What causes allergy to crustaceans

What Are the Signs & Symptoms of a Shellfish Allergy?

When someone is allergic to shellfish, the body’s immune system, which normally fights infections, overreacts to proteins in the shellfish. Every time the person eats (or, in some cases, handles or breathes in) shellfish, the body thinks these proteins are harmful invaders and releases chemicals love . This can cause symptoms such as:

  1. hives
  2. swelling
  3. vomiting
  4. itchy, watery, or swollen eyes
  5. diarrhea
  6. coughing
  7. throat tightness
  8. wheezing
  9. trouble breathing
  10. belly pain
  11. hoarseness
  12. red spots
  13. a drop in blood pressure, causing lightheadedness or loss of consciousness (passing out)

Allergic reactions to shellfish can differ.

Sometimes the same person can react differently at diverse times. Some reactions can be extremely mild and involve only one system of the body, love hives on the skin. Other reactions can be more severe and involve more than one part of the body.

Shellfish allergy can cause a severe reaction called anaphylaxis, even if a previous reaction was mild. Anaphylaxis might start with some of the same symptoms as a less severe reaction, but can quickly get worse.

The person may own trouble breathing or pass out. More than one part of the body might be involved. If it isn’t treated, anaphylaxis can be life-threatening.

How Is an Allergic Reaction to Shellfish Treated?

If you own a shellfish allergy (or any helpful of serious food allergy), the doctor will desire you to carry an epinephrine auto-injector in case of an emergency.

An epinephrine auto-injector is a prescription medicine that comes in a little, easy-to-carry container. It’s simple to use. Your doctor will show you how.

Hold it nearby, not in a locker or in the nurse’s office.

The doctor can also give you an allergy action plan, which helps you prepare for, recognize, and treat an allergic reaction. Share the plan with anyone else who needs to know, such as relatives, school officials, and coaches. Also consider wearing a medical alert bracelet.

Every second counts in an allergic reaction. If you start having serious allergic symptoms, love swelling of the mouth or throat or trouble breathing, use the epinephrine auto-injector correct away. Also use it correct away if your symptoms involve two diverse parts of the body, love hives with vomiting.

Then call 911 and own someone take you to the emergency room. You need to be under medical supervision because even if the worst seems to own passed, a second wave of serious symptoms can happen.

It’s also a excellent thought to carry an over-the-counter (OTC) antihistamine, as this can assist treat mild allergy symptoms. Use after — not as a replacement for — the epinephrine shot during life-threatening reactions.

Managing shellfish allergies in children

Because shellfish allergy reactions, love other food allergy symptoms, can develop when a kid is not with his or her parents, parents need to make certain that their child’s school, day care or other program has a written emergency action plan with instructions on preventing, recognizing and managing these episodes in class and during activities such as sporting events and field trips.

If your kid has been prescribed an auto-injector, be certain that you and those responsible for supervising your kid understand how to use it.

This sheet was reviewed and updated as of 2/13/2019.

en españolAlergia al marisco

What Is a Shellfish Allergy?

A shellfish allergy is not exactly the same as a seafood allergy. Seafood includes fish (like tuna or cod) and shellfish (like lobster or clams). Even though they both drop into the category of "seafood," fish and shellfish are biologically diverse. So fish will not cause an allergic reaction in someone with a shellfish allergy, unless that person also has a fish allergy.

Shellfish drop into two diverse groups:

  1. crustaceans, love shrimp, crab, or lobster
  2. mollusks, love clams, mussels, oysters, scallops, octopus, or squid

Some people with shellfish allergies are allergic to both groups, but some are allergic only to one.

Most allergic reactions to shellfish happen when someone eats shellfish.

But sometimes a person can react to touching shellfish or breathing in vapors from cooking shellfish.

Shellfish allergy can develop at any age. Even people who own eaten shellfish in the past can develop an allergy. Some people outgrow certain food allergies over time, but those with shellfish allergies generally own the allergy for the relax of their lives.

Managing a severe food reaction with epinephrine

Shellfish is among the most common food allergens. But every food allergies can be dangerous.

Epinephrine is the first-line treatment for anaphylaxis, a severe whole-body allergic reaction that causes symptoms, including tightening of the airway.

Anaphylaxis can happen within seconds or minutes of exposure to the allergen, can worsen quickly, and can be deadly.

