Staph and MRSA Infection: An Overview

Staphylococcus aureus is a human pathogen, appearing under the microscope as a sphere or cluster. Gram positive or purple in colour, staph is encased in a wall of protection. This tiny but powerful microbe is responsible for many internal and external tissue infections, from superficial wound infection to life threatening bacteraemia (infection in the blood). Staph can spread easily through contact with people or objects that carry the Staphylococcus aureus bacteria. It does not require an opening in the skin to colonise another person.

Staph lives naturally in up to a third of people, often not causing any trouble at all, however for the ageing population and those with reduced immunity, fighting a staph infection can be serious.

Identification of MRSA infection

When a staph infection is identified, it is cultured by a lab to verify if it is sensitive to antibiotic treatment or resistant. Can antibiotic treatment permeate the wall of protection? If not, treatment must be tailored and is generally complex. Resistant staph is Methicillin resistant Staphylococcus aureus or MRSA, the antibiotic resistant form of staph. MRSA has mutated into what is commonly referred to as a ‘superbug’ or a multidrug resistant organism (MRO).

The good news—MRSA infections are preventable and can be curbed. In the US, the Veterans Affairs Medical Centres saw a 55% reduction of MRSA between 2005–17 using simple but effective strategies: an emphasis on hand hygiene, contact precautions for those with MRSA, and the tracking of MRSA infection. 

The not so good news—MRSA infections continue to be a leading cause of healthcare associated infection, particularly in aged care.

The CDC have categorised MRSA as a serious threat within their National Action Plan for Combating Antibiotic Resistant Bacteria (2020-2025). It is estimated, MRSA is responsible for 1.7 billion (US dollars) in attributed health care spending.

The Study

A retrospective study on MRSA recently released by the Journal of the American Board of Family Medicine, titledMethicillin-Resistant Staphylococcus Aureus Colonization and Mortality Risk Among Community Adults Aged 40-85 bolsters the need for effective strategies to reduce MRSA. The study utilised a community cohort, with data accessed from the National Death Index. Using a multistage sample method, the results are intended to be representative of the US population.

The findings: over an 11-year period, 18% mortality for non-colonised participants and 36% for MRSA-colonised participants. The mortality rates for MRSA colonised participants were approximately 50% higher than non-colonised participants.

MRSA colonization in middle-aged and older adults in the community is associated with a significantly increased mortality risk. S. aureus colonization is not associated with increased mortality, which is consistent with previous research

The study notes a few basic limitations, one being the uncertainty of the length of time each participant had MRSA.

For the full report visit https://pubmed.ncbi.nlm.nih.gov/33833016/

MRSA is a significant threat to aged care facilities in Australia and New Zealand. As with many things infection prevention and control, it is easier to prevent the spread than it is to treat the infection. The best approach to MRSA is ensuring that it isn’t spread within residential aged care facilities through appropriate and thorough infection control policies.

Bug Control’s eManual is a digital resource that gives your facility the tools it needs to prevent MRSA infections, as well as deal with any outbreaks in aged care. It has been developed especially for aged care facilities, tailored for both Australia and New Zealand. Why wouldn’t you want the best for your facility?

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