Carol A Phillips

The ecology, epidemiology and virulence of Enterococcus.

Enterococci are Gram-positive, catalase-negative, non-spore-forming, facultative anaerobic bacteria, which usually inhabit the alimentary tract of humans in addition to being isolated from environmental and animal sources. They are able to survive a range of stresses and hostile environments, including those of extreme temperature (5-65 degrees C), pH (4.5-10.0) and high NaCl concentration, enabling them to colonize a wide range of niches. Virulence factors of enterococci include the extracellular protein Esp and aggregation substances (Agg), both of which aid in colonization of the host. The nosocomial pathogenicity of enterococci has emerged in recent years, as well as increasing resistance to glycopeptide antibiotics. Understanding the ecology, epidemiology and virulence of Enterococcus species is important for limiting urinary tract infections, hepatobiliary sepsis, endocarditis, surgical wound infection, bacteraemia and neonatal sepsis, and also stemming the further development of antibiotic resistance.

The effect of lemon, orange and bergamot essential oils and their components on the survival of Campylobacter jejuni, Escherichia coli O157, Listeria monocytogenes, Bacillus cereus and Staphylococcus aureus in vitro and in food systems

Aims:  To investigate the effectiveness of oils and vapours of lemon (Citrus limon), sweet orange (Citrus sinensis) and bergamot (Citrus bergamia) and their components against a number of common foodborne pathogens.

Vapour phase: a potential future use for essential oils as antimicrobials?

Essential oil (EO) vapours have been known for their antimicrobial properties since the 4th century B.C.; however, it was not until the early 1960s that research into the potential of these volatile oils was explored. More recently, the use of EOs such as tea tree, bergamot, lavender and eucalyptus in vapour form has been shown to have antimicrobial effects against both bacteria and fungi, with range of methods being developed for dispersal and efficacy testing. To date, many applications for EO vapours as antimicrobials have been identified including in the food and clinical arenas.

The epidemiology, detection and control of Escherichia coli O157

Numbers of cases of human infections caused by Escherichia coli O157 have increased over the last decade in many countries. As well as the typical symptoms of gastrointestinal illness, the organism can cause more life-threatening diseases such as haemorrhagic colitis and haemolytic uraemic syndrome (HUS). Although the incidence remains relatively low compared with the other foodborne pathogens such as Campylobacter and Salmonella, the mortality rate associated with infection is much higher. Cattle are thought to be the main environmental source of this organism, and most cases have been associated with consumption of beef and beef products. However, other food vehicles have been identified, such as apple cider and raw or unpasteurised milk and milk products. Cross-contamination has been shown to be an important factor in outbreaks, which, together with the fact that the infectious dose is low (as few as 10 cells), means that robust hygienic procedures are essential at all stages of the food chain to reduce risk of infection. Person-to-person spread is a common source of illness, and several laboratory-acquired cases have also occurred. Efficient detection, isolation and confirmation techniques are required to establish the reservoirs of this organism in the environment and its spread into, and within, the food chain. This article reviews the epidemiology of E coli O157 and discusses detection and preventative methods, both developed and developing. © 1999 Society of Chemical Industry

The survival of three strains of Arcobacter butzleri in the presence of lemon, orange and bergamot essential oils and their components in vitro and on food

Aims:  To test the effect of oils and vapours of lemon, sweet orange and bergamot and their components against three Arcobacter butzleri strains.

The mechanism of action of a citrus oil blend against Enterococcus faecium and Enterococcus faecalis.

Aims:  The aim was to explore the mechanisms by which a blend of orange (Citrus sinensis) :  bergamot (Citrus bergamia) (1 : 1 v/v) EO (essential oil) (2% v/v) and its vapour (15 mg l−1 air) brings about its antimicrobial effect against Enterococcus faecium and Enterococcus faecalis.

The anti-biofilm activity of lemongrass (Cymbopogon flexuosus) and grapefruit (Citrus paradisi) essential oils against five strains of Staphylococcus aureus

To determine the sensitivity of five strains of Staphylococcus aureus to five essential oils (EOs) and to investigate the anti‐biofilm activity of lemongrass and grapefruit EOs.

Classification Systems for Hallux Rigidus: A Review of the Literature

Background Hallux rigidus (HR) is one of the most common causes of forefoot pain. A number of classification systems have been developed to evaluate HR. These systems are based on either radiological parameters alone or a combination of radiological and clinical features. The purpose of this paper is to critically evaluate HR classification systems by undertaking a detailed review using English language medical and paramedical databases. Materials and Methods The authors identified 18 formal HR classification systems described in the literature, some of which are variations on a theme. Results No clear consensus on the construction of HR classification systems appears to exist. Different criteria and methods are used which make comparison difficult. Furthermore, it appears that, no serious consideration has been given to their reliability and validity. Criteria used to justify inclusion of these parameters have been based mainly on clinical experience rather than formal research. Conclusion For such a common condition, there is a need for a properly constructed, prospective study to develop a suitable classification system. It should include scientifically validated parameters to help stratify different stages of the disease and aid clinical and scientific communication.

The effect of citric acid, lactic acid, sodium citrate and sodium lactate, alone and in combination with nisin, on the growth of Arcobacter butzleri

The importance of Arcobacter spp. as a cause of human foodborne illness is unresolved. Organic acids and their sodium salts, and nisin are preservatives commonly used in the type of foods from which the organism is recovered. In this study their effect on the growth of A. butzleri in culture, alone and in combination, was investigated. At 0·5%, 1·0% and 2·0% lactic and citric acids inhibited A. butzleri growth; 2% sodium lactate was effective in inhibiting growth over 8 h incubation but not over longer periods. Sodium citrate was more effective than sodium lactate. Nisin alone inhibited A. butzleri growth at 500 IU ml−1 over 5 h. It did not enhance the effect of sodium citrate inhibition but it did augment the effect of sodium lactate alone over 8 h.

Arcobacters as emerging human foodborne pathogens

Abstract Arcobacter spp. are increasingly being isolated from a wide range of foods especially those of animal origin, such as pork and poultry, and products derived from these. Although its role in the disease process remains to be fully elucidated, there have been several reports of the organism being implicated in human illness. This article reviews the procedures that have been developed for the isolation and identification of Arcobacter spp. which have lead to its detection in a wide range of animals and foods and discusses the role that this organism may have in the epidemiology of foodborne disease.