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New Zealand with only a population of 6 million people is a nation of food worriers after a 750 people survey found some interesting data on their views of food and food borne pathogens.

Interestingly, scientists believe people may be anxiously worrying over small issues that pose little risk to their health.

In the phone survey conducted for the New Zealand Food Safety Authority (NZFSA), they found that salmonella was the worst food fear, with 77 per cent being “very concerned” about it.

In addition, an antibiotic in meat was next with 67 per cent and campylobacter with 63 per cent.

But scientist Dr Donald Campbell said people were missing the three biggest threats to life, the amount of salt, fat and sugar in their diet.

Interestingly, people were more concern about eating at local buffets, food halls and ethnic restaurants than food made at home in an unhygienic way.

Campbell, the NZFSA principal adviser of public health, was surprised salmonella was the most feared.

“I would have expected campylobacter to be higher than salmonella,” he said.

Campylobacter had a greater impact on the community than salmonella. There were generally 10 times as many cases of campylobacter in a year than salmonella, said Campbell.

New Zealand had a 15 per cent rise in notified campylobacter cases last year to 15,873, compared with 1335 cases of salmonella.

Both are food-borne illnesses that have been associated with chicken and raw meats, and can cause symptoms of diarrhea, abdominal pain, nausea and headache.

Canterbury medical officer of health Alistair Humphrey put campylobacter high on his list of concerns.

But he said many other bugs lurked in food, including norovirus which causes gastroenteritis’s of which there had been outbreaks in Christchurch.

Antibiotics used in animals for therapeutic purposes and to prevent disease may scare consumers towards vegetarianism, but “the evidence is of it being a very low risk,” Campbell said.

Listeria was a rarer food-borne illness (19 cases nationally last year) but could have devastating consequences, he said. At least half of cases occurred in pregnant women and one in four of their babies have died.

Listeria is linked to deli meats, poultry products, smoked seafood’s, soft cheeses and pre-cooked sausages. However stronger regulations have forced many food manufacturers to comply with strict hygiene.

Participants were more spooked about the use of pesticides in food production and additives.

More than 60 per cent of participants were “very concerned” about their potential effects.

Campbell said these were more “perceived risk” than actual risk, as pesticides and additives were covered by regulations.

The authority commissions the surveys every few years to gauge public feeling and tailor its food safety messages. “We eat at least three times a day, so it matters to us all,” Campbell said.

Genetically modified food greatly concerned 56 per cent of respondents, about the same as in two previous years, whereas a new category, food from cloned animals, worried 54 per cent.

“There is such a small use of genetically modified food. I would not put them as high on the list,” said Campbell.

Food allergies and irradiated food brought up the rear, with 47 per cent and 41 per cent respectively.

A team of scientist have developed a specially tailored viruses could eradicate chronic bacterial infections. When certain bacteria multiply, they produce exo-polysaccharides which lead to biofilms which are nearly impossible to eradicate using conventional antibiotics. Biofilms can be found on medical devices such as catheters.

Boston University biomedical engineers have designed a new, highly effective means of dispersing and killing the bacteria living in biofilms. Led by synthetic biologist James Collins, the team has engineered viruses that attack biofilms on two fronts: by killing the bacteria that live in them, and by dissolving the carbohydrates that hold them together. If such bacteria attacking viruses are proved safe for industrial and clinical use, says Collins, researchers could develop stocks of different kinds of viruses, each tailored to attack a different kind of biofilm.

Collins has designed a virus that can disperse more than 99 percent of the E. coli in a model biofilm. Helen Blackwell a chemist at the University of Wisconsin-Madison, believes that this is an “enormous” achievement: “I haven’t seen anything as effective as this approach.” Collins’s engineered virus is described online in the journal Proceedings of the National Academy of Sciences.

Bacteria living communally in biofilms are one thousand times more resistant to antibiotics than free-swimming bacteria are, says Collins. They are protected by a sticky carbohydrate scaffold called a matrix. The matrix blocks antibiotics and cells from the human immune system, and even provides something like a primitive circulatory system for the bacteria.

