Signs of fish poisoning, main causes

Fish is a popular product that is on our table both on weekdays and holidays. The speed of preparation, the simplicity of culinary processing of most types of fish, the relative cheapness (with the exception of delicacy types), ease of digestion and great health benefits make fish a very attractive raw material for various dishes. Many types of fish allow everyone to find a fish to their taste and budget. Alas, we increasingly pay attention to the price of fish, and less and less to its quality. But a stale product can cause severe food poisoning from fish, which can even interrupt a person's life.

Benefits and dangers of fish

It must be said that not everyone likes fish, but the many ways to cook it and the variety of tastes of ready-made dishes help everyone find the one that will suit their taste. Since childhood, we have been told that fish is very healthy, because it contains a large amount of protein and essential fatty acids, phosphorus and iodine, which are so necessary for our body. And this is not the whole list of useful substances.

But what is the optimal iodine content in sea fish worth? After all, this element of the periodic table is not often found in food products, and its deficiency has a negative effect on the thyroid gland. Iodine normalizes cholesterol metabolism and does not allow harmful cholesterol to settle on the walls of blood vessels, disrupting blood flow. Thus, eating fish can be considered a preventive measure against goiter and vascular atherosclerosis.

Fish is also valued for its high content of animal protein, which is necessary for building our cells. And here it doesn’t matter where the fish was caught: in sea waters or in a pond. Yes, meat and eggs are also rich in animal protein. But meat contains more purines than fish, which, when deposited in bone tissue, can provoke the development of gout, and eggs have always been considered a rich source of cholesterol, so eating them in large quantities is not recommended.

But fish is considered a healthy dietary product, because it contains few calories and is easy to digest. It is recommended for both adults and children, for whom fish oil and meat are products that promote normal growth and development. Fish is even included in many therapeutic diets, fortunately, this allows a variety of cooking methods. Boiled and baked fish in foil are considered healthy dietary dishes.

But when talking about the benefits of fish, we must not forget that this is a special product due to the fact that it does not require long-term heat treatment. Moreover, the preparation of dried, salted and dried fish, as well as the Japanese delicacy called "sushi", which is increasingly popular in our country, does not involve exposure to high temperatures at all. In fact, this is raw fish, cooked with the addition of salt, and it can in any case be dangerous for the body, given the conditions in which it lives.

Fish living in freshwater reservoirs quite often become a breeding ground for internal parasites, it is not for nothing that even animals are not recommended to eat fresh river fish due to the risk of helminthiasis. The place where the fish was caught also plays a big role. It is good if it is a clean river or pond far from industrial areas. After all, the meat of fish caught in a reservoir polluted by industrial waste or in an ecologically unfavorable area contains many substances harmful to the body, including heavy metal salts. And it is good if at the time of its catch the fish was alive, and not floating belly up, having died from poisoning with toxins, because these toxins plus decomposition products will subsequently enter the human body, causing severe food intoxication.

The probability of poisoning with waste from sea fish factories is small, unless an oil tanker is in trouble at sea or some other emergency occurs. And helminthiasis does not threaten fish living in salt water, because salt has a detrimental effect on both bacteria and small parasites. But you should not relax here, because fish are capable of accumulating toxic substances from the outside (for example, toxins from some algae). And the mackerel fish varieties beloved by many contain the allergen histidine, which during spawning is converted into saurin - a substance that not only causes severe allergic reactions, but also provokes disruptions in the gastrointestinal tract and cardiovascular system. Therefore, poisoning with sea fish is not such a rare occurrence.

Eating seafood delicacies from rare fish is no less dangerous. The tissues of tropical fish species living near reefs (moray eels, barracudas, groupers and some others) contain a rather poisonous substance – ciguatoxin, which causes severe poisoning in humans and is not destroyed by short-term heat treatment, much less in its absence. The situation is even worse with exotic fish species (the famous fugu fish, raspberries, osman, etc.), whose bodies and entrails contain an even more powerful toxic substance – tetrodotoxin, which cannot be deactivated even by proper heat treatment. Even a small dose of tetrodotoxin can be fatal.

Causes fish poisoning

As we have already understood, the consumption of certain types of fish (reef, exotic, mackerel) is fraught with intoxication of the body and the development of severe allergic reactions. But we also know that toxic substances can be contained in other types of fish living in salt and fresh water bodies, if the fish lived in inappropriate conditions. And this causes great concern, because when buying such a useful product for humans at the market or in the supermarket, the buyer has no idea about the living conditions of the fish, so he cannot immediately determine the cause of poisoning, not realizing that even freshly caught fish can be poisoned.

But for now we have talked about the characteristics of some fish and their habitat conditions, noting several dangerous points here:

• the content of deadly poison in certain exotic varieties of fish,
• accumulation of toxic substances in the tissues of fish living in tropical regions,
• dangerous allergen in mackerel,
• living in ecologically unfavorable regions,
• infestation of fish with parasites in freshwater bodies,
• discharges of industrial waste into water bodies.

Now it's time to touch on the equally important issue of fish storage, because this product is not only very tasty and healthy, but also perishable. At the same time, fish spoilage begins even before an unpleasant smell appears, and pathological processes in it can be recognized only by individual moments: dull eyes, pale gills, ribs sticking out of the belly, etc.

