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Following an inquest into the deaths of 3 people from the Legionella bacteria, it may now become compulsory for results of cooling towers to be made available to health officials.

According to Canterbury’s medical officer of health, Alistair Humphrey who told an inquest looking into three deaths from legionella in winter 2005 says that New Zealand should adopt a compulsory regime on testing and reporting of legionnaire’s disease.

All 3 deaths were part of an outbreak of 19 cases clustered in the southwest of Christchurch, Dr Humphrey told Southland-Central Otago coroner Trevor Savage at the inquest, which is likely to last two days.

“It is appropriate that New Zealand moves to adopt a compulsory regime,” Dr Humphrey said. “It will in my view minimise the risk of another outbreak and will be likely to save lives.”

Attention has centred on the cooling tower at the Ravensdown plant in the suburb of Hornby as a possible source, and the company had lawyer Robert Osborne at today’s hearing.

He asked about gaps in the testing of cooling towers, and reporting of results under the present voluntary regime, and Dr Humphrey agreed it was possible that none of the cases came from the Ravensdown cooling tower.

But Dr Humphrey also said: “Our view is that there is no way you can say none of them came from that point source. Everything pointed to a cluster in the southwest of Christchurch around the plant we are talking about, with what we found to be genetically identical species of legionella.”

He agreed with Mr Osborne that the strain was the ubiquitous Christchurch type of the disease.

Inquiries by health officials during the outbreak turned up 141 cooling towers. Some of the owners or those leasing the buildings had not co-operated by testing and providing results and had to be visited by officials.

It meant there were gaps in the knowledge of what was happening during the April to August outbreak. When tests were done it was not known how many had already used biocide to kill organisms in the cooling systems — a call made by health officials to contain the outbreak.

The inquest is hearing evidence on the deaths of Ross Hern 56, Peter Jones, 48, and Valmai Finlayson, 87, who died of legionnaire’s disease at Christchurch Hospital.

Legionella species are widely found in lakes, rivers, groundwater and soil. The hearing was told it was “generally benign” until it was turned into a mist and spread. This could be through hot water systems, air cooling systems, cooling towers, water spraying devices, water sprinklers, demisters, and spa pools. An Auckland outbreak had been traced to a high pressure hose used in a boat washing operation.

When Ravensdown tested its tower in April, it was found to have a high level of 2400 colony-forming units of legionella. Biocide was used and a later test showed the level was down to 260 units.

Ravensdown provided its results to the health authorities.

Dr Humphrey suggested four changes were needed to tighten testing and reporting procedures for legionella, consistent with requirements in New South Wales, Victoria, and now being considered by South Australia.

He wants local bodies to maintain a register of cooling towers, evaporation condensers, and scrubbing towers. In the 2005 outbreak it took health officials about two weeks to gather information on all these installations from Christchurch City Council records.

He also wants compulsory testing by owners and operators, and compulsory disclosure of the results to local authorities and medical authorities.

He also wants a consistent testing regime between commercial and industrial properties.

Giving evidence this afternoon, a senior technical adviser to the Department of Building and Housing, Bruce Trevor Klein, told the coroner that since 2004 all new buildings with water cooling towers required a building compliance certificate.

Owners were required to test their systems regularly for bacterial organisms.

Cooling towers under the 2004 Act had to be sited away from building air conditioning intake systems.

Building owners must furnish annual documents showing the cooling towers had been tested monthly for legionella bacteria.

Legislation required owners or operators of cooling towers showing a level of legionella bacteria exceeding 1000 colony-forming units (cfus) should notify a medical officer of health within 48 hours.

Test results had to be retained for two years.

Questioned by Mr Savage, Mr Klein said his department would need to investigate whether it would support the mandatory reporting of all water cooler test results to health authorities.

He cautioned against Canterbury Medical Officer of Health Alister Humphrey’s earlier assertion that New Zealand should adopt Australia’s reporting system.

Mr Klein said he understood the Ministry of Health was investigating adopting a system that would require the mandatory reporting of high legionella bacterial counts.

