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B D Cookson

Publications and source records attributed to B D Cookson.

At least 19 recordsLinked to original sources
PubMed2006

Status of infection control policies and organisation in European hospitals, 2001: the ARPAC study.

Patient safety in hospital care depends on effective infection control (IC) programmes. The Antimicrobial Resistance Prevention and Control (ARPAC) study assessed the organisation, components and human resources of IC programmes in European hospitals. A questionnaire survey of policies and procedures implemented in 2001 for the surveillance and control of nosocomial infection and antibiotic resistance was completed by 169 acute-care hospitals from 32 European countries, categorised by five geographical regions. A formal IC programme existed in 72% of hospitals, and a multidisciplinary IC committee was operational in 90%. Trained IC nurses (ICNs) were present in 80% of hospitals (ranging from 54% in south-east and central-eastern Europe, to 100% in northern Europe), whereas 74% had one or more trained IC doctors (ICDs) (ranging from 46% in south-east Europe to 84% in western Europe). Median staffing levels were 2.33 ICNs/1,000 beds and 0.94 ICDs/1,000 beds. The intensity of IC programmes scored higher in centres from northern and western Europe than from other European regions. Written guidelines promoted hand hygiene for healthcare workers in 89% of hospitals, education in 85%, and audit in 46%. Guidelines recommended use of alcohol-based solutions (70%) and/or medicated/antiseptic soap (43%) for decontamination of non-soiled hands. Use of alcohol-based solutions varied according to region, from 41% in southern Europe to 100% in northern Europe, compared with use of medicated soap from 77% in southern Europe to 11% in northern Europe (p < 0.01). These findings showed that IC programmes in European hospitals suffer from major deficiencies in human resources and policies. Staffing levels for ICNs were below recommended standards in the majority of hospitals. Education programmes were incomplete and often not supported by audit of performance. Hand hygiene procedures were sub-standard in one-third of centres. Strengthening of IC policies in European hospitals should be a public health priority.

Cross Infection↗
PubMed2005

Guidelines for the control of glycopeptide-resistant enterococci in hospitals.

The increase since the mid 1980s in glycopeptide resistant enterococci (GRE) raised concerns about the limited options for antimicrobial therapy, the implications for ever-increasing numbers of immunocompromised hospitalised patients, and fuelled fears, now realised, for the transfer of glycopeptide resistance to more pathogenic bacteria, such as Staphylococcus aureus. These issues underlined the need for guidelines for the emergence and control of GRE in the hospital setting. This Hospital Infection Society (HIS) and Infection Control Nurses Association (ICNA) working party report reviews the literature relating to GRE prevention and control. It provides guidance on microbiological investigation, treatment and management, including antimicrobial prescribing and infection control measures. Evidence identified to support recommendations has been categorized. A risk assessment approach is recommended and areas for research and development identified.

Anti-Bacterial Agents↗
PubMed2005

Staphylococcus aureus isolates carrying Panton-Valentine leucocidin genes in England and Wales: frequency, characterization, and association with clinical disease.

Staphylococcus aureus isolates carrying the genes that encode for Panton-Valentine leucocidin (PVL), a highly potent toxin, have been responsible for recent outbreaks of severe invasive disease in previously healthy children and adults in the United States of America and Europe. To determine the frequency of PVL-positive isolates sent to the Staphylococcus Reference Unit (United Kingdom) for epidemiological purposes, we tested 515 isolates of S. aureus, and 8 (1.6%) were positive for the PVL locus. A further 470 isolates were selected to explore the association of PVL-positive S. aureus with clinical disease. Of these, 23 (4.9%) were PVL positive and most were associated with skin and soft tissue infections (especially abscesses). The PVL genes were also detected in isolates responsible for community-acquired pneumonia, burn infections, bacteremia, and scalded skin syndrome. Genotyping by pulsed-field gel electrophoresis and multilocus sequence typing revealed that the PVL-positive isolates were from diverse genetic backgrounds, although one prevalent clone of 12 geographically dispersed methicillin-resistant S. aureus (MRSA) isolates was identified (ST80). All 12 isolates were stapylococcal cassette chromosome mec type IVc, had an agr3 allele, and shared a common toxin gene profile (sea-see, seg-sej, eta, etb, and tst negative but etd positive). ST80 strains with similar genetic characteristics have been responsible for community-acquired infections in France and Switzerland. The remaining PVL-positive isolates were mostly methicillin-sensitive S. aureus and belonged to 12 different sequence types, including ST22 and ST30, which are closely related to the most prevalent MRSA clones in United Kingdom hospitals, EMRSA-15 and EMRSA-16, respectively.