Once a food allergy diagnosis is made, your allergist likely will prescribe an epinephrine auto-injector and teach you how to use it. Check the expiration date of your auto-injector, note the expiration date on your calendar and enquire your pharmacy about reminder services for prescription renewals.

Be certain to own two doses available, as the severe reaction may recur.

Epinephrine should be used immediately if you experience severe symptoms such as shortness of breath, repetitive coughing, feeble pulse, generalized hives, tightness in the throat, trouble breathing or swallowing, or a combination of symptoms from diverse body areas such as hives, rashes or swelling on the skin coupled with vomiting, diarrhea or abdominal pain. Repeated doses of epinephrine may be necessary.

If you are uncertain whether a reaction requires epinephrine, use it correct away, because the benefits of epinephrine far outweigh the risk that a dose may not own been necessary.

Common side effects of epinephrine may include temporary anxiety, restlessness, dizziness and shakiness.

Rarely, the medication can lead to an abnormal heart rate or rhythm, a heart attack, a sharp increase in blood pressure and fluid buildup in the lungs, but these adverse effects are generally caused by errors in dosing which is unlikely to happen with use of epinephrine autoinjectors. Some people with certain pre-existing conditions might be at higher risk for adverse effects and should speak to their allergist about epinephrine use.

Your allergist will provide you with a written emergency treatment plan that outlines which medications should be istered and when (note that between 10 and 20 percent of life-threatening severe allergic reactions own no skin symptoms).

Be certain you understand how to properly and promptly use an epinephrine auto-injector.

Once you own used your epinephrine auto-injector, immediately call 911 and tell the dispatcher that you used epinephrine and that more may be needed from the emergency responders.

Other medications, such as antihistamine and corticosteroids, may be prescribed to treat mild symptoms of a food allergy, but it is significant to note that there is no substitute for epinephrine — this is the only medication that can reverse the life-threatening symptoms of anaphylaxis.

Sensitivity

The exaggeration of the normal effects of a substance.

For example, the caffeine in a cup of coffee may cause extreme symptoms, such as palpitations and trembling.

Intolerance

Where a substance causes unpleasant symptoms, such as diarrhoea, but does not involve the immune system.

What causes allergy to crustaceans

People with an intolerance to certain foods can typically eat a little quantity without having any problems.

Sheet final reviewed: 22 November 2018
Next review due: 22 November 2021

To prevent a reaction, it is extremely significant to avoid every shellfish and shellfish products. Always read food labels and enquire questions about ingredients before eating a food that you own not prepared yourself.

Most people who are allergic to one group of shellfish are allergic to other types. Your allergist will generally recommend you avoid every kinds of shellfish. If you are allergic to a specific type of shellfish but desire to eat other shellfish, talk to your doctor about further allergy testing.

Steer clear of seafood restaurants, where there is a high risk of food cross-contact.

You should also avoid touching shellfish and going to fish markets. Being in any area where shellfish are being cooked can put you at risk, as shellfish protein could be in the steam.

Shellfish is one of the eight major allergens that must be listed on packaged foods sold in the U.S., as required by federal law.

Avoid foods that contain shellfish or any of these ingredients:

  1. Lobster (langouste, langoustine, Moreton bay bugs, scampi, tomalley)
  2. Prawns
  3. Crawfish (crawdad, crayfish, ecrevisse)
  4. Krill
  5. Crab
  6. Barnacle
  7. Shrimp (crevette, scampi)

Your doctor may advise you to avoid mollusks* or these ingredients:

  1. Scallops
  2. Squid (calamari)
  3. Periwinkle
  4. Sea urchin
  5. Sea cucumber
  6. Cuttlefish
  7. Mussels
  8. Abalone
  9. Clams (cherrystone, geoduck, littleneck, pismo, quahog)
  10. Octopus
  11. Limpet (lapas, opihi)
  12. Cockle
  13. Oysters
  14. Snails (escargot)
  15. Whelk (Turban shell)

*Note: The federal government does not require mollusks to be fully disclosed on product labels.

Shellfish are sometimes found in the following:

  1. Seafood flavoring (e.g., crab or clam extract)
  2. Fish stock
  3. Glucosamine
  4. Cuttlefish ink
  5. Bouillabaisse
  6. Surimi

Once a shellfish allergy is identified, the best management is to avoid the food.

