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Another food recall and this time it is product manufactured by a South Australian company with the recall initiated by the NSW food Authority.

This came about after The New South Wales Food Authority issued an alert after several batches of chicken cacciatore, made by the San Marino Smallgoods company, were positive for salmonella.

San Marino is voluntarily recalling the products which includes Cacciatore Hot and Mild, Veneto Hot and Mild and Sopressa Mild with use-by dates of August this year.

So far, the NSW Food Authority says it has no evidence that anyone has fallen sick from eating the affected batches.

Food Standards Australia New Zealand has raised another food recall due to the food being contaminated with Listeria monocytogenes. The implicated food is Prosciutto Parma from Serrano. It includes vacuum packed sliced meat and whole legs with the following Use by Date or Lot Code: Prosciutto Parma lot 11-07/5a, Serrano Ham Leg/Slices – 0705070001

Here’s what they say:

“Italian Foods is conducting a recall of the above product in response to testing which indicates the presence of Listeria monocytogenes.

For further information please call Italian Foods 187 John St Lidcombe NSW Phone: (02) 9807 3082″

According to the NSW Food Authority and the Sydney South West Area Health Service (SSWAHS) Public Health Unit, there is an outbreak of gastroenteritis involving 98 people, many of whom ate food products from a Homebush hot bread shop over the weekend.

So far eighteen people have been hospitalized, and public health officers are currently interviewing all cases.

In the majority of cases interviewed so far, many reported having eaten either pork rolls or chicken rolls from the a Vietnamese bakery called the French Golden Hot Bread shop in Homebush West, opposite the Flemington train station. So far, thirteen cases have been confirmed as having salmonella infection. Incidentally, food poisoning involving Vietnamese Pork roll has occurred a few times in the past from other similar bakeries around the country.

SSWAHS Public Health Unit warns anyone who may have eaten these food products from the bread shop between Friday 23 March and Tuesday 27 March to be vigilant for the symptoms of salmonella infection and seek medical care.

Common symptoms of salmonella infection include diarrhea, abdominal pain, fever, nausea and vomiting. Symptoms usually last four to seven days.

The NSW Food Authority has advised that it sent inspectors into the bread shop to examine food safety practices and to sample foods for laboratory testing. It has placed a prohibition order on the bread shop restricting it from producing or selling the implicated foods. This basically shuts down the shop.

Dr Leena Gupta, SSWAHS Director of Public Health, recommends that anyone who contracts gastroenteritis should keep up their fluid intake, stay home and not return to work or school until 48 hours after symptoms have stopped.

People suffering symptoms should also not prepare food for others until at least 48 hours after they have completely recovered from the illness.

The U.S. Department of Agriculture has established standards for the composition and shelf stability of various ready-to-eat meat products. These standards may include product pH, moisture:protein ratio, and water activity (aw) values. It is unclear how closely these standards are based on the potential for pathogen growth or toxin production. Because the vacuum packaging used on most ready-to-eat meat products inhibits mold, Staphylococcus aureus is the pathogen most likely to grow on products with reduced aw and increased percentage of water-phase salt. In this study, 34 samples of various ready-to-eat meat products were inoculated with a three-strain mixture of S. aureus, vacuum packaged, and stored at 21 degrees C for 4 weeks. S. aureus numbers decreased by 1.1 to 5.6 log CFU on fermented products (pH < or = 5.1) with a wide range of salt concentrations and moisture content. Similarly, S. aureus numbers decreased by 3.2 to 4.5 log CFU on dried non-acidified jerky (aw < or = 0.82; moisture:protein ratio of < or =0.8). Products that were not fermented or dried clearly supported S. aureus growth and cannot be considered shelf stable. The product pH and moisture:protein ratio were the two compositional factors most highly correlated (R2 = 0.84) with S. aureus survival and growth for the types of products tested, but pH and aw or pH and percentage of water-phase salt also may provide useful predictive guidance (R2 = 0.81 and 0.77, respectively).

Journal of Food Protection 2005 Sep;68(9):1911-5
Ingham HC et al
Department of Food Science, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA. scingham@wisc.edu

This biofilm-producing terrorist is the bane of all industrial microbiologists. Industry can be humming along quite happily and then up pops Listeria and its panic stations. The micro response team rushes to the site armed with gauzes, swabs, sampling and HACCP (Hazard Analysis and Control of Critical Points) plans to do combat.

