MRSA was first isolated in NZ in 1975, remained at extremely low levels over the next 10 years (0.05% of 2077 surveyed Staphylococcus aureus isolates nationally in 1982). But from the 1990’s onwards the incidence of various strains of MRSA has steadily increased in both hospitals, rest homes and the community.
Most of us carry Staph aureus as part of our normal skin flora. When we have a cut, wound or other compromised skin integrity (e.g. infected dermatitis/eczema) some of our normal flora can increase in numbers to cause what we recognise as a clinical infection.
i.e. we catch this Staph aureus infection from our own normal flora
Community laboratory data now shows that 5 out of every 100 Staph aureus infections in the South Island, 12 out of every 100 in the Auckland region, are now MRSA
i.e. MRSA is now endemic in the population, so trying to isolate those with MRSA or remove it from those who are carriers by ‘decolonisation’ (e.g. chlorhexidine body washes and mupiricin) is a wasted effort, and can in fact be counterproductive – toxicity, promotes antibiotic resistance, stigmatisation, isolating residents is generally shown to produce worse clinical outcomes. Isolation is required for some infectious diseases which MRSA is not.
Resident/patient with MRSA – use good Standard Precautions (hand hygiene). Cover any infected cuts or wounds as per normal. Plus Contact Precautions (glove/gown) as you normally would if providing wound care and splashing or direct skin or uniform contact possible.
Staff member with MRSA – again no special precautions are generally required and ‘decolonisation’ is not indicated. Good Standard Precautions (hand hygiene – alcohol hand rubs or liquid soap and water both work well).
We should always aim to prevent any cross infections of any organisms, susceptible or resistant.
Good ongoing environmental and equipment cleaning and hygiene should be maintained routinely in the facility, regardless of any known MRSA or other resistant organisms (e.g. ESBL).
- Our total combined use of antibiotics has bred or created these resistant bacteria – are we doing all we can to reduce any over use of antibiotics? g. UTI’s are commonly ‘over treated’ on a positive dipstick result rather than clear clinical symptoms
- Any known positive MRSA (or ESBL) only represents the tip of the iceberg – a known positive person is an indicator only of a much larger issue, there will be many more unknowns. So, like blood and body fluids, it is best to think any one of us – staff residents and patients – could be positive at any time because we not uncommonly will be but seldom be aware of it
- MRSA, ESBL, VRE carriers – the good news is 9 times out of 10 we spontaneously lose our carriage or colonisation of these resistant bacteria in 1-12 months when we happen to be carriers and do not use antimicrobials, and usually we will not know when we are carriers, but temporary carriage is likely on staff several times over in a 5-10 year period
- ESBL (extended spectrum beta lactamase) is increasing similarly to MRSA, but started a few years later. Its primary reservoir source is the bowel not the skin
- Staph aureus itself (the susceptible form MSSA and the more resistant form MRSA) generally have equal pathogenic potential but are generally normal flora also
- Each one of us is made up of 10 trillion tissue cells and 90 trillion bacteria e. ‘your bugs are my bugs’ – we cannot but help share our microbes by touch, shedding skin, etc but we must actively reduce this sharing by good Standard Precautions on all by all
Our combined total use of antibiotics continues to create ever more microbial resistance.
Good hand hygiene and cough containment Standard Precaution practice coupled with thorough cleaning of equipment and the environment will ensure there is a lower risk of transmission and environmental contamination of our shared microbes – the resistant and susceptible forms.
Article shared with the kind permission of:
Author: Ben Harris – Microbiologist – Southern Community Laboratories (2015)