As the law stood now, building owners, cooling tower operators and laboratories had no onus to make such reports available despite having to test regularly and retain results.

Questioned by Donna Blandford, niece of the late Mr Hern, Mr Klein said under the Building Act, cooling tower owners or operators faced fines of up to $200,000 for non-compliance.

He was unaware of any prosecutions.

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The Food and Drug Administration (FDA) and the USDA have extended GRAS (Generally Recognised as Safe) Approval for LISTEXâ„¢ to all Food Products.

In the fight against Listeria, one of the most dangerous food pathogens, US food processing companies can now apply a novel yet natural tool: LISTEXâ„¢ bacteriophages. The FDA and USDA have approved this
product from The Netherlands as GRAS, based on extensive safety and efficacy data and organoleptics tests confirming that LISTEXâ„¢ is safe and has no impact on taste, smell, colour, and other physical properties of treated products.

Bacteriophages or phage are some of the most abundant micro-organisms on earth. Fresh water and seawater can contain as many as 1 billion phages per ml, while in fresh and processed meat and meat products, more than 100 million viable phages per gram are often present. Phages are harmless to humans, animals and plants, and target only bacterial cells. They are extremely specific in regard to the bacteria they recognize.

The LISTEXâ„¢ bacteriophages target only Listeria bacteria (leaving desirable bacteria in place), and are easy to apply in the environmental areas of the production processes or even within the process.

In October 2006 the FDA had already proclaimed GRAS for LISTEXâ„¢ against Listeria in cheese. The extension to all products susceptible to Listeria, opens the door for the meat and fish industry to apply LISTEXâ„¢.

Earlier this month, the Dutch designated inspection office SKAL confirmed the ‘organic’ status of LISTEX™ under EU law, as a result of which it can be used in the EU in regular and organic products.

EBI Food Safety’s CEO, Mark Offerhaus: “Food Safety now tops the agenda of US food processing companies and consumers, who are insisting on ‘green’ solutions, rather than chemicals. Natural bacteriophages prove to be a unique solution, where increased safety does not come at the expense of product characteristics. US food processors can now benefit from LISTEX™, like their European counterparts.”

According to the World Health Organization (WHO), Listeriosis, the disease caused by Listeria monocytogenes, is one of the most severe food borne infections, with a mortality rate of 30%. It can take weeks after exposure before an infection becomes apparent. The US Food Safety and Inspection Service maintain a zero tolerance policy for the bacterium, which grows at refrigeration temperature and is omnipresent.

Researchers from the University of Sheffield have received joint funding from the Engineering and Physical Science Research Council (EPSRC) and the Ministry of Defence (MoD) to develop an innovative sensor to detect bacteria. The new method will use a polymer which will give a fluorescent signal when it encounters bacteria, allowing scientists to easily identify infected wounds much earlier than using conventional methodologies.

The new technology will be of immediate benefit to healthcare industries in general, as well as those involved in detecting infection in battlefield conditions and bacterial contamination, whether accidental or deliberate.

Currently identifying bacterial infection takes several days and requires swabbing and culturing of bacterial swabs as well as the use of specialist bacteriology laboratory facilities.

By combining polymers, which change shape when they encounter bacteria, and developing a light signal through fluorescence non radiative energy transfer (NRET), the researchers will be able to detect early stages of bacterial contamination.

Being developed by a multi-disciplinary team of researchers from the University’s Departments of Chemistry, Engineering Materials and the Dental School, the sensor will have widespread applications beyond the initial project.

Dr Steve Rimmer from the University’s Department of Chemistry, said: “The project is a great example of progress that can be achieved at the life sciences/physical sciences interface and we hope the project will deliver technology of real importance.”

The multi-disciplinary team will be led by Dr Steve Rimmer of the Department of Chemistry and consists of Dr Linda Swanson (Chemistry) Professor Sheila MacNeil (Engineering Materials) and Dr Ian Douglas (Clinical Dentistry).