Bacterial Toxins↗
PubMed2004

Isolation measures in the hospital management of methicillin resistant Staphylococcus aureus (MRSA): systematic review of the literature.

OBJECTIVE: To evaluate the evidence for the effectiveness of isolation measures in reducing the incidence of methicillin resistant Staphylococcus aureus (MRSA) colonisation and infection in hospital inpatients. DESIGN: Systematic review of published articles. DATA SOURCES: Medline, Embase, CINAHL, Cochrane Library, System for Information on Grey Literature in Europe (SIGLE), and citation lists (1966-2000). REVIEW METHODS: Articles reporting MRSA related outcomes and describing an isolation policy were selected. No quality restrictions were imposed on studies using isolation wards or nurse cohorting. Other studies were included if they were prospective or employed planned comparisons of retrospective data. RESULTS: 46 studies were accepted; 18 used isolation wards, nine used nurse cohorting, and 19 used other isolation policies. Most were interrupted time series, with few planned formal prospective studies. All but one reported multiple interventions. Consideration of potential confounders, measures to prevent bias, and appropriate statistical analysis were mostly lacking. No conclusions could be drawn in a third of studies. Most others provided evidence consistent with a reduction of MRSA acquisition. Six long interrupted time series provided the strongest evidence. Four of these provided evidence that intensive control measures including patient isolation were effective in controlling MRSA. In two others, isolation wards failed to prevent endemic MRSA. CONCLUSION: Major methodological weaknesses and inadequate reporting in published research mean that many plausible alternative explanations for reductions in MRSA acquisition associated with interventions cannot be excluded. No well designed studies exist that allow the role of isolation measures alone to be assessed. None the less, there is evidence that concerted efforts that include isolation can reduce MRSA even in endemic settings. Current isolation measures recommended in national guidelines should continue to be applied until further research establishes otherwise.

Cross Infection↗
PubMed2004

Methicillin-resistant Staphylococcus aureus in hospitals and the community: stealth dynamics and control catastrophes.

Methicillin-resistant Staphylococcus aureus (MRSA) represents a serious threat to the health of hospitalized patients. Attempts to reduce the spread of MRSA have largely depended on hospital hygiene and patient isolation. These measures have met with mixed success: although some countries have almost eliminated MRSA or remained largely free of the organism, others have seen substantial increases despite rigorous control policies. We use a mathematical model to show how these increases can be explained by considering both hospital and community reservoirs of MRSA colonization. We show how the timing of the intervention, the level of resource provision, and chance combine to determine whether control measures succeed or fail. We find that even control measures able to repeatedly prevent sustained outbreaks in the short-term can result in long-term control failure resulting from gradual increases in the community reservoir. If resources do not scale with MRSA prevalence, isolation policies can fail "catastrophically."

Community-Acquired Infections↗
PubMed2004

The community prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in older people living in their own homes: implications for treatment, screening and surveillance in the UK.

Methicillin-resistant Staphylococcus aureus (MRSA) predominantly affects those over 65 years old. There may be a substantial pool of older people with MRSA in the community. We studied the prevalence in one London general practice, screening 258 older people living in their own home. MRSA (E-MRSA 15) was found in two participants (0.78%). Past history of MRSA was the only significant risk factor. The results of this and other studies suggest that national guidelines recommending early discharge for MRSA carriers have not resulted in widespread community acquisition amongst elderly people living in their own home. Community antibiotic policies for skin and soft-tissue infection do not require amendment. Patients with previous MRSA should be isolated and screened on admission especially to high-risk units.