In a few cases, including some chronic ear infections in children and chronic lung infections in cystic-fibrosis patients, the tissue harboring a biofilm must simply be cut out. Large doses of antibiotics can usually eradicate these infections, says Blackwell.

But she notes that there is some worry that drug-resistant biofilm infections are becoming more common, and that the use of antibiotics seems to induce biofilm formation.

“One thing I like about Collins’s approach is that it is two-pronged, says Philip Stewart, director of the Center for Biofilm Engineering at Montana State University. “The viruses kill the bacteria, but they also target the biofilm matrix.” Collins’s approach is to select a virus that already targets the bacteria of interest, such as E. coli or Staphylococcus. Then he introduces into the virus a gene for an enzyme that dissolves the main carbohydrate component of the biofilm matrix protecting the bacteria.

There are viruses specialized to infect every bacterial species. These viruses replicate inside bacterial cells, then burst them open, killing the bacteria, and spread to other bacterial cells. But they do not harm animal cells or bacteria other than the kind to which they are targeted.

Naturally occurring viruses can attack biofilms. But Collins showed that giving a virus a gene for dissolving the matrix increased the virus’s effectiveness by 4.5 orders of magnitude.

Collins’s proof-of-concept virus is tailored to a particular type of E. coli biofilm. “There are many species and strains of bacteria out there,” he says, and a single biofilm might support multiple bacterial species and strains. To a lesser degree, there is also some diversity in the components of the biofilm matrix. However, Collins says that because of the increasing speed and falling price of DNA-sequencing and synthesis technologies, it would not be difficult to develop a virus tailored to each kind of biofilm.

Collins’s viral technique appears to overcome some of the problems with chemical techniques. Blackwell, who is designing small molecules to disrupt the bacterial signaling pathways that maintain biofilms, says that delivery of biofilm-disrupting chemicals such as enzymes has been a major hurdle.

The risks of such viruses are unclear, but there is some concern that they might provoke a dangerous immune response. One reason they might not have been widely studied for their potential to treat infection, says Collins, is that antibiotics have been sufficient so far. But with the emergence of multi-drug resistant bacterial strains in hospitals, “a number of companies are looking to viruses,” he says.

For industrial applications where you’re not putting them in someone’s body, these viruses could have a huge impact”. Finding and farming bacteria could change the way we live.

Here we go again. Another outbreak of gastroenteritis has affected 47 people at a nursing home at South Morang, North of Melbourne.

The illness struck 30 residents and 17 staff at the San Carlo Home for the Aged. Although it is still early, the source of the illness remains unknown.

One of the victims, a 90-year-old man, has died, but the cause of death is not yet known as it could be of natural causes.

San Carlo Home spokesman Christian Peterson says family members were asked to stay away from the home over the weekend.

“The best way people can help is by staying away and letting the staff get on with the job of looking after the residents and helping prevent the spread further,” he said.

“At all times we’ll keep relatives, staff and the appropriate agencies informed, as we have done over the last few days.”

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.

Mycobacterium tuberculosis has thrived in South Asia for over 100 years, but until now no one had studied the diversity of the strains present. To do this, Niyaz Ahmed and his colleagues from the University of Hyderabad, India, analysed 91 samples of tuberculosis taken from all over the country, studying the number and type of short, repetitive DNA sequences within three key genes.

They discovered that the ancestral strain is widespread, suggesting that India is the ancient reservoir for tuberculosis, from which more recent strains evolved and spread to other countries.

This may have enabled the immune systems of people living there to adapt to it, providing some degree of protection. However, that might be about to change, because the Indian population is far less well adapted to a recent strain of tuberculosis known as Beijing strain, found in India only since 2002. This highly infectious strain is threatening to replace the ancestral one, says Ahmed, who presented his results at a conference in Bangkok, Thailand, last month. Coinciding with a surge in HIV cases, this could spell disaster for the 5.7 million Indians infected with the virus.

