Related Experiment Video
Updated: Oct 10, 2025
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
An outbreak of livestock-associated meticillin-resistant Staphylococcus aureus (LA-MRSA) clonal complex 398 in a
M J Stone1, C Swales1, S E Bond2
1Department of Burns and Plastic Surgery, The Mid Yorkshire Hospitals NHS Trust, Wakefield, UK.
Background:
Meticillin-resistant Staphylococcus aureus (MRSA) outbreaks have been reported previously in burns centres with resulting mortality and morbidity. This article describes the first human-associated outbreak in the UK caused by a strain of mupirocin-resistant (MuR) livestock-associated MRSA clonal complex 398 (LA-MRSA CC398) in an adult burns centre. The centre historically had a very low prevalence of MRSA infections.
Aim:
To describe the clinical and epidemiological context of how the outbreak was identified and contained using a range of infection prevention and control (IPC) measures guided by both traditional and genetic methods.
Methods:
A cluster of MuR-MRSA led to an outbreak investigation. Cases were detected via retrospective search and real-time laboratory surveillance. Isolates were sent continuously for whole-genome sequencing (WGS). A live timeline of cases and interventions was produced throughout the period.
Findings:
The outbreak consisted of 12 cases (seven males and five females) aged between 22 and 70 years. Patients were identified between May and October 2020. All patients were colonized rather than infected. The strain acquired the plasmid bearing MupA while colonizing the index case before dissemination. The index case was found to be a chicken farmer. This outbreak was eventually controlled using IPC measures, audits, and blind staff decolonization guided by insight from WGS.
Conclusion:
It was not possible to determine how the strain entered the centre, or if a staff carrier was involved. The outbreak demonstrated the potential for continued transmissions for months despite active surveillance and stringent control measures.
Insights
A UK adult burns centre experienced its first outbreak of mupirocin-resistant livestock-associated MRSA (LA-MRSA CC398). Infection prevention and control measures, guided by whole-genome sequencing, were used to contain the spread of this resistant strain.
Area of Science:
- Infectious Diseases
- Microbiology
- Public Health
Background:
- Meticillin-resistant Staphylococcus aureus (MRSA) outbreaks are a known threat in burns centers.
- This study details the first reported human-associated outbreak in the UK of mupirocin-resistant (MuR) livestock-associated MRSA clonal complex 398 (LA-MRSA CC398) in an adult burns unit.
- The affected center previously had minimal MRSA prevalence.
Purpose of the Study:
- To document the clinical and epidemiological features of a MuR-LA-MRSA CC398 outbreak.
- To describe the identification and containment strategies employed.
- To highlight the role of infection prevention and control (IPC) measures, supported by genetic and traditional methods.
Main Methods:
- An outbreak investigation was initiated following the detection of a cluster of MuR-MRSA cases.
- Case identification utilized retrospective searches and real-time laboratory surveillance.
- Whole-genome sequencing (WGS) was performed on isolates, and a live timeline of cases and interventions was maintained.
Main Results:
- The outbreak involved 12 patients (22-70 years old) identified between May and October 2020, all colonized rather than infected.
- The mupirocin resistance (MupA) plasmid was acquired by the strain during colonization of the index case, a chicken farmer.
- IPC measures, audits, and staff decolonization, informed by WGS, successfully controlled the outbreak.
Conclusions:
- The entry route of the strain and potential staff carrier involvement remain undetermined.
- The outbreak highlighted the potential for prolonged transmission over months, even with active surveillance and strict control measures.
Related Concept Videos
01:26Healthcare Associated Infections I: Iatrogenic, Exogenic and Endogenic
HAIs significantly increase the cost of health care. Extended stays in healthcare institutions, increased disability, increased costs of medications, including specialized antibiotics, and prolonged recovery times add to the patient's expenses and the healthcare institution and funding bodies.
01:20Infection
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...
01:22Healthcare Associated Infections II: Preventive Measures
The best practices for preventing healthcare-associated infections include hand hygiene, patient risk...