Skip to main content Skip to Search Box

Definition: MRSA from Collins English Dictionary

abbreviation for

1 methicillin-resistant Staphylococcus aureus: a bacterium that enters the skin through open wounds to cause septicaemia and is extremely resistant to most antibiotics. It has been responsible for outbreaks of untreatable infections among patients in hospitals

Summary Article: MRSA
From The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide

Abbreviation for methicillin-resistant Staphylococcusaureus, a bacterial strain that causes serious problems in hospitals.

While ordinary Staphylococcus aureus are widespread and can cause illnesses from wound infections through to toxic shock syndrome, they generally respond to standard antibiotics such as penicillin. MRSA, by contrast, which was first discovered in the UK in 1961, has acquired a gene known as mecA, making it resistant towards methicillin and a range of other antibiotics from the penicillin family.

The UK government introduced a mandatory MRSA surveillance system in 2001. In its first four years (2001–05), the annual numbers of recorded MRSA infections were between 7,200 and 7,700. Data from death certificates in England and Wales show that the number of deaths attributed directly to MRSA peaked at just over 500 in 2006. By 2008 it had dropped by more than 50%.

MRSA spread dramatically in the 1990s. In the UK, the proportion of S. aureus samples tested positive for methicillin resistance rose from 2% in 1990 to a peak of 43% in 2002. Concerns over this development led to the reconsideration of hospital hygiene routines and the responsible use of antibiotics.

It has been estimated that more than 50 million people carry MRSA (2007), most of them without suffering any symptoms. In hospitals, patients with a compromised immune system, open wounds, or catheters, are particularly at risk of developing a symptomatic MRSA infection. While there are no definitive figures on mortality or morbidity, it is generally thought that MRSA infection represents a significant additional risk to vulnerable patients. MRSA normally responds to two antibiotics (vancomycin and teicoplanin) which are considered too toxic for use in any but life-threatening infections, but it still causes fatalities.

Complete genome sequences of MRSA and of a methicillin-sensitive strain were reported in 2004.


Antibiotic Resistance: A Rising Toll

© RM, 2018. All rights reserved.

Related Articles

Full text Article MRSA
Merriam-Webster's Medical Dictionary

any of several strains of a bacterium (Staphylococcus aureus) that are resistant to methicillin and related antibiotics (such as penicillin) and oft

Full text Article MRSA
Dictionary of Microbiology & Molecular Biology

Methicillin-resistant Staphylococcus aureus . Resistance to methicillin is generally accompanied by resistance to other β-lactam antibiotics,...

Full text Article Methicillin-Resistant Staphylococcus Aureus (MRSA)
Gale Encyclopedia of Nursing and Allied Health

Definition Methicillin-resistant Staphylococcus aureus (MRSA) infections are caused by a strain of the staphylococcus bacterium that often does n

See more from Credo