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6 things a food poisoning expert would never eat

<p>If you want to know how to avoid food poisoning, you better listen to food poisoning expert and lawyer Bill Marler.</p> <p>He’s a products liability and personal injury attorney specialising in food-borne illnesses as well as the managing partner of Marler Clark, dubbed “The Food Safety Law Firm”. With twenty years in the industry, he’s won more than $600 million in compensation claims for his clients since 1998.</p> <p>In an article posted in the <a href="http://www.foodpoisonjournal.com/food-poisoning-information/six-foods-bill-marler-never-eats/#.VrJ3Kvl96uV" target="_blank" rel="noopener"><strong><span><em>Food Poisoning Journal</em></span></strong></a>, Bill has revealed the six foods he refused to eat.</p> <p><strong>Unpasteurised (“raw”) milk and packaged juices</strong></p> <p>Unpasteurised milk, sometimes called “raw” milk, can be contaminated with bacteria, viruses and parasites. Between 1998 and 2011, there were 148 food poisoning outbreaks linked to raw milk and raw milk products in the US—and keep in mind that comparatively few people in the country ever consume these products, so 148 outbreaks is nothing to ignore. As for unpasteurised packaged juices, one of Marler’s earliest cases was the 1996 E. coli outbreak from unpasteurised Odwalla apple juice. As a result, he won’t go near raw milk or juice. “There’s no benefit big enough to take away the risk of drinking products that can be made safe by pasteurisation,” he says.</p> <p><strong>Raw sprouts</strong></p> <p>Uncooked and lightly cooked sprouts have been linked to more than 30 bacterial outbreaks (mostly of salmonella and E. coli) in the US since mid-1990s. As recently as 2014, salmonella from bean sprouts sent 19 people to the hospital. All types of sprouts - including alfalfa, mung bean, clover and radish sprouts - can spread infection, which is caused by bacterial contamination of their seeds. “There have been too many outbreaks to not pay attention to the risk of sprout contamination,” Marler says. “Those are products that I just don’t eat at all.” He did add that he does eat them if they’re cooked.</p> <p><strong>Meat that isn’t well-done</strong></p> <p>Marler orders his burgers well-done. “The reason ground products are more problematic and need to be cooked more thoroughly is that any bacteria that’s on the surface of the meat can be ground inside of it,” Marler says. “If it’s not cooked thoroughly to 160°F throughout, it can cause poisoning by E. coli and salmonella and other bacterial illnesses.” As for steaks, needle tenderising - a common restaurant practice in which the steak is pierced with needles or sliced with knives to break down the muscle fibres and make it more tender - can also transfer bugs from the surface to the interior of the meat. If a restaurant does this (Marler asks), he orders his steak well-done. If the restaurant doesn’t, he’ll opt for medium-well.</p> <p><strong>Prewashed or precut fruits and vegetables</strong></p> <p>“I avoid these like the plague,” Marler says. Why? The more a food is handled and processed, the more likely it is to become tainted. “We’ve gotten so used to the convenience of mass-produced food - bagged salad and boxed salads and precut this and precut that,” Marler says. “Convenience is great but sometimes I think it isn’t worth the risk.” He buys unwashed, uncut produce in small amounts and eats it within three to four days to reduce the risk for listeria, a deadly bug that grows at refrigerator temps.</p> <p><strong>Raw or undercooked eggs</strong></p> <p>You may remember the salmonella epidemic of the 1980s and early ’90s that was linked mainly to eggs. If you swore off raw eggs back then, you might as well stick with it. The most recent salmonella outbreak from eggs, in 2010, caused roughly 2,000 reported cases of illness. “I think the risk of egg contamination is much lower today than it was 20 years ago for salmonella, but I still eat my eggs well-cooked,” Marler says.</p> <p><strong>Raw oysters and other raw shellfish</strong></p> <p>Marler says that raw shellfish - especially oysters - have been causing more foodborne illness lately. He links this to warming waters, which produce more microbial growth. “Oysters are filter feeders, so they pick up everything that’s in the water,” he explains. “If there’s bacteria in the water it’ll get into their system, and if you eat it you could have trouble. I’ve seen a lot more of that over the last five years than I saw in the last 20 years. It’s simply not worth the risk.”</p> <p><em>Images: Shutterstock</em></p>

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Shellfish allergies: Can they be treated?

