The epidemiology of community acquired Methicillin Resistant Staphylococcus aureus (MRSA) and severe community onset sta

Lead Research Organisation: University College London
Department Name: Primary Care and Population Sciences

Abstract

We are trying to find out more about a new type of MRSA infection called community MRSA.
Community MRSA is different from the MRSA that people catch in hospital. It typically affects young and healthy people who have not had contact with healthcare and causes severe infections like boils, abscesses and pneumonia.
We know that community MRSA is a major problem in parts of the USA. In the UK, the number of people admitted to hospital for boils, abscesses and other infections associated with community MRSA has increased dramatically over the last 10 years.
Using a combination of hospital data and new research studies we hope to find out how common community MRSA is in England and Wales. We will look at who gets community MRSA in terms of gender and age and search for factors which might be associated with infection, like taking lots of antibiotics or recent admission to hospital. We will use this information to find out why MRSA is changing and try to explain why more people are being admitted to hospital with boils and abscesses.
We will use this research to support public health measures to control, prevent and treat community MRSA in the future.

Technical Summary

Background

There is international concern about the emergence of community acquired MRSA (C-MRSA) and PVL toxin producing strains of staphylococcus aureus. These organisms can spread in community settings causing severe skin and soft tissue infections and life threatening infections such as staphylococcal pneumonia. Typically they affect healthy children and adults. Although C-MRSA has become an important problem in some parts of the US the size of the problem in the UK is unknown and the epidemiology is poorly described. Over the last decade there has been a marked unexplained increase in hospital admissions for severe staphylococcal infections that could be caused by C-MRSA and/or PVL-positive strains.

Aims and Objectives

This research aims to describe the epidemiology of C-MRSA, investigate the increase in admissions for severe staphylococcal infections and describe the extent to which C-MRSA and PVL-positive strains cause severe boils and abscesses.

Design.

A national case control study of C-MRSA. Case control studies of severe community onset staphylococcal infection. A survey of staphylococcal strains causing severe boils/abscesses.

Methodology.

C-MRSA case control study - Cases: patients with C-MRSA identified via the HPA Staphylococcal Reference Unit. Controls: community controls identified from GP registers. Risk factors will be ascertained by postal questionnaire. The study will identify which groups are at risk for C-MRSA.
Severe staphylococcal infection case control studies. These will be conducted using Hospital Episode Statistics Data and data from the General Practice research Database. They will describe risk factors for severe staphylococcal infection.
Survey of staphylococcal strains causing severe boils/abscess. Clinical teams who routinely submit swabs from drained boils/abscesses will be identified. Microbiologist who identify staphylococcus aurues from these samples will refer organsims to the staphylococcal reference Unit (250 isolates). All organisms will be subjected to a PCR toxin gene detection screen and PCR MecA screen. Methicillin resistant strains will be fully characterised to determine if they are the strain types associated with C-MRSA. The prevalence of PVL-positive strains and C-MRSA strains amongst organisms causing severe boils/abscesses will be described.

Scientific and Medical Opportunities.

MRSA has already become an enormous health issue in hospitals. New strains of toxin-producing MRSA which can spread in the community and cause severe disease in healthy children and adults present a major potential threat to public health. There is a need to understand the extent of the problem and risk factors in order to inform control strategies.

Publications

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