As we all know the genus Listeria is a gram positive rod, psychrotrophic, and displays a peculiar tumbling motility caused by a low number of peritrichous flagella which beat in a clockwise motion due to a defective CheY gene (Dons et al, 2004). This organism is ubiquitous and is found primarily in soil (Sutherland et al, 2003). The only species that is truly a human opportunistic infector is Listeria monocytogenes, public enemy number one. Its sibling Listeria ivanovii is attempting to cause confusion in the ranks of those over-worked industrial microbiologists. L. ivanovii has shown similar pathogenicity as seen by L. monocytogenes, in mice and other animals, but is rarely seen in humans (FDA/CFSAM, 2003). Are these two species protected or masked by Listeria innocula the harmless one? With the perceived threat of Listeriosis, the government bodies are debating the move towards zero tolerance for the genus. The federal government food body FSANZ standard only states that L. monocytogenes absence is required in ready-to-eat products and the FAO/WHO risk assessment concluded that levels of L. monocytogenes <100 cells per gram has the same risk as zero cells per gram (FAO/WHO, 2001). To complicate matters, Dussarget (2004) stated that of the 13 known serovars of L. monocytogenes, only 1/2a, 1/2b and 4b are responsible for 98% of reported human Listeriosis cases. The serovar 4b is associated with the majority of food borne outbreaks and sporadic cases. This single genus has been responsible for more product recalls and media hype than any other micro-organism. We all have heard of Conroy’s and the two deaths from ham in Adelaide in the last few months. Industries that produce ready-to-eat products all have great concern for this ubiquitous terrorist.

Industry has spent millions on the combat, control and the eradication of this organism. As with all terrorist organizations, the sleeper cells are very hard to find and the fact that Listeria produce a fatty acid biofilm on solid surfaces makes it very difficult to treat with standard chloride based surface sanitizers. This biofilm aids the survival of Listeria due to its lipid composition which is hydrophobic and thus prevents the entrance of water-based sanitizers; it also acts as a food reserve and selects for the survival of other symbiotic organisms that aid in the survival and proliferation of Listeria (Sutherland et al, 2003) (Somers & Wong, 2004). The destruction of one biofilm may lead to the establishment of others from that original source and to product contamination. Biofilms are living entities and thus, when critical mass is achieved, cells detach and contaminate the product. This is known to the industrial microbiologist as ‘spitting’. There is reported resistance developing in the standard chemicals used in the eradication of biofilms (Chavant, 2004). The only effective way to clean down contaminated areas is by high-pressure (area needs to be sealed) acid washes as well as physical scrubbing followed by contact sanitization (quats, chlorine, acid and peroxide sanitizer) – the chemical equivalent of hunting down terrorist cells with thermonuclear warheads. Listeria has also displayed an ability to survive and thrive in some of the most extreme environments found in industry such as saturated brine. Listeria has been associated with many of our most loved and highly consumed foods. These include: ice cream, soft cheeses, smoked salmon, pate, fermented meats, cooked further processed chicken meats and fresh leaf produce (Sutherland et al, 2003). This cowardly bacterium attack the elderly, infirmed and the defenseless fetus with relatively low infective doses, 2 to 3 log less than is required to infect healthy adults (CFSAN, 2003). To complicate matters further, this organism presents to the treating clinician as flu -like systems and initial diagnosis may be difficult.

The total number of victims recorded in Australia is 3 cases in 1,000,000 and is steadily decreasing as the industrial microbiologist is slowly eradicating all known niches. The consumers demand for ‘fresh’ products with minimal preservatives and additives results in additional pressures on the industrial microbiologist to discover strategies to meet the consumer demand without endangering the public. This has resulted in the steady development of non-thermal treatments such as microwave and radio frequency, ohmic and inductive heating, high pressure processing, pulsed electrical field and pulsed light, just to name a few that are in development or have been used in commercial food manufacturing (FDA/CFSAN, 2000). These intervention strategies amplify nature’s only controls in controlling these terrorists. For example, high pressure processing uses water pressures to burst the cell. There is a plethora of methods available for the industrial microbiologist to screen and identify this organism. The selection of methods is primarily based on quality and turnaround time. The longer a company’s product takes to reach the market the more it costs the company. Therefore, there is always pressure to find faster methods to screen out negatives. Some of the most common rapid methods are based either on ELISA type tests (BioMerieux VIDAS, TECRA Unique) or PCR (Oxoid’s BAX and Roche’s real-time PCR protocol). These methods are all automated and have the required regulatory approvals. The covert battle between the industrial microbiologist and Listeria is ongoing with no definite exit time. As long as the consumer enjoys the convenience of ready to eat food, Listeria will be waiting to strike; however, the industrial microbiologist will be there to contain, prevent and eliminate any danger to the public.

Did you know that infections with thermophilic Campylobacter are now generally considered to be the main cause of bacterial enteritis in many developed countries. The infections mainly result from the consumption of contaminated and unheated or only weakly heated food such as poultry.

Human pathogenic campylobacter such as campylobacter jejuni and campylobacter coli are highly infectious and therefore rapid microbiological diagnostics in foods is especially important. Nevertheless, the detection of these species is time-consuming and requires trained personnel.

To simplify the detection of these bacteria MERCK KGaA has developed Singlepath Campylobacter, an immunochromatographic rapid test, which, in a single working process within 20 minutes after 48 h of incubation of the food sample in Bolton broth, specifically detects these bacteria.

A study was conducted for the targeted detection of Campylobacter specie. in natural and in “spiked” food samples were evaluated.

The overall results to date show that the rapid test Singlepath Campylobacter is suitable for the routine examination of food samples for Campylobacter. Die Specificity and sensitivity of the rapid test (in comparison with biochemical culture methods) were measured at 98% and 100%. Singlepath Campylobacter can therefore be considered to be very safe

In comparison with another alternative method, the VIDAS Campylobacter. Singlepath has the advantages of a much shorter detection time, simpler handling and a more attractive price.

This means for routine examinations a clear decrease in operating costs. Occasional false-negative or false-positive results can never be completely excluded with biological material and do not reduce the applicability of the tested method.

Campylobacter is one of those bacteria that causes gastroenteritis, but may also cause systemic illness. It is classified as a pathogen, however it is not seen in the same light as listeria, Salmonella or E.coli. Even the regulators around the world are having doubt if this organism should be regulated.

Who knows, however campylobacter will always be less popular and remain in the shadows of the salmonella, listeria and E.coli.

Symptoms of campylobacter infection include diarrhea with loose bowel movements that maybe bloody, fever and stomach cramps. The most vulnerable to severe infections are the very young, the elderly and malnourished people.

The most frequent cause of the infection is by eating contaminated foods with raw or under cooked poultry being the main culprit. Other sources include household pets, especially puppies and kittens, domestic stock, and contaminated water.

The incubation period for developing the symptoms can vary between 1 – 10 days with this being dependant upon the levels of campylobacter being ingested and the health of the individual. The infected person is infectious for as long as the Campylobacter bacteria are in their faeces, which may be for an average of 2-3 weeks after symptoms are gone. The risk of infecting others decreases when diarrhea is no longer present.

So how do you control this pathogen? Easily, just follow some good personal hygiene.

* Wash hands after handling raw meat, and keep food preparation areas clean
* If possible wear disposable gloves when preparing raw meats.
* Wash hands after gardening, or touching animals and where possible use antiseptic handwash
* Meat, particularly poultry, should be thoroughly cooked
* Do not store uncooked poultry near foods which will be eaten raw, such as salad items
* If pets are sick with diarrhoeal illness, have them treated.

Campylobacter: Molecular And Cellular Biology No Synopsis Available

Yersinia enterocolitica is a gram -ve bacterium that belongs to a family of rod-shaped bacteria. Other species of bacteria in this family include Yersinia pseudotuberculosis, which causes an illness similar to Yersinia enterocolitica and Yersinia pestis, which causes plague.

Yersinia enterocolitica can cause illness in humans, however only a few strains are implicated. These strains are usually found in animals with the majority in pigs. Other strains are also found in many other animals with lower frequency and they include rodents, rabbits, sheep, cattle, horses, dogs, and cats. In pigs, the bacteria are most likely to be found on the tonsils.

Yersinia enterocolitica is commonly present in foods but with the exception of pork, most isolates do not cause disease. Similarly to Listeria this organism is psychrotrophic meaning it can grow at refrigeration temperatures. Although rare, contamination in pasteurized milk has been documented and I’m surprised that it has not been included as an organism of interest in dairy companies around the world. The organism is sensitive to heat (5%) and acidity (pH 4.6), and will normally be inactivated by environmental conditions that will kill coliforms.

The illness caused by Yersinia entercolitica is called Yersiniosis and is common in children. Symptoms are similar to salmonella infection and include fever, abdominal pain, and diarrhea, which is often bloody. The symptoms appear 3 to 7 days after ingestion of the implicated food or exposure and may last up to 3 – 4 weeks.

In older children and adults, abdominal pain may occur predominantly on the right hand side and may be confused with appendicitis. In rare occurrences and in small proportion of cases, complications such as skin rash, joint pains or bacteria infection of the bloodstream can occur (sepecemia).

Campylobacter should not be present in ready-to-eat foods as consumption of food containing this pathogen may result in food borne illness.

The detection of Campylobacter indicates poor food handling controls, particularly cross contamination (especially where raw poultry is handled) or inadequate cooking (e.g. raw or undercooked meat and poultry). The use of raw milk or of contaminated water may be alternative sources of Campylobacter that should be considered.

Campylobacter Progress in Research No Synopsis Available

Ready-to-eat foods should be free of Salmonella as consumption of food containing this pathogen may result in food borne illness. The presence of this organism indicates poor food preparation and handling practices such as inadequate cooking or cross contamination.

Consideration may also be given to investigating the health status of food handlers on the premises who may have been suffering from salmonellosis or asymptomatic carriers of the organism.

Salmonella Parasites are animals, insects, viruses, and microscopic beings that latch onto, trap, trick, and live off of other living things. This series provides a colorful overview of what these yucky creatures are, how they work, what and why they do what they do. Salmonella bacteria lurk in raw eggs, chicken, and other common foods. If allowed to enter the human body, the bacteria multiply quickly and cause a variety of unpleasant diseases, some of which can result in death. In this book the life cycle and effects of this parasite are examined. Containment techniques are also discussed. Accelerated Reader: Reading Level 5.8, 0.5 Points.