Acinetobacter
What is it?
A genus of Gram negative aerobic bacilli divided into 3 main groups: A.baumannii; A.lwoffii; A.haemolyticus.
Where does it live?
Widely distributed in nature, it is an important soil organism which contributes to mineralisation processes. It is able to survive on moist and dry surfaces in the hospital environment and on healthy human skin.
Who is affected?
Debilitated hospital patients particularly in ICU, where it causes late onset ventilator-associated bacteraemia and occasionally Meningitis.
How is it spread?
- Unwashed hands of healthcare workers transferring organisms between patients.
- Hands (often gloved), contaminated during patient care, soil the patient environment where the bacteria persist and can be re-transferred to a new patient.
- Unclean equipment.
How is it controlled?
- Infections can be difficult to treat with antibiotics as multi-resistant strains are common
- Handwashing to the ‘5 moments’ schedule
- Single room isolation
- Thorough environmental cleaning of bed space daily and on discharge
- Closed suction techniques
- Use of care bundle for ventilated patients (HII No. 5 Saving Lives)
- Filters to prevent ventilator contamination
Extended spectrum beta lactamases
What is it?
ESBL – Extended spectrum beta lactamases
- Beta lactamases are enzymes produced by some coliform bacteria that render them resistant to all cephalosporin and penicillin type antibiotics.
- ESBL enzymes are most commonly produced by two bacteria – Escherichia coli and Klebsiella pneumoniae.
Where does it live?
ESBL producing bacteria live:
- In the human gut
- Possibly In the faeces of farm animals
Who is affected?
- A urine infection is the commonest infection caused by ESBL producing bacteria
- ESBL organisms are strongly associated with nursing and care homes and are normally found causing infections of the urine tract
- Patients who are very ill, have catheters, or/and long stay in hospital and those who may have received several courses of antibiotics
How is it spread?
- Person to person via contaminated hands
- Poor practice in urine catheter care
How is it controlled?
- Standard precautions
- Ideally these patients should be isolated
- Standard cleaning procedures
MRSA
What is it?
MRSA stands for meticillin-resistant Staphylococcus aureus – varieties of Staphylococcus aureus that are resistant to meticillin (a type of penicillin) and usually to some of the other antibiotics that are normally used to treat Staphylococcus aureus infections. There are different types of MRSA and laboratory testing can be done to distinguish between them.
Where does it live?
Normal Staphylococcus aureus is present in the nostrils of around 10-30% of healthy people. Like normal Staphylococcus aureus, MRSA is found on the skin but especially in the nose, armpit and groin. If it stays in the nose or on the skin surface it will cause no harm, and this is called colonisation or carriage.
It is not generally necessary to treat MRSA colonisation or carriage. MRSA infection is no more dangerous or virulent than infection with other varieties of Staphylococcus aureus. However some of the antibiotics used to treat MRSA can be more difficult to use or cause more side effects.
Who is affected?
MRSA infections usually occur in hospitals and in particular to vulnerable or debilitated patients, such as patients in intensive care units, and on surgical wards. Some nursing homes have experienced problems with MRSA. MRSA does not normally affect hospital staff or family members (unless they are suffering from a severe skin condition or debilitating disease). In general, healthy people are at a low risk of infection with MRSA.
How is it spread?
MRSA is most commonly spread via hands, equipment, and sometimes the environment. It is important that healthcare workers and visitors wash their hands before and after visiting a patient. Provided hands are not soiled (when they should be washed with soap and water), rapid-acting alcohol hand-rub can be used: it is easier and faster to use than hand washing. Equipment should also be cleaned after use.
How is it controlled?
It is important to understand the difference between colonisation and infection with MRSA. Colonisation is when MRSA is present on or in your body without causing illness whilst infection is when MRSA is making you sick. Suppression of MRSA is used to reduce the amount of MRSA present on an individual to reduce the chance of them developing an infection, for example when they are in hospital. Suppression may include the application of surface antibiotics e.g. to the inside of the nose, and washing with disinfectants.
Although MRSA is resistant to some antibiotics there are others which can be used to treat infections. Vancomycin and Doxycycline are two examples.
Tuberculosis
What is it?
It is an infectious disease caused by bacteria known as Mycobacterium.
Where does it live?
Primarily humans, rarely primates; in some areas diseased cattle, badgers, swine and other mammals are infected
Who is affected?
- The immunosuppressed (people with debilitating disorders e.g. chronic renal failure, some forms of cancer, silicosis, diabetes)
- The risk to children under 3 is higher
- Populations in countries where poverty and lack of hygiene are a problem
- In 2006 in the UK there were over 8,000 cases of TB reported
How is it spread?
The bacteria that cause the disease are inhaled in the form of microscopic droplets that come from a person with tuberculosis. When coughing, speaking and sneezing the small droplets are expelled into the air. They dry out quickly but the bacteria itself can remain airborne for hours. However, the tuberculosis bacteria are killed when exposed to ultraviolet light, including sunlight.
TB usually affects the lungs however other areas may be affected.
How is it controlled?
- Infectious patients may need single room isolation.
- TB is treated with specific antibiotics.
- Individuals who have had contact with TB may be screened to see if they have acquired the infection.
VRE
What is it?
- VRE also known as GRE — Glycopeptide-Resistant Enterococci are enterococci that are resistant to glycopeptide antibiotics (vancomycin and teicoplanin).
Where does it live?
- Enterococci are bacteria that are commonly found in the bowels of most humans
Who is affected?
- Infections caused by GRE mainly occur in hospital patients, particularly those who are immuno-compromised or those in specialist units such as intensive care or renal units. Those who have had previous treatment with certain other antibiotics (particularly cephalosporins and glycopeptides) and those who are on a prolonged hospital stay are also at risk.
How is it spread? - Person-to-person via contaminated hands
- Via contaminated equipment or the environment
How is it controlled?
- Standard precautions
- Ideally patients should be isolated if not possible a risk assessment should be carried out
- Standard cleaning procedures
