of
transmission of the organism. the main routes are:
• airborne—this is when
the infection usually occurs by the respiratory
route, with the agent being carried in aerosols (<5 micrometres in diameter);
• droplet—large droplets
carry the infectious agent (>5 micrometres in diameter);
• direct
contact—infection occurs through direct contact between the source of infection
and the recipient, i.e. person-to-person spread;
• indirect
contact—infection occurs through ‘indirect contact’, i.e. via
equipment contaminated with body fluids such as urine, faeces, and
wound exudates. this route also includes contact via an environmental
source, e.g. an outbreak of gastroenteritis transmitted by food;
• inoculation—infection
occurs through direct inoculation, e.g. needlestick
injury. Other routes include via blood products (hepatitis A, Yersinia
enterocolitica, Serratia), total
parenteral nutrition (tPN), and other fluids
(Enterobacter, B. cepacia, Bacillus cereus). Multidose vials should be avoided.
Hospital cleaning
‘Dirty hospitals’ are frequently reported by the media, with
attention drawn to the lack of investment and poor support for hospital cleaning. Providing a clean and safe environment for health care is a key priority for the NHS and is a core standard in Standards
for better health. Other publications, such as Towards cleaner
hospitals and lower rates of infection,
have further emphasized this and recognize the role of cleaning in minimizing
HAIs by the physical removal of dirt, fomites, dust, and human body fluids. In 2007, the National Patient Safety Agency produced guidelines
for cleaning (The national
specifications for cleanliness in the NHS: a framework for setting and measuring performance outcomes). the results of PeAt (Patient environment Action team) assessments are calculated against these specifications.
Handwashing
the importance of handwashing has been recognized since the
nineteenth century when Semmelweiss encouraged medical students in Vienna to wash their hands in chlorinated lime solution on the delivery unit. the maternal mortality rate from puerperal fever in patients attended to by medical students
was far lower than those attended to by midwives who did not wash their hands.
today HCW hand hygiene is a topic of global importance. The WHO produced the
first global patient safety challenge relating to hand hygiene ‘Clean Care is
Safer Care’. the goal of Clean Care is Safer Care is to ensure that infection
control is acknowledged universally as a solid and essential basis towards
patient safety.
Patient
isolation
the use of universal infection control precautions should
minimize the need
for isolation of most patients. In practice, isolation depends on a risk
assessment for each patient, and the side rooms/facilities available in each
trust. Always act on the patient’s clinical presentation, and do not wait for
laboratory results to be available, as it may be too late. Involve your ICt
early, and consult the DH guidance for further advice.effective isolation
relies on all staff following the necessary procedures,to make sure that none
of the transmission barriers are breached. the simplest solution is to use
single rooms, but, in an outbreak, multi-bedded bays,
or even whole wards, may be used.
- CORONA VIRUS
- MONKEY POX
- VAGINAL DRYNESS
- FIBROID
- INFERTILITY
- OVULATION CYCLE
- OVARIAN CANCER
- VAGINAL BACTERIA
- MALE INFERTILITY
- BEST DAYS OF CONCIEVING
- MUCUS AFTER OVULATION
- FOODS FOR ERECTILE FUNCTIONS
- PREGNANCY ANEMIA
- DO AND DONT DURING PREGNANCY
- ERECTILE DYSFUNCTION
- U.T.I IN PREGNANCY
- STROKE RISK
- EAT THIS NOT THAT
- HOOKWORMS INFECTION
- OMEGA 3 BENEFITS
- FASTING
- WEIGHT LOSS TIPS
- vitiligo
- ABORTION
- DENGUE VIRUS
- EBORA VIRUS
- FEVER
- URINARY TRACT INFECTION
- HOSPITAL INFECTIONS
- WEST NILE VIRUS
- YELLOW FEVER
- EYE DISEASE
- ZIKA VIRUS
- STRESS
- IRON DEFFICIENCE
- INSOMNIA (SLEEPING PROBLEMS)
- HEART PROBLEMS
- COMPONENTS OF BLOOD
- BLOOD DISORDER
- LABORATORY TEST OF BLOOD DISORDER
- BONE MARROW EXAMINATION
- BLOOD ANEMIA
- ANIMAL BITES
- EYE BURN
- CHOCKING
- HEAT STROKE
- SMOKE EFFECTS
- SNAKE BITE
- MALARIA VACCINE
- BEST WAY TO SLEEP A CHILD
- CHILD FEVER REDUCING
- ELEPHANTIASIS
- WOMEN BEARDS
- DATES
- PAPAYA FRUITS