You need to carefully check ingredient labels of food products. You should study other names for the foods you need to avoid to be certain not to eat them.

You must be extra-careful when you eat out. Waiters (and sometimes the kitchen staff) may not always know every dish’s ingredient list. Vapors may carry little particles of shellfish protein, so being shut to where food is being prepared can potentially cause a dangerous reaction in sensitive individuals.

Fortunately, shellfish is an ingredient that is rarely “hidden” in foods.

Shellfish may be found in fish stock, seafood flavoring (for example, crab extract), sushi and surimi. Crustacean shellfish is one of the eight allergens that drop under the labeling requirements of the Food Allergen Labeling and Consumer Protection Act of 2004. This means that manufacturers of packaged food items sold in the United States and containing crustacean shellfish or a crustacean shellfish-based ingredient must state, in clear language, the presence of crustacean shellfish in the product. (Note: Those regulations apply only to crustacean shellfish, such as shrimp, lobster and crab, and not to mollusks, such as oysters, scallops and clams.)

Anyone with a food allergy must understand how to read ingredient labels and practice avoidance measures.

Your allergist can direct you to helpful resources, such as special cookbooks, patient support groups and registered dietitians, who can assist you plan your meals.

Many people with food allergies wonder if their condition is permanent. There is no clear-cut answer. Over time, allergies to milk, eggs and soy may vanish. Allergies to peanuts, tree nuts, fish and shellfish typically final a lifetime. About one-third of children and adults with a food allergy eventually outgrow the allergy. But rates of naturally outgrowing food allergies will vary depending on the specific food allergen and the person.

Allergy

A reaction produced by the body’s immune system when exposed to a normally harmless substance.

What Else Should I Know?

If allergy testing shows that you own a shellfish allergy, you must not eat shellfish.

You also must not eat any foods that might contain shellfish as ingredients. Anyone who is sensitive to the smell of cooking shellfish should avoid restaurants and other areas where shellfish is being cooked.

For information on foods to avoid, check sites such as the Food Allergy Research and Education network (FARE).

Always read food labels to see if a food contains shellfish. Manufacturers of foods sold in the United States must state whether foods contain any of the top eight most common allergens, including crustacean shellfish.

The label should list "shellfish" in the ingredient list or tell "Contains shellfish" after the list.

Some foods glance OK from the ingredient list, but while being made they can come in contact with fish. This is called cross-contamination. Glance for advisory statements such as "May contain fish," "Processed in a facility that also processes fish," or "Manufactured on equipment also used for fish." Not every companies label for cross-contamination, so if in doubt, call or email the company to be sure.

Manufacturers also do not own to list mollusk shellfish ingredients because mollusk shellfish (clams, mussels, oysters, or scallops) are not considered a major food allergen.

When labels tell a food contains shellfish, they refer to crustacean shellfish. Contact the company to see about cross-contamination risk with mollusks.

Cross-contamination often happens in restaurants.

What causes allergy to crustaceans

In kitchens, shellfish can get into a food product because the staff use the same surfaces, utensils (like knives, cutting boards, or pans), or oil to prepare both shellfish and other foods.

This is particularly common in seafood restaurants, so some people discover it safer to avoid these restaurants. Shellfish is also used in a lot of Asian cooking, so there’s a risk of cross-contamination in Chinese, Vietnamese, Thai, or Japanese restaurants. When eating at restaurants, it may be best to avoid fried foods because numerous places cook chicken, French fries, and shellfish in the same oil.

When eating away from home, make certain you own an epinephrine auto-injector with you and that it hasn’t expired.

Also, tell the people preparing or serving your food about the shellfish allergy. Sometimes, you may desire to bring food with you that you know is safe. Don’t eat at the restaurant if the chef, manager, or owner seems uncomfortable with your request for a safe meal.

Also talk to the staff at school about cross-contamination risks for foods in the cafeteria. It may be best to pack lunches at home so you can control what’s in them.

Other things to hold in mind:

  1. Carry a personalized "chef card," which can be given to the kitchen staff.

    The card details your allergies for food preparers. Food allergy websites provide printable chef card forms in numerous diverse languages.