<p>Seafood platters? Bouillabaisse? Arroz de Marisco? Seafood paella? Oysters Rockefeller? Lobster Thermidor? Dining out with friends, a romantic meal, celebrating Christmas or a holiday on a wind-swept coast with these seafood dishes on your table are enjoyable moments.</p> <p>But have any of you, your friends or family experienced swelling of lips or eyelids, itchiness and rashes developed over your face or body, or even difficulty in breathing just a few minutes after eating shrimp, lobster, crab, clam, mussels, oysters or scallops? If yes, you could well have a shellfish allergy.</p> <p><strong>What is shellfish allergy?</strong></p> <p>Shellfish allergy is a type of hyper-immune response mediated by <a href="https://fr.wikipedia.org/wiki/Immunoglobuline_E">Immunoglobulin E</a> (IgE), an antibody produced by B cells.</p> <p>When someone who is allergic eats some shellfish, the allergens – primary <a href="https://en.wikipedia.org/wiki/Tropomyosin">tropomyosin</a>, a muscle protein – bind with IgE. This allergen-IgE complex then cross-links on mast cells. These cells play a key role in the inflammatory process, by which they contain many granules rich in inflammatory mediators like <a href="https://en.wikipedia.org/wiki/Histamine">histamine</a>. Histamine can increase the permeability of the blood capillaries, exert effects on mucous glands and bronchila tubes, and is a central mediator of allergic reactions like itching.</p> <p><strong>A lifelong condition</strong></p> <p>As designated by the United States <a href="https://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/Allergens/ucm106890.htm">Food Allergen Labelling and Consumer Protection Act</a>, crustacean shellfish are one of the top eight allergens alongside with milk, eggs, peanuts, tree nuts, wheat, soybeans and fish accounting for 90 per cent of food-related allergic reactions.</p> <p>Unlike allergies to egg and cow’s milk for which children often gradually acquire <a href="https://link.springer.com/article/10.1007%2Fs11882-016-0627-4">natural tolerance</a>, shellfish allergies usually <a href="https://link.springer.com/article/10.1007%2Fs11882-016-0627-4">persist throughout life</a>.</p> <p>Shellfish is the leading offending food in the United States, Canada, Portugal, and in the Asia-Pacific regions, including <a href="https://www.ncbi.nlm.nih.gov/pubmed/18808390">Hong Kong and Taiwan</a>. A <a href="https://www.ncbi.nlm.nih.gov/pubmed/24372074">multi-centre survey</a> conducted in Europe, on the other hand, reported 4.8 per cent of adults with IgE sensitisation to shrimp and in some areas like Zurich, the sensitisation rate can be up to 7 per cent.</p> <p><strong>Poor diagnosis</strong></p> <p>Despite such a high impact, diagnosis and treatment of shellfish allergy remains suboptimal. The standard clinical diagnostic involves a thorough review of a patient’s clinical history followed by <a href="https://www.mayoclinic.org/tests-procedures/allergy-tests/about/pac-20392895">skin prick test</a> (SPT) and measurement of shellfish-specific IgE level. A SPT reaction spot that is 3mm or more in diameter and an IgE level of greater than or equal to 0.35 kUA/L which stands for kilo unit of allergen-specific IgE per litre, are commonly defined as a positive diagnosis of a shellfish allergy.</p> <p>However, the rapidly growing number of diagnoses have highlighted concerning the <a href="https://www.ncbi.nlm.nih.gov/pubmed/21651567">shortcomings of these conventional procedures</a>. SPT and IgE measurement with shellfish extract have low specificity of only 50 per cent, meaning that 50 per cent of people with a positive result in these tests may never experience clinical symptoms of shellfish allergy.</p> <div class="embed-responsive embed-responsive-16by9"><iframe class="embed-responsive-item" src="https://www.youtube.com/embed/M_qeE5BsynY"></iframe></div> <div class="embed-responsive embed-responsive-16by9"><span class="caption">Skin prick tests are usually efficient to determine allergies but also present several shortcomings (Imperial College London).</span></div> <p>Although reactions to all sorts of shellfish is common, <a href="https://www.ncbi.nlm.nih.gov/pubmed/18498545">reports</a> have suggested species-specific allergic reactions – for example, you may be able to eat one species of prawn even if you are allergic to another. However, because tests cannot identify cross-reactivity, patients are often suggested to avoid all types of shellfish if they have allergic reactions to one type of shellfish.