The project received £670,000 funding jointly from the Engineering and Physical Science Research Council and the Defence Science and Technology Laboratory – an agency of the Ministry of Defence over three years and started in December 2006.

Pink slime at the surface of water trickling through an old mine in California is proving to be a haven for researchers in their quest to learn more about how bacterial communities co-exist in nature.

A letter published in Nature shows that it is possible to follow what micro-organisms are doing in their natural environment by identifying the range of proteins that they produce. The technique, utilized in a microbial community thriving in battery acid-like streams underground at Richmond Mine near Redding, California, combines recently developed ways to sequence microbial genes with methods to identify the range of proteins from specific microbial members.

Researchers from Oak Ridge National Laboratory and UC Berkeley discovered that Leptosprillium group II bacteria in these streams are exchanging large blocks of genes. While scientists have seen extensive gene transfer in bacteria, this is the first observation of exchange of huge genomic blocks in a natural microbial community.

“Consequently, this provides important information about the conservation of genetic resources to enable life to survive and thrive,” said ORNL’s Bob Hettich, a co-author and member of the Chemical Sciences Division. “Ultimately, the basic knowledge gained from this research will lead to a greater understanding of genetic diversity in related organisms and should lead to developments in human health
and bioremediation.”

The combination of mass spectrometry support from ORNL researchers with extensive reconstruction of genomes from community genomic data at UC Berkeley was a key component to this work, said Jill Banfield, who led the project. Banfield, a professor in UC Berkeley’s Department of Environmental Science, Policy and Management, expects this to have far reaching implications.

“More important perhaps is the demonstration of our ability to simultaneously identify a large fraction of an organism’s proteins and to distinguish them from proteins derived from quite closely related organisms,” Banfield said. “This opens the way for detailed studies of how a wide range of microbial communities are structured and how they function.” Hettich agreed that today’s powerful molecular tools are playing a vital role in investigating the complexity of how bacterial consortia cooperate and compete in nature. In fact,
ORNL mass spectrometry provided the ability to resolve and differentiate peptides that differ by as little as one amino acid.

Nathan VerBerkmoes of the lab’s Chemical Sciences Division was instrumental in designing the experiments and acquiring the mass spectrometry data while Manesh Shah of the Biosciences Division provided the bioinformatics horsepower to sort through the massive datasets.

“A key aspect of this paper is the ability to get proteome information on organisms that do not directly have complete genome sequencing information,” VerBerkmoes said. “As a result we could study organisms related to those completely sequenced – such as the bacterial clades, or ‘cousins,’ that are likely to exist in natural environments”.

“This also might have implications into helping study human proteomics because not everyone’s individual genome will be sequenced.”

The pink microbial biofilm communities found in the mine runoff provide perfect research specimens because they have fewer organisms than most communities found in nature. The reason, Hettich noted, is that these environmental conditions – a low pH of 0.8 are way too extreme for most organisms to survive. A pH level of 7 is considered neutral and most proteins prefer pH levels between 5 and 7. In addition, the water from the mine often exceeds 120 degrees Fahrenheit. Because of their simpler makeup, the Banfield Laboratory established these communities as a model system in the mid 90s.

This latest publication builds upon research that was published in May 2005 by Science. In that paper, Banfield, Hettich and colleagues at ORNL describe the bacteria community that thrives in what amounts to sulphuric acid. Their work set the stage for the latest development because it provided the first large-scale proteome dataset for a real life microbial community with a limited number of members.

Of particular interest to DOE is how this effort relates to its Genomes to Life program, which is focused on identifying and characterizing the molecular machines of life. This study helps extend the initial studies of microbial isolates growth in carefully controlled laboratory settings to more real-world complicated microbial communities.

Funding for this project, which is in the second of five years, is provided by DOE’s Office of Science, Office of Biological and Environmental Research and by the National Science Foundation. UT-Battelle manages ORNL for DOE.

Did you know that Information on responses of higher organisms to climate change is dominated by events in spring. Far less is known about autumnal events and virtually nothing about communities of microorganisms.

The autumnal fruiting patterns of macrofungi over the past 56 years were analysed and results indicated the average first fruiting date of 315 species is earlier compared to the last fruiting date.

Fruiting of mycorrhizal species that associate with both deciduous and coniferous trees is delayed in deciduous, but not in coniferous, forests. Many species are now fruiting twice a year, indicating increased mycelial activity and possibly greater decay rates in ecosystems.

Science. 2007 Apr 6;316(5821):71.
Gange AC, Gange EG, Sparks TH, Boddy L
School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK. a.gange@rhul.ac.uk

Over the past twenty years, the rapid emergence and increased prevalence of opportunistic Gram-negative bacilli demonstrating resistance to the β-lactam class of antibiotics has become a major health care crisis.

The production of β-lactamases, the innate capabilities of these organisms to genetically adapt structural and regulatory genes and the ease with which resistance genes are transferred via plasmids, transposons and integrons between different species, have broadened the ability of Gram-negative bacteria to inactivate the β-lactam antibiotics. This diminishes the clinical utility of these key anti-microbial agents making them resistant.

Extended spectrum β-lactamases (ESβLs) hydrolyse the penicillins, first-, second- and third-generation cephalosporins, especially cefotaxime, ceftriaxone, ceftazidime and cefpodoxime, and the oxyimino-monobactam, aztreonam.

ESβLs are inhibited by β-lactamase inhibitors, such as clavulanic acid, and are susceptible to the carbapenems (imipenem, meropenem and ertapenem) and the cephamycins (cefoxitin and cefotetan), though there have been a number of reports stating that ESβL-producing organisms can become resistant to the cephamycins due to the loss of an outer membrane porin protein (Martinéz-Martinéz et al 1996).

Since their discovery following the clinical introduction of the third-generation oxyimino-cephalosporins in 1981, there are now approximately 160 Temoneira (TEM), 100 sulfhydryl-variable (SHV), 64 cefotaxime-hydrolysing (CTX-M) and 102 oxacillinase (OXA) variant enzymes, along with a number of minor ESβL variants (Jacoby and Bush 2007).

Extensive laboratory and clinical experience exists regarding the detection and treatment of ESβL-producing Gram-negative bacilli. This suggest that the knowledge of their existence via means of antibiotic selective pressure, adaption and dissemination, may have an impact on therapeutic choices and the health and well-being of patients via targeted pragmatic antimicrobial selection and infection control practices.

It is unclear; however, if ESβL-producing organisms are being accurately detected 100% of the time. Furthermore, with the recent emergence of metallo β-lactamase-producing Gram-negative bacilli, it is also unclear whether the same mandate exists for the accurate detection, treatment and control of metallo β-lactamases. Metallo β-lactamases (MβLs) are a therapeutic disaster.

These enzymes hydrolyse all β-lactam antibiotics (except the monobactams), including the “drugs of last resort” the carbapenems (imipenem and meropenem), thus requiring the use of alternative, potentially more toxic classes of antibiotics to circumvent the hydrolytic actions of these β-lactamases.

Metallo β-lactamases, which are found in organisms such as Pseudomonas aeruginosa, Acinetobacter specie and members of the Enterobactericeae group such as salmonella and especially Escherichia coli and Klebsiella pneumoniae. They all utilise metal ions (usually zinc) to coordinate water molecules that serve as nucleophiles and hydrolyse the amide bond of the β-lactam ring, rendering the β-lactam antibiotic inactive.

These enzymes are divided into four genetically mobile variants: the older imipenem-hydrolysing (IMP) and Verona integron-encoded metallo β-lactamase (VIM) enzymes; and the more recently described Sao Paolo metallo β-lactamase (SPM) and GIM types (Poirel et al 2004).

Gram-negative bacteria that produce extended-spectrum and metallo β-lactamases are being discovered and isolated at a significant rate worldwide, while the development of new synthetic and natural antimicrobial agents to combat and elude the hydrolytic actions of these β-lactamases has significantly decreased in recent years (Valenzuela et al 2004).

Clinicians prescribing antibiotics need to know, understand and appreciate the short and long term outcomes of the inappropriate use of antibiotics for their patients, which, if not controlled and decreased, will inevitably reduce or eliminate the therapeutic options available in the future.

References

Franklin, C., Liolios, L., Peleg, A.Y. (2006). Phenotypic detection of carbapenem-susceptible metallo β-lactamase-producing Gram-negative bacilli in the clinical laboratory. Journal of Clinical Microbiology, 44: 3139-3144.

Martinéz-Martinéz, L., Hernández-Allés, S., Albertí, S., Tomás, J., Benedi, V., Jacoby,G.A. (1996). In vivo selection of porin-deficient mutants of Klebsiella pneumoniae with increased resistance to cefoxitin and expanded-spectrum cephalosporins. Antimicrobial Agents and Chemotherapy, 40, pp. 342-348.

Poirel, L., Heritier, C., Spicq, C., Nordmann, P. (2004). In vivo acquisition of high-level resistance to imipenem in Escherichia coli. Journal of Clinical Microbiology, 42 (8), pp. 3831-3833.

Valenzuela, J., Thomas, L., Iredell, J. for Australian Society of Microbiology (ASM). (2004). Beta-lactam resistance in Gram-negative bacteria. Antimicrobial Susceptibility Testing: Methods and Practices with an Australian Perspective, 5, pp. 127-157.

Bacteria in the world’s oceans can efficiently exploit solar energy to grow, thanks to a unique light-capturing pigment. This discovery was made by researchers at University of Kalmar in Sweden, in collaboration with researchers in Gothenburg, Sweden, and Spain. The findings are described in journal Nature.

It was long thought that algae were the only organisms in the seas that could use sunlight to grow,” says Jarone Pinhassi, a researcher in Marine Microbiology at Kalmar University College. These microscopic algae carry out the same process as green plants on land, namely, photosynthesis with the help of chlorophyll.

In 2000 scientists in the U.S. found for the first time that many marine bacteria have a gene in their DNA that code for a new type of light-capturing pigment: proteorhodopsin.

Proteorhodopsin is related to the pigment in the retina that enables humans to see colours. It should be possible for this pigment to enable marine bacteria to capture solar light to generate energy, but until now it had not been possible to confirm this hypothesis.

Last year researchers from Kalmar collected 20 marine bacteria from different ocean areas and mapped their genomes. Several of them proved to contain the pigment proteorhodopsin. This made it possible to run a series of experiments that clearly show that growth in bacteria with this pigment is stimulated by sunlight, because the pigment converts solar energy to energy for growth. In other words, the scientists had found a new type of bacterial photosynthesis that takes place in the seas.

It’s easier to understand the importance of understanding new mechanisms in marine bacteria to making efficient use of solar energy if we consider the fact that one litre of natural sea water contains roughly a billion bacteria. The activity of these bacteria is of great importance to the carbon cycle, through, for example, the amount of carbon dioxide they produce, and also to how the solar energy that reaches the earth is channelled through the nutrition cycle.

“Bacteria in the surface water of the world’s oceans swim in a sea of light,” says Jarone Pinhassi. “And it is shouldn’t be too surprising that evolution has favoured micro-organisms that can use this rich source of energy. This type of protein may also play a role in commercial and environmental perspectives, for the development of artificial photosynthesis for the environmentally friendly production of energy.”

According to Reuters (BERLIN), there was an outbreak of salmonella in Germany. This outbreak has infected more than 250 people and has already killed two people.

This outbreak resembles similar occurrences in the Australian salmonella outbreak (Broughton House) which claimed five lives.

The Klinikum Fulda, a 924-bed hospital in the town of Fulda in central Germany, said 233 patients and staff had been infected by the outbreak, along with a further 23 people in a nursing home attached to the institution.

Achim Hellinger, the hospital’s medical director, said the precise cause of the outbreak had not yet been identified, but that the risk of it reaching the general public was negligible.