  2. Stay away from steam tables or stovetops when shellfish is cooked (especially places where food is cooked on a communal grill, love hibachi restaurants).
  3. Tell everyone who handles your food — from relatives to restaurant staff — that you own a shellfish allergy.
  4. Don’t eatcooked foods you didn’t make yourself or anything with unknown ingredients.
  5. Make certain the epinephrine auto-injector is always on hand and that it is not expired.
  6. Shellfish ingredients also might be used in some non-food products, love nutritional supplements, lip gloss, pet foods, and plant fertilizer.

    Talk to your doctor if you own questions about what is safe.

What is a Food Allergy? There Are Diverse Types of Allergic Reactions to Foods


If your kid has symptoms after eating certain foods, he or she may own a food allergy.

A food allergy occurs when the body’s immune system sees a certain food as harmful and reacts by causing symptoms. This is an allergic reaction. Foods that cause allergic reactions are allergens.

IgE Mediated Food Allergies

The IgE mediated food allergies most common in infants and children are eggs, milk, peanuts, tree nuts, soy and wheat.

The allergic reaction can involve the skin, mouth, eyes, lungs, heart, gut and brain. Some of the symptoms can include:

  1. Feeling love something terrible is about to happen
  2. Immunoglobulin E (IgE) mediated. Symptoms result from the body’s immune system making antibodies called Immunoglobulin E (IgE) antibodies. These IgE antibodies react with a certain food.
  3. Shortness of breath, trouble breathing, wheezing
  4. Stomach pain, vomiting, diarrhea
  5. Swelling of the lips, tongue or throat
  6. Skin rash, itching, hives
  7. Non-IgE mediated. Other parts of the body’s immune system react to a certain food.

    This reaction causes symptoms, but does not involve an IgE antibody. Someone can own both IgE mediated and non-IgE mediated food allergies.

Sometimes allergy symptoms are mild. Other times they can be severe. Take every allergic symptoms seriously. Mild and severe symptoms can lead to a serious allergic reaction called anaphylaxis (anna-fih-LACK-sis). This reaction generally involves more than one part of the body and can get worse quick. Anaphylaxis must be treated correct away to provide the best chance for improvement and prevent serious, potentially life-threatening complications.

Treat anaphylaxis with epinephrine.

This medicine is safe and comes in an easy-to-use device called an auto-injector. You can’t rely on antihistamines to treat anaphylaxis. The symptoms of an anaphylactic reaction happen shortly after contact with an allergen. In some individuals, there may be a delay of two to three hours before symptoms first appear.

Cross-Reactivity and Oral Allergy Syndrome

Having an IgE mediated allergy to one food can mean your kid is allergic to similar foods. For example, if your kid is allergic to shrimp, he or she may be allergic to other types of shellfish, such as crab or crayfish.

What causes allergy to crustaceans

Or if your kid is allergic to cow’s milk, he or she may also be allergic to goat’s and sheep’s milk. The reaction between diverse foods is called cross-reactivity. This happens when proteins in one food are similar to the proteins in another food.

Cross-reactivity also can happen between latex and certain foods. For example, a kid who has an allergy to latex may also own an allergy to bananas, avocados, kiwis or chestnuts.

Some people who own allergies to pollens, such as ragweed and grasses, may also be allergic to some foods. Proteins in the pollens are love the proteins in some fruits and vegetables.

So, if your kid is allergic to ragweed, he or she may own an allergic reaction to melons and bananas. That’s because the protein in ragweed looks love the proteins in melons and bananas. This condition is oral allergy syndrome.

Symptoms of an oral allergy syndrome include an itchy mouth, throat or tongue. Symptoms can be more severe and may include hives, shortness of breath and vomiting. Reactions generally happen only when someone eats raw food. In rare cases, reactions can be life-threatening and need epinephrine.

Two Categories of Food Allergies

  • Immunoglobulin E (IgE) mediated.

    Symptoms result from the body’s immune system making antibodies called Immunoglobulin E (IgE) antibodies. These IgE antibodies react with a certain food.

  • Non-IgE mediated. Other parts of the body’s immune system react to a certain food. This reaction causes symptoms, but does not involve an IgE antibody. Someone can own both IgE mediated and non-IgE mediated food allergies.

Non-IgE Mediated Food Allergies

Most symptoms of non-IgE mediated food allergies involve the digestive tract. Symptoms may be vomiting and diarrhea. The symptoms can take longer to develop and may final longer than IgE mediated allergy symptoms.