</p> <p>The oral food challenge, a test that involve giving increasing amounts of a food to a patient to determine if he or she has a food allergy, remains the gold standard. But it is resource-intensive, time-consuming, costly and risky. Subjects’ reluctance due to a fear of <a href="https://www.ncbi.nlm.nih.gov/pubmed/30298065">side effects</a> preclude the implementation of this procedure in clinical settings.</p> <p><strong>Treatment could be improved</strong></p> <p>“Active” treatment options that would desensitize shellfish-allergic patients are unfortunately not yet available. Patients are recommended to avoid shellfish that trigger symptoms, educated to read food labels to avoid accidental consumption, take antihistamines to alleviate mild symptoms, and use epinephrine auto-injector – a hand-held device that delivers epinephrine to relax the airways by intramuscular injection – in case of an anaphylactic reaction. However, none of these first-line measures cures the disease.</p> <p>Food desensitisation and tolerance induction could be achieved by “re-educating” the immune system through giving small doses of the offending food and increasing it over time. However, existing interventions have reservations and limitations: the efficacy in developing tolerance is debatable; the adherence of patients is poor as the treatment is lengthy (2 to 5 years to “complete”); there are risks such as developing allergic side effects; and they’re costly, running between US$800 and $1,000 per year.</p> <p>Our research team therefore focused our effort to address these shortcomings through investigating the value of <a href="https://www.ncbi.nlm.nih.gov/pubmed/26610061">peptide-based oral immunotherapy</a>, by which these peptides are short fragments of tropomyosin with molecular nature of modifying the immune system, and also by constructing hypoallergens of shrimp <a href="https://www.ncbi.nlm.nih.gov/pubmed/25365343">tropomyosin</a> and hypoallergen-based vaccines. Hypoallergens are modified from tropomyosin to be less than normally allergenic.</p> <p><strong>Using a small DNA molecule to counter the allergy</strong></p> <p>With the lower IgE reactivity, hypoallergens are of lower risk in triggering allergic reactions. We also adopted the concept of <a href="https://www.livescience.com/37247-dna.html">DNA</a> vaccination – the injection the DNA sequence of the hypoallergen in a small circular piece of bacterial DNA.</p> <p>When taken up by body cells, this piece of circular DNA is used by the cells’ machinery to produce the hypoallergen protein. Because these proteins are regarded as foreign, the immune system is alerted to trigger immune response. The continual production of the hypoallergen protein by the vaccine and body cells therefore “educates” the immune system as in the conventional immunotherapy but achieved with fewer shots.</p> <p>This combinatorial approach offers the advantages of improved vaccine stability, relative ease of large-scale manufacture, reduced shots and treatment duration, and thus a lower cost of immunotherapy.</p> <div class="embed-responsive embed-responsive-16by9"><iframe class="embed-responsive-item" src="https://www.youtube.com/embed/8h4FVAJ0Ifs"></iframe></div> <div class="embed-responsive embed-responsive-16by9"><span class="caption">Dr. Wai explaining her hypoallergene-DNA vaccine project.</span></div> <p>From our <a href="https://patents.google.com/patent/US20170107265A1/en">animal experiments</a> three shots of this hypoallergen-DNA vaccine resulted in the decrease of IgE level by 70 per cent, accompanied by the increase in the number and activity of immune cells with regulatory functions. This suggests that this vaccine may be a valuable treatment for inducing immune tolerance against shellfish allergy achievable with much fewer injections and within shorter time period.</p> <p>However, the only FDA-approved plasmid, pVAX1, has limited immunogenicity in human, meaning that DNA vaccines constructed using pVAX1 has limited capacity in provoking immune responses in the body of a human.</p> <p>Engineering next-generation vaccines with optimised plasmids and studying their effects and mechanism would be our next steps, and we hope to provide a promising option in the future. Until then, be cautious with that lobster.</p> <p><em>Written by <span>Christine Wai, Post-doctoral researcher, Axa research fund fellow, Chinese University of Hong Kong</span>. Republished with permission of </em><a href="https://theconversation.com/shellfish-allergies-can-they-be-treated-112143"><em>The Conversation</em></a><em>. </em></p>

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