Source: 10 January 2007 From New Scientist Print Edition issue 2585, page 15

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.

source

According to The Canadian Food Inspection Agency (CFIA), salmonella was detected in Maranatha Brand Organic Raw Sesame Tahini. They have warned the public not to consume any of the products.

The affected product, MaraNatha brand Organic Raw Sesame Tahini, No Salt, a product of USA, is sold in 340 g jars bearing UPC 0 51651 09327 9 and Use By date 07/27/07 (July 27, 2007). This product has been distributed nationally.

So far there have been no reported illnesses associated with the consumption of this product.

Any food contaminated with Salmonella may not look or smell spoiled, however it can still cause illness. Consumption of food contaminated with this bacterium may cause salmonellosis, a foodborne illness. In young children, the elderly and people with weakened immune systems such as Aids patients, salmonellosis may cause serious and sometimes fatal infections.

In healthy people, salmonellosis may cause short-term symptoms such as high fever, severe headache, vomiting, nausea, abdominal pain and bloody diarrhea. Long-term complications may include severe arthritis.

The importers are voluntarily recalling (no choice) the affected product from the marketplace and hopefully the manufacturer involved improves its hygiene. The CFIA is currently monitoring the effectiveness of the recall.

After visiting their website, here’s what they say about the quality of their sesame.

“Our Sesame Tahini items are made with the highest quality sesame seeds. The seeds are mechanically hulled, then ground to a perfectly smooth texture. We produce Sesame Tahini in both Organic and Natural varieties to offer a choice to consumers since organic sesame seeds remain higher in price than conventionally grown ones. We also offer the flavor option of Raw or Roasted to provide a choice for discerning cooks and Tahini-lovers. Sesame Tahini is a key ingredient in many popular Middle Eastern and Mediterranean dishes. It also provides an excellent base for dressings and dips.”

In the future they may need to modify the above statement and add it is tested and cleared for all pathogens including salmonella.

For more information, consumers and industry can call the CFIA at 1-800-442-2342 / TTY 1-800-465-7735 (8:00 a.m. to 8:00 p.m. Eastern time, Monday to Friday).

For information on Salmonella, visit the Food Facts web page at http://www.inspection.gc.ca/english/fssa/concen/causee.shtml

For information on receiving recalls by e-mail, or for other food safety facts, visit www.inspection.gc.ca.

Media enquiries:

Shashi Kulkarni (English)
Canadian Food Inspection Agency
Food Recall and Emergency Response
613- 368-1622 Linda LeBlanc (French)
Canadian Food Inspection Agency
Food Recall and Emergency Response
613- 760-4112

According to the Washington Post, a virulent strain of bacillus tuberculosis which is resistant to most available antibiotics is appearing around the world. This has started to raise fears of a pandemic that could devastate efforts to contain the tuberculosis and prove deadly to people with immune-deficiency diseases such as HIV-AIDS or the immuno-compromised.

The strain known formally as extensively drug-resistant tuberculosis or XDR- tuberculosis has been detected in 37 different countries.
It arises when the bacillus bacterium that causes tuberculosis mutates because antibiotics used to destroy it are carelessly administered at a lower level by poorly trained doctors or patients don’t complete their full course of medication. Therefore, rather than being killed by the drugs, the microbe mutates and builds up resistance.

This strain has a high mortality rate and at least 50 percent of those who contract this strain of tuberculosis will die of it.

In the United States, 13,767 tuberculosis cases were recorded in 2006, the lowest rate of infection since reporting began in 1953. A retrospective analysis by the CDC found 49 cases of the new strain in the country since 1993.

Source

After intensive investigation, the source of a salmonella outbreak at the Broughton Hall nursing home will probably never be known as the microbiological tests on suspect food and water samples were all negative.

Due to the long delay between notifications as well as the major clean-up of the area, all evidence of the source is gone.