As for sanitary standards, it is not so much the duration of storage of fresh fish that is important, but its conditions. On hot days, fish stored without cold and water can go bad within a few hours. Therefore, inexperienced fishermen often bring home spoiled product from fishing.

While the fish is splashing in the water, there may be nothing harmful in it except helminths and silt, especially if it swam in a clean body of water. But as soon as it dies, the tissues begin to decompose with the participation of opportunistic microorganisms (for example, the ubiquitous staphylococci ), accompanied by the accumulation of significant doses of toxic substances, some of which are the products of the vital activity of microorganisms, and the other is the result of necrotic processes.

The process of fish and meat decomposition can only be stopped by cold, and the lower the storage temperature of the product, the longer it can be stored without fear of fish poisoning. This point is known to those who catch fish, and those who transport it to the place of storage or sale, and the traders themselves. But if in industrial conditions storing fish does not present any particular difficulties, then in the process of its delivery and storage directly at retail outlets, various shortcomings are possible. Fish is often stored not frozen, but chilled (on ice), which reduces its shelf life.

There are cases when fish spoilage occurs already on the fishing vessel, but cunning entrepreneurs freeze such fish and send it to retail outlets. Alas, deep freezing can destroy most bacteria, but not toxic substances. Toxins in fish will not disappear even after heat treatment.

Even if the fish was frozen fresh, it is not a fact that it will end up on our table like that. If it was defrosted during transportation or storage, re-freezing will not be able to correct the situation, because the process of decomposition in the fish begins in a short time.

Bacterial contamination during the consumption of sea and river fish is a more common situation than poisoning with toxins from delicacy fish. Firstly, bacteria are present everywhere, even in the fish's body, but while the fish is alive and healthy, they do not manifest themselves in any way, which is typical, for example, for staphylococci. In dead fish, opportunistic microorganisms become active and, when they enter the human body, can cause food poisoning. Moreover, some types of staphylococcus will not wait for the human immune system to weaken to begin to multiply, but will provoke it themselves.

Incorrect storage conditions of fish near chicken or eggs can cause it to become contaminated with salmonella, which causes a serious disease in humans called salmonellosis. The same situation can be observed if a person carrying salmonella cuts fish with bare hands, after which it ends up on the shelves of retail outlets.

It's scary to think what a person who salts, dries or uses fish with bacteria and toxins to prepare such a Japanese delicacy as sushi condemns himself or other people to. If you don't know, real sushi uses raw fish, without subjecting it to heat treatment.

But poisoning can be obtained not only after eating raw, dried, salted or dried fish (the first two types are considered the most dangerous), but also from dishes prepared using high temperatures. For example, not all bacteria die during the first 10-20 minutes required to cook fish, not to mention the toxins that remain even after long cooking.

Failure to cook fish contaminated with bacteria at sufficient temperature (and some types of fish simply disintegrate into small pieces when exposed to high temperatures for a long time, which looks extremely unattractive on the table) leads to intestinal infections when bacteria change their place of residence.

But again, it is important not only to cook the fish correctly to reduce the risk of possible poisoning, but also to eat it on time. After all, even fish exposed to high temperatures has a limited shelf life, after which decomposition processes begin to occur in it again. Cooked fish that was not eaten immediately after cooking should be stored only in the refrigerator at low temperatures.

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Pathogenesis

In the pathogenesis of fish poisoning, an important role is given to the penetration of poisons and pathogenic microorganisms into the human body when eating liver, caviar, milt and even meat. It is believed that the greatest amount of toxic substances accumulates in the so-called fish by-products, which provokes poisoning with milt, liver or caviar of fish. But some of the toxic substances are also contained in fish meat, so eating only meat (and especially in large quantities) does not at all exclude intoxication and intestinal infections.

When entering the body, various pathogenic factors act differently. Bacteria provoke inflammatory and putrefactive processes in the intestines, and poisons and toxins affect not only the gastrointestinal tract, but also other organs (in particular the central nervous system), consistently affecting them one after another. Parasites deprive the body of the nutrients it needs, and can also penetrate into various organs, disrupting their functioning.

Be that as it may, the penetration of foreign aggressive factors into the body has a negative impact on human health. This is especially noticeable on holidays, because many cannot imagine a feast without fried, salted or smoked fish, fish pies, casseroles and salads. Of course, unscrupulous entrepreneurs know this, for whom pre-holiday days are a great opportunity to get rid of products that are not the first freshness. It is only necessary to give it a marketable appearance, use it as minced meat in cooking and gastronomy, make preserves and canned goods, the freshness of the raw materials in which can only be guessed at, and the issue of expiration is resolved.

According to statistics, the risk of fish poisoning is especially high in the summer, when the shelf life of fish products is reduced due to high ambient temperatures, which means that even frozen fish does not stay frozen for long. High ambient temperatures can cause the product to spoil before it even reaches the counter.

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Symptoms fish poisoning

Since acute fish poisoning can be caused by two main factors: bacteria and poisons, it is customary to distinguish two types (or rather forms) of poisoning. If the cause of the disease is a bacