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November 17, 2007

Listeria Food Standards gets Debated at CODEX

The EU and US positions at a Codex meeting to set international standards on food safety foreshadow future legislation that would affect hygiene control measures in manufacturing plants, and the manufacture of powdered formulae, ready-to-eat foods, and pasteurised liquid eggs.

In the six day meeting which ended on the 4 November in New Delhi, India, national representatives to Codex’s food hygiene committee also decided to start work on drafting safety guidelines setting standards to control Campylobacter and Salmonella specie in broiler chicken meat.

At the New Delhi meeting they discussed various positions, including those relating to proposed standards for pasteurized liquid whole eggs, hygienic practice for processing powdered formulae for infants and children, pathogen control measures for Listeria monocytogenes in ready-to-eat foods & guidelines for evaluating manufacturing control measures.

Codex is a multilateral body set up to develop food safety and other standards that would apply to all member countries.

It operates under the aegis of the UN’s Food and Agriculture Organisation and the World Health Organisation.

The standards are recognised as international benchmarks by one of the multilateral agreements of the World Trade Organisation (WTO) and aim to eliminate many of what the UN calls “unjustified technical barriers” to food imports set up by some countries.

The standards also serve to harmonise food safety laws globally, aiding multinational processors in following the law no matter where they trade.

The standards on each particular topic and food type can undergo a huge revision process at various levels of Codex decision making bodies, over a number of years. Member countries must then transcribe the standards into their national laws.

The proposed standard setting what pathogen controls for Listeria monocytogenes ready-to-eat food processors must put in place is based in the main on US risk assessments, according to Codex documents.

Based on the risk assessments, a working group led by Germany concluded that a zero tolerance standard for L. monocytogenes have a proportional reduction in the rates of illness from foods contaminated with the pathogen.

A study commissioned by the food hygiene committee showed that the application of microbiological criteria at a given point of the production chain is only one of the measures that need to be applied, to bring down contamination rates.

The committee proposes to exclude from the criteria foods that are processing in such a way to ensure the killing of L. monocytogenes and for which recontamination is not possible.

The foods must also be processed and handled under systems adhering to good hygienic practice (GHP), a separate international standard.

Such foods include those given a listericidal treatment in the package and those that are produced through aseptic processing and packaging.

The group includes dehydrated products such as powdered milk, dehydrated soup mixes, herbs and spices, fresh, uncut and unprocessed vegetables and fruits, soft drinks, beer and spirits.

At the meeting the EU delegation also proposed that the standard should specifically include ready-to-eat foods for infants and those with medical conditions.

The EU supports a 100 colony forming units per gram (cfu/g) limit on the pathogen for ready-to-eat foods, if the food manufacturer is able to demonstrate the maximum would not be exceeded throughout the shelf-life.

The EU delegation also noted that setting a zero tolerance standard, where a negative reading is set at 25g = 0.04 colony forming units per gram (cfu/g) “might cause misunderstandings”.

The EU also wants clarification on foods not covered by the testing standard, pointing out that previous discussions had also discussed products for which Listeria monocytogenes is “very unlikely” to be detected.

Clarification is also needed about the proposed exclusion of foods for which there is less than ’1 log’ growth during 1.3 times the expected shelf life, the EU stated in its submission. Various definitions of ‘shelf-life’ might confuse the issue.

At the meeting the Codex committee also set its priorities for proposed standards, with those for egg products topping the list.

Other priorities in order are standards for infant and children foods; combining two codes of practice for various nuts into one; setting a single hygienic code for fruits, vegetable and products made from them; quick frozen foods, spices and aromatic plants; low-acid and acidified low-acid canned foods and aseptically processed and packaged low-acid canned foods, natural mineral waters, frog legs, catering, and street-vended foods.

The WTO’s Codex Alimentarius Commission is the body set up to harmonise food safety and other export requirements around the world.

Member countries’ representatives meet regularly to debate a common position or standard on every aspect of such requirements, from the holding temperatures in frozen meat should be kept at, to processing requirements for specific types of cheeses.

Agreements forged at Codex meetings could eventually affect the way processors operate worldwide as they become incorporated into national laws in various countries around the world.

Source

August 26, 2007

Food Poisoning: How to Avoid It, How to Treat It

While America’s food supply is the safest in the world, food poisoning is responsible for approximately 76 million illnesses in the United States each year. In fact, it is estimated that 60% or more of the raw poultry sold today probably has disease-causing bacteria. Anyone eating food contaminated by certain bacteria, parasites, or viruses can get food poisoning. Certain factors such as age and physical condition can make certain people more susceptible to food poisoning than others. Infants, pregnant women, the elderly and people with compromised immune systems are at greatest risk.

For most people in good condition, food poisoning is usually neither long lasting nor life-threatening. However, to less healthy individuals it can become a serious health threat, accounting for approximately 5,000 deaths each year.

The good news is that by taking simple precautionary steps while purchasing, handling, and preparing food you can prevent most cases of food poisoning in the home.

What causes food poisoning? Food poisoning is most commonly caused by bacteria, parasites, or viruses that may be present in the food that you have eaten. You may have heard the names of many of these organisms. They include Escherichia coli (E coli), Campylobacter jejuni, Clostridium botulinum, Shigella, Salmonella, Staphylococcus aureus, Trichinella, and Hepatitis A virus, just to name a few. They can be present in a wide range of food including red meat, poultry, milk and other dairy products, eggs, unpasteurized vegetable juices and ciders, spices, chocolate, seafood, and even water.

These organisms may be present on your food when it is bought or can get into the food, including cooked food, if the food comes into contact with raw meat juices on dirty utensils, cutting boards, or countertops used to prepare contaminated food. That’s why it is important not only to thoroughly cook your food, but to wash your hands, utensils, and countertops, before and after you handle raw foods.

What are the symptoms? Symptoms will vary depending on the type and amount of contaminants eaten. Some people may get ill after ingesting only a small amount of harmful bacteria, while others may remain free of symptoms after eating larger quantities. The most common symptoms of food poisoning include nausea, vomiting, diarrhea, stomach pain (cramps), fever, headache, and fatigue. Symptoms may develop as soon as 30 minutes after eating tainted food, but more commonly do not develop for several days or weeks. Symptoms of viral or parasitic food poisoning may not appear for several weeks, while some toxins in fish may take only a few minutes to cause symptoms.

If you have botulism, you probably will not have a fever and the symptoms may include blurred vision, fatigue, dry mouth and throat.

How food poisoning is diagnosed Food poisoning is often suspected when several people become ill after eating the same meal. To diagnose the cause of the illness, your doctor will need to know the symptoms and what was eaten right before the illness occurred. The doctor may need samples of the food, bowel movements, or vomit. These samples can be tested in a laboratory to determine if the food was contaminated and identify the organism causing the illness.

How is it treated? If the symptoms are severe, the victim should see a doctor or get emergency care. Treatment depends on the severity and cause of the food poisoning. Generally, for mild cases of food poisoning, the doctor will recommend for you to rest, drink fluids to prevent dehydration due to vomiting or diarrhea, and to follow a specific diet. It usually only takes about 1 to 5 days to recover from food poisoning.

If you have botulism, your doctor will prescribe an antitoxin. Other types of food poisoning have no antidote. Antibiotics are usually not helpful in treating food poisoning. Medicine to stop vomiting and stomach cramping may be given.

Prevention is the best approach to avoid food poisoning Most cases of food poisoning can be prevented. Below is a list of a few simple Do’s and Don’ts to help you avoid food-borne illness in the home.

● Do wash your hands, utensils, cutting boards, and countertops between different foods ● Do hrefrigerate or freeze perishables right away (Refrigerator temperature should be 41Ëš F and freezer 0ËšF) ● Do thoroughly cook foods. Cook beef, lamb, and pork to an internal temperature of 160ËšF; whole poultry and thighs to 180ËšF; poultry breasts to 170ËšF, ground chicken or turkey to 165ËšF ● Do hrefrigerate leftover foods as soon as possible; leftovers shouldn’t remain unrefrigerated longer than 2 hours. ● While food shopping, do select frozen foods and perishables such as meat, poultry, and fish last- before checking out ● Do use smooth cutting boards made of hard maple or plastic that are free of cracks and crevices ● Do store raw meats in leak-proof containers or on the bottom of the hrefrigerator to prevent juices from dripping on other foods ● Don’t allow uncooked meats, meat juices, or unwashed fruits and vegetables to come in contact with either cooked or washed foods ● Don’t buy frozen seafood if the packages are open, torn, or crushed on the edges ● Don’t buy food in cans that are bulging or dented, or in jars that are cracked ● Don’t ever buy outdated food. Check the “use by” or “sell by” dates ● Don’t buy unpasteurized milk or dairy products ● Do not buy hrefrigerated or frozen products that are not displayed at the proper temperature ● Do not let small children put foods away unsupervised

More information about this important health subject can be obtained from the following sources: Gateway to Government Food Safety Information www.foodsafety.gov U.S. Food and Drug Administration Center for Food Safety and Applied Nutrition http://vm.cfsan.fda.gov/~dms/wh-food.html Food Safety and Inspection Service United States Department of Agriculture www.fsis.usda.gov/OA/pubs/consumerpubs.htm

Supported as an educational service by Novartis Pharmaceuticals Corporation. This information is not intended for use as medical advice. You should discuss this information with your doctor.

Avaraham Henoch, MD 564 West 160th Street New York, NY 10032 Phone: (212) 740-6400

April 4, 2007

Antibiotic resistance plague

A strain of bacterium could easily develop drug-resistance and become a major health threat, warn scientists.

A study, published on the 21 March 2007 in PLoS ONE, found that the drug-resistance genes in a plague bacterium from a 1995 case of the disease were the same as those in many common bacteria and are able to ‘jump’ from bacteria to bacteria.

The researchers say this illustrates how easily Yersinia pestis, the bacterium causing plague can develop resistance to antibiotics, which are vital in the treatment and prevention of the disease. There is no vaccine available for plague and this represents a significant public health concern.

A new multi-drug-resistant form of Yersinia pestis was found in a 16-year-old boy in Madagascar (1995). The strain had developed resistance against eight different groups of antibiotics including streptomycin and tetracycline.

Researchers discovered that the genes conferring this resistance are also in common food poisoning bacterium such as salmonella, E. coli, klebsiella, shigella and listeria from market samples of beef, pork, chicken and turkey in the United States.

As these genes are able to transmit themselves between bacteria, it raises the possibility of drug resistant Yersinia pestis emerging easily.

Lead author Jacques Ravel, of the US-based Institute for Genomic Research, says, “Our agricultural and medical use and abuse of antibiotics is generating a large reservoir of bacteria carrying resistance genes. These genes can transfer from bacteria to bacteria.”

The key to controlling any outbreak of plague lies in prompt treatment with common antibiotics such as tetracycline and streptomycin, which can reduce death rates from 60 to 15 per cent.

Kamal Krishna Datta, former director of India’s National Institute of Communicable Diseases who oversaw the 1994 plague outbreak in Surat, western India says the discovery “needs to be widely shared and discussed and the disease surveillance mechanism strengthened through a global network.”

In the past five years alone, plague has been reported in Algeria, India, Malawi and Zambia. The last reported case was in the Democratic Republic of Congo in 2006.

June 25, 2006

Yersinia enterocolitica

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).

The Genus Yersinia: Entering the Functional Genomic Era

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