Age Distribution↗
PubMed2004

Emergence, spread, and characterization of phage variants of epidemic methicillin-resistant Staphylococcus aureus 16 in England and Wales.

Epidemic methicillin-resistant Staphylococcus aureus 16 (EMRSA-16) and EMRSA-15 are the two most important and prevalent EMRSA strains found in the United Kingdom and have also been found in a number of European countries and the United States. We describe for the first time the spread of an EMRSA strain (EMRSA-16) from its point of origin in one hospital to the surrounding hospitals and regions over the following 2 years. In the first 18 months after its original appearance, 136 hospitals referred EMRSA-16 isolates for typing, and interhospital and intraregional spread were reported: it was more prevalent in males between 60 and 80 years old and was isolated from sputum and throat more often than EMRSA-15. Important characteristics, e.g., carriage of the enterotoxin A (sea) and toxic shock syndrome toxin (tst) genes and production of urease, are described. Phage-variant strains of EMRSA-16 which share some of the characteristics of the classical strain, including toxin carriage and urease production, emerged, but without genotypic investigations, their relationship could only be inferred. A total of 129 clinical isolates from 52 hospitals, collected between March 1998 and April 1999 and representing classical EMRSA-16 (49 isolates) or phage variants (80 isolates), were compared by phage typing, pulsed-field gel electrophoresis (PFGE) following SmaI macrorestriction, antimicrobial susceptibility testing, urease production, and PCR detection of toxin gene carriage. PFGE analysis revealed 29 profiles, A1 to A29, with A1 representing the prototypic strain, NCTC 13143. All other profiles differed from A1 by 1 to 6 bands, but some differed from each other by up to 10 bands.

Anti-Bacterial Agents↗
PubMed2003

Systematic review of isolation policies in the hospital management of methicillin-resistant Staphylococcus aureus: a review of the literature with epidemiological and economic modelling.

OBJECTIVE: To review the evidence for the effectiveness of different isolation policies and screening practices in reducing the incidence of methicillin-resistant Staphylococcus aureus (MRSA) colonisation and infection in hospital in-patients. To develop transmission models to study the effectiveness and cost-effectiveness of isolation policies in controlling MRSA. DATA SOURCES: MEDLINE, EMBASE, CINAHL, The Cochrane Library and SIGLE (1966-2000). Hand-searching key journals. No language restrictions. REVIEW METHODS: Key data were extracted from articles reporting MRSA-related outcomes and describing an isolation policy in a hospital with epidemic or endemic MRSA. No quality restrictions were imposed on studies using isolation wards (IW) or nurse cohorting (NC). Other studies were included if they were prospective or employed planned comparisons of retrospective data. Stochastic and deterministic models investigated long-term transmission dynamics, studying the effect of a fixed capacity IW, producing economic evaluations using local cost data. RESULTS: A total of 46 studies were accepted: 18 IWs, 9 NC, 19 other isolation policies. Most were interrupted time series, with few planned formal prospective studies. All but one reported multiple interventions. Consideration of potential confounders, measures to prevent bias, and appropriate statistical analysis were mostly lacking. No conclusions could be drawn in a third of studies. Most others provided evidence consistent with reduction of MRSA acquisition. Six long interrupted time series provided the strongest evidence. Four of these provided evidence that intensive control measures which included patient isolation were effective in controlling MRSA. In two others IW use failed to prevent endemic MRSA. There was no robust economic evaluation. Models showed that improving the detection rate or ensuring adequate isolation capacity reduced endemic levels, with substantial savings achievable. CONCLUSIONS: Major methodological weaknesses and inadequate reporting in published research mean that many plausible alternative explanations for reductions in MRSA acquisition associated with interventions cannot be excluded. No well-designed studies allow the role of isolation measures alone to be assessed. Nonetheless, there is evidence that concerted efforts that include isolation can reduce MRSA even when endemic. Little evidence was found to suggest that current isolation measures recommended in the UK are ineffective, and these should continue to be applied until further research establishes otherwise. The studies with the strongest evidence, together with the results of the modelling, provide testable hypotheses for future research. Guidelines to facilitate design of future research are produced.