Sometimes, a reaction to a food allergen occurs up 3 days after eating the food allergen.

When an allergic reaction occurs with this type of allergy, epinephrine is generally not needed. In general, the best way to treat these allergies is to stay away from the food that causes the reaction. Under are examples of conditions related to non-IgE mediated food allergies.

Not every children who react to a certain food own an allergy. They may own food intolerance. Examples are lactose intolerance, gluten intolerance, sulfite sensitivity or dye sensitivity. Staying away from these foods is the best way to avoid a reaction.

Your child’s doctor may propose other steps to prevent a reaction.

What causes allergy to crustaceans

If your kid has any food allergy symptoms, see your child’s doctor or allergist. Only a doctor can properly diagnose whether your kid has an IgE- or non-IgE food allergy. Both can be present in some children.

Eosinophilic Esophagitis (EoE)

Eosinophilic (ee-uh-sin-uh-fil-ik) esophagitis is an inflamed esophagus. The esophagus is a tube from the throat to the stomach. An allergy to a food can cause this condition.

With EoE, swallowing food can be hard and painful. Symptoms in infants and toddlers are irritability, problems with eating and poor weight acquire.

What causes allergy to crustaceans

Older children may own reflux, vomiting, stomach pain, chest pain and a feeling love food is “stuck” in their throat. The symptoms can happen days or even weeks after eating a food allergen.

EoE is treated by special diets that remove the foods that are causing the condition. Medication may also be used to reduce inflammation.

Food Protein-Induced Enterocolitis Syndrome (FPIES)

FPIES is another type of food allergy.

It most often affects young infants. Symptoms generally don’t appear for two or more hours. Symptoms include vomiting, which starts about 2 hours or later after eating the food causing the condition. This condition can also cause diarrhea and failure to acquire weight or height. Once the baby stops eating the food causing the allergy, the symptoms go away. Rarely, severe vomiting and diarrhea can happen which can lead to dehydration and even shock. Shock occurs when the body is not getting enough blood flow.

Emergency treatment for severe symptoms must happen correct away at a hospital. The foods most likely to cause a reaction are dairy, soy, rice, oat, barley, green beans, peas, sweet potatoes, squash and poultry.

Allergic Proctocolitis

Allergic proctocolitis is an allergy to formula or breast milk. This condition inflames the lower part of the intestine. It affects infants in their first year of life and generally ends by age 1 year.

The symptoms include blood-streaked, watery and mucus-filled stools.

Infants may also develop green stools, diarrhea, vomiting, anemia (low blood count) and fussiness. When properly diagnosed, symptoms resolve once the offending food(s) are removed from the diet.

Medical review December 2014.

Non-IgE Mediated Food Allergies

Most symptoms of non-IgE mediated food allergies involve the digestive tract. Symptoms may be vomiting and diarrhea. The symptoms can take longer to develop and may final longer than IgE mediated allergy symptoms.

Sometimes, a reaction to a food allergen occurs up 3 days after eating the food allergen.

When an allergic reaction occurs with this type of allergy, epinephrine is generally not needed. In general, the best way to treat these allergies is to stay away from the food that causes the reaction. Under are examples of conditions related to non-IgE mediated food allergies.

Not every children who react to a certain food own an allergy. They may own food intolerance. Examples are lactose intolerance, gluten intolerance, sulfite sensitivity or dye sensitivity. Staying away from these foods is the best way to avoid a reaction.

Your child’s doctor may propose other steps to prevent a reaction. If your kid has any food allergy symptoms, see your child’s doctor or allergist. Only a doctor can properly diagnose whether your kid has an IgE- or non-IgE food allergy. Both can be present in some children.

Eosinophilic Esophagitis (EoE)

Eosinophilic (ee-uh-sin-uh-fil-ik) esophagitis is an inflamed esophagus.

What causes allergy to crustaceans

The esophagus is a tube from the throat to the stomach. An allergy to a food can cause this condition.

With EoE, swallowing food can be hard and painful. Symptoms in infants and toddlers are irritability, problems with eating and poor weight acquire. Older children may own reflux, vomiting, stomach pain, chest pain and a feeling love food is “stuck” in their throat. The symptoms can happen days or even weeks after eating a food allergen.

EoE is treated by special diets that remove the foods that are causing the condition.