“The risks of the salmonella infection being spread from person to person are extremely small,” he said, adding that measures to contain the bacteria had been put in place.

Most of those infected were not seriously affected by the bacteria, which usually stemmed from infected food, he added.

The hospital said two women over the age of 80 had died as a direct result of infection, one of them in the nursing home. The death of another woman in her seventies was indirectly linked to the salmonella, it added.

Of those infected at the hospital, 145 were patients and 88 were employees, the Klinikum Fulda said in a statement.

An outbreak was first logged at the hospital in late April, since when the number of reported infections has risen steadily.

Salmonella bacteria are frequently responsible for food-borne illnesses and may cause vomiting, abdominal pains and bouts of fever in those who ingest it.

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Enterobacter sakazakii is a gram-negative non spore forming rod within the family Enterobacteriaceae, genus Enterobacter. The genus Enterobacter is also part of the coliform group.

The organism was originally called “yellow-pigmented Enterobacter cloacae” until the 1980’s when it was renamed Enterobacter sakazakii. Urmenyi and Franklin reported the first two known cases of meningitis caused by Enterobacter sakazakii in 1961. Since then, further cases of meningitis, septicemia, and necrotizing enterocolitis due to Enterobacter sakazakii have been reported around the world. Although the majority of documented cases involve infants, reports also describe infections within adults.

Overall, the fatality rates have varied considerably and although rare, as high as 80 percent in some instances have been reported. While a reservoir for Enterobacter sakazakii is unknown, a growing number of reports suggest a role for powdered milk-based infant formulas as a vehicle for infection.

Due to further risk assessments, there is very little known about virulence factors and pathogenicity of Enterobacter sakazakii. However concerns are present and some powdered ingredients are now considered a risk if it is added to products for infants and the elderly to consume. They include whey powder, cheese powder, starches, vitamins and so forth.

It looks like this could be an up and coming pathogen in 2007 and it won’t be long before the regulators start to include this bacterium into their list of “pathogens of concerns”.

According to the Leader, Health Authorities were quite about the number of buildings in St George being tested for Legionnaire’s disease.

Air-conditioning cooling towers were being examined in the Kogarah and Rockdale municipalities after two residents contracted the infection.

A man in his early 40s and a woman in her 70s are being treated for the illness in St George Hospital.

The woman was in a serious but stable condition on Monday. The man was listed as being stable.

Legionnaire’s is an infection of the lungs (pneumonia) caused by Legionella bacteria.

It can live in water sources including some air-conditioning systems. The disease can occur when people have breathed in mist from a contaminated cooling tower. The South Eastern Sydney and Illawarra Area Health Service expect to have results of the tests today.

Its public health unit has also been piecing together where the patients had been during the incubation period.

The pair was believed to have contracted the disease between the last week of March and the first week of April.

They were admitted to hospital last week.

Director of Public Health Mark Ferson said local emergency departments, GPs, pathology laboratories and chest and infectious diseases physicians had been warned to be on the lookout for any patients with pneumonia-like symptoms and to test for legionella.

”There have been two cases confirmed and, while this is not an unusually high number, both cases had onset dates around the same time and the patients all live in and frequent the same geographical area,” Professor Ferson said.

”As part of the investigation and response we are working with local council officers.”

Majority of people recover from the illness, however some can become very ill with pneumonia and may die.

A medical epidemiologist from the Public Health Unit, Philippa Binns, would not confirm which buildings had been tested, or how many.
She would also not be drawn on information received by the Leader that the male patient is an employee of a licensed premise in Kogarah which the female patient was believed to have visited.

”The point we do want to make is that people need to be aware of the symptoms and, if concerned, should go to a doctor to get assessed,” Dr Binns said.

Dr Binns said there tended to be more cases at this time of year when the temperature varied and cooling systems were turned off and on.

Councils are required to carry out regular maintenance and testing of cooling towers.

A spokesman for Rockdale Council said the outbreak was not in its area.

A spokesman for Kogarah Council said that there were 12 cooling towers in building towers in its municipality.

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