According to Victoria’s acting Chief Health Officer, Dr John Carnie, says:

“More than 40 food and water samples were tested, as well as equipment used for preparing food in the kitchen,”

One sample taken from a batch of eggs did test positive for salmonella, Dr Carnie said, but it was not the same strain that caused the gastroenteritis outbreak.

“Also, these eggs were not from the same batch consumed prior to the outbreak,” he said.

Although the faecal samples taken from all 11 residents have tested positive for the salmonella, it was not the same strain as the egg. These did not include samples taken from the five residents whose deaths have been linked to the outbreak.

The risk of water being contaminated with salmonella is extremely rare and as a precaution they have only now being allowed to again drink water from the mains supply.

Sharon Callister, chief executive of Benetas, which runs Broughton Hall, said she was relieved at the test results.

“All of the residents affected by the outbreak are stable, recovering well and no longer showing symptoms,” she said.

“We are currently working with the council on the necessary steps needed to reopen the kitchen at Broughton Hall and, again, the residents are looking forward to that happening.”

A Health Department spokesman said it was still most likely that the salmonella outbreak had originated in food prepared in the home’s kitchen. “Just because we haven’t found anything, the epidemiology still points to something that was present in the kitchen at a point in time,” he said.

The contaminated food which was the only evidence is likely to have been eaten or thrown out, he said.

Earlier this week federal Minister for Ageing Christopher Pyne released the results of an independent audit of Broughton Hall. It found the home had failed 12 out of 44 safety benchmarks, including infection control, continence management and nutrition and hydration. This is very poor management.

Here’s is the offical press release:

Minister for Ageing must ensure consistency of standards
Minister Pyne must explain the inconsistencies in the aged care accreditation process after his statement today showed that Broughton Hall was non-compliant on 12 out of 44 Accreditation Outcomes although the facility passed all 44 out of 44 a year ago. These findings come after an audit by the Aged Care Standards and Accreditation Agency. The last assessment of Broughton Hall was in April 2006. “The Minister for Ageing is responsible for the operation and standards of Australia’s 3000 aged care facilities. It is his responsibility to ensure facilities are complaint with all 44 Accreditation Outcomes.

“The Minister was informed about the incidence at Broughton Hall on Saturday 14 April and it took him till 18 April to do anything about it. The Minister needs to explain why it took him so long to take any action,” Senator McLucas said.

“Why is it that every time there has been an aged care incident reported in the media the Agency will visit and find a facility has failed several Accreditation Outcomes but only a short time previously it would have been given a clean bill of health?

“There is a view in the sector that there is inconsistency in the application of the accreditation standards. The Minister must now respond to that community concern and give an assurance that systems are in place so the public can be assured standards are consistent and reliable in Australia’s aged care facilities.”

Senator McLucas extended her condolences to the families of those who died in the outbreak of gastroenteritis in Broughton Hall Nursing Home, and her best wishes for the recovery of those currently hospitalized.

Contact: Senator Jan McLucas 0407 169 206
Heather Witham 0417 010 734

Salmonella has struck again and this time four elderly people are dead from a salmonella outbreak in a Melbourne (Australia) nursing home. The victims belong to the high risk groups and include three men and a woman, aged in their 70s and 80s.

The Broughton Hall nursing home in Camberwell was home to about 30 residents when the outbreak was first detected on April 5.

During the next seven days, a total of 21 residents caught the gastroenteritis bug associated with salmonella; one woman aged 93 remains in a stable condition in hospital.

Investigations are currently in progress to find the source, however a spokesperson says the outbreak has now been contained following de-contamination of the nursing home’s kitchen. Now it’s finding if some of the supplied food is the implicated source.

Both Victoria’s coroner and Human Services department are investigating the deaths.

Broughton Hall executive director Sharon McGowan told the Nine Network her priority was caring for the residents during what had been a difficult period.

“It’s a very difficult time and obviously our priority is actually caring for the residents and keeping families informed,” Ms McGowan said.

“And we have been spending this afternoon, particularly, keeping the families informed.”