Medication may also be used to reduce inflammation.

Food Protein-Induced Enterocolitis Syndrome (FPIES)

FPIES is another type of food allergy. It most often affects young infants. Symptoms generally don’t appear for two or more hours. Symptoms include vomiting, which starts about 2 hours or later after eating the food causing the condition. This condition can also cause diarrhea and failure to acquire weight or height. Once the baby stops eating the food causing the allergy, the symptoms go away.

Rarely, severe vomiting and diarrhea can happen which can lead to dehydration and even shock. Shock occurs when the body is not getting enough blood flow. Emergency treatment for severe symptoms must happen correct away at a hospital. The foods most likely to cause a reaction are dairy, soy, rice, oat, barley, green beans, peas, sweet potatoes, squash and poultry.

Allergic Proctocolitis

Allergic proctocolitis is an allergy to formula or breast milk. This condition inflames the lower part of the intestine. It affects infants in their first year of life and generally ends by age 1 year.

The symptoms include blood-streaked, watery and mucus-filled stools.

Infants may also develop green stools, diarrhea, vomiting, anemia (low blood count) and fussiness. When properly diagnosed, symptoms resolve once the offending food(s) are removed from the diet.

Medical review December 2014.


Getting assist for allergies

See a GP if you ponder you or your kid might own had an allergic reaction to something.

The symptoms of an allergic reaction can also be caused by other conditions.

A GP can assist determine whether it’s likely you own an allergy.

If they ponder you might own a mild allergy, they can offer advice and treatment to assist manage the condition.

If your allergy is particularly severe or it’s not clear what you’re allergic to, they may refer you to an allergy specialist for testing and advice about treatment.

Find out more about allergy testing


Common allergies

Substances that cause allergic reactions are called allergens.

What causes allergy to crustaceans

The more common allergens include:

  1. latex – used to make some gloves and condoms
  2. mould – these can release little particles into the air that you can breathe in
  3. insect bites and stings
  4. medicines – including ibuprofen, aspirin and certain antibiotics
  5. food – particularly nuts, fruit, shellfish, eggs and cows’ milk
  6. dust mites
  7. animal dander, tiny flakes of skin or hair
  8. grass and tree pollen – an allergy to these is known as hay fever (allergic rhinitis)
  9. household chemicals – including those in detergents and hair dyes

Most of these allergens are generally harmless to people who are not allergic to them.


What causes allergies?

Allergies occur when the body’s immune system reacts to a specific substance as though it’s harmful.

It’s not clear why this happens, but most people affected own a family history of allergies or own closely related conditions, such as asthma or eczema.

The number of people with allergies is increasing every year.

The reasons for this are not understood, but 1 of the main theories is it’s the result of living in a cleaner, germ-free environment, which reduces the number of germs our immune system has to deal with.

It’s thought this may cause it to overreact when it comes into contact with harmless substances.


How to manage an allergy

In many cases, the most effective way of managing an allergy is to avoid the allergen that causes the reaction whenever possible.

For example, if you own a food allergy, you should check a food’s ingredients list for allergens before eating it.

There are also several medicines available to help control symptoms of allergic reactions, including:

  1. lotions and creams, such as moisturising creams (emollients) – these can reduce skin redness and itchiness
  2. decongestants – tablets, capsules, nasal sprays or liquids that can be used as a short-term treatment for a blocked nose
  3. antihistamines – these can be taken when you notice the symptoms of a reaction, or before being exposed to an allergen, to stop a reaction occurring
  4. steroid medicines – sprays, drops, creams, inhalers and tablets that can assist reduce redness and swelling caused by an allergic reaction

For some people with extremely severe allergies, a treatment called immunotherapy may be recommended.

This involves being exposed to the allergen in a controlled way over a number of years so your body gets used to it and does not react to it so severely.


Symptoms of an allergic reaction

Allergic reactions generally happen quickly within a few minutes of exposure to an allergen.

They can cause:

  1. a red, itchy rash
  2. wheezing and coughing
  3. red, itchy, watery eyes
  4. a runny or blocked nose
  5. sneezing
  6. worsening of asthma or eczema symptoms

Most allergic reactions are mild, but occasionally a severe reaction called anaphylaxis or anaphylactic shock can happen.

This is a medical emergency and needs urgent treatment.


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