Cost-Benefit Analysis↗
PubMed2001

Children with atopic dermatitis who carry toxin-positive Staphylococcus aureus strains have an expansion of blood CD5- B lymphocytes without an increase in disease severity.

Toxin-positive strains of Staphylococcus aureus (T + S. aureus) are present on the skin of some but not all patients with atopic dermatitis. Many staphylococcal toxins are superantigens, which can stimulate the immune response and thus may potentially lead to the very high levels of IgE characteristic of this condition, as well as exacerbating the clinical disease. The aim of this study was to determine whether the presence of T + S. aureus on the skin of children with atopic dermatitis was associated with in vivo evidence of a heightened humoral immune response, higher IgE levels and more severe clinical disease. Toxin gene expression in S. aureus isolated from the eczematous lesions of 28 children with atopic dermatitis was assessed by PCR. Clinical and immune data were also collected from this cohort. Thirteen of the 28 children (46%) were colonized with T + S. aureus strains. The presence of T + S. aureus was associated with a significant expansion in peripheral blood CD5- B cells (P = 0.01), and the more toxin types identified the greater the B-cell expansion (P = 0.002). However, in this cohort of children with atopic dermatitis, despite th in vivo expansion of B cells in children harbouring T + S. aureus, there was no associated increase in IgE levels or in clinical disease severity scores.

Adolescent↗
PubMed2001

Diploma in Hospital Infection Control: a progress report.

The Diploma in Hospital Infection Control (DipHIC) was established by the Hospital Infection Society (HIS), the London School of Hygiene and Tropical Medicine (LSHTM) and the Public Health Laboratory Service (PHLS) in 1997 and has now completed two examinations. We outline progress since the announcement of the diploma and changes to the written examination and reflective portfolio. The reflective process is described and guidance provided to active infection control practitioners wishing to consider application for the diploma by accreditation of prior learning.

Certification↗
PubMed2000

Do antimicrobials have a role in preventing septicaemia following instrumentation of the urinary tract?

Urinary tract instrumentation is a significant cause of septicaemia. Review of the literature suggests that selective use of antimicrobials would reduce the risk of septicaemia as this varies between patients and with procedures. Antimicrobial prophylaxis is indicated for patients at high risk of endocarditis, or who are neutropenic. For patients without these risk factors, it is indicated for open, transurethral, or certain forms of laser prostatectomy or trans-rectal prostate biopsy. For cystoscopy, antimicrobials are indicated for patients with preoperative bacteriuria or a preoperative indwelling catheter. Single dose aminoglycosides or oral fluoroquinolones are the agents of choice with the exception of the prevention of endocarditis, where combinations active against streptococci are recommended. For other instrumentations, the risk of antimicrobial toxicity probably outweighs the benefits and a risk-reduction strategy is recommended. Further studies are required to provide definitive answers in many of these areas.

Adult↗
PubMed2000

Methicillin-resistant Staphylococcus aureus in the community: new battlefronts, or are the battles lost?

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of nosocomial infections worldwide. Interpretation of community MRSA trends is problematical, in that the term is ill-defined, and related data are difficult to put into context. There are four relevant battlefronts, all of interest to risk assessment and prevention. These comprise the following: the issues relating to an increasing pool of patients with MRSA discharged from hospitals into the community; MRSA spreading to patients in nursing and residential homes; and MRSA spreading from patients and healthcare workers to others in the community. There are often difficulties in determining whether the fourth issue, MRSA arising apparently de novo in the community, is in fact due to one of these other fronts. All these battlefronts are important and not yet lost. However, we must agree on definitions and design-appropriate surveillance strategies, so that we can best inform prevention and control activities to contain these emerged or emerging problems.

Community-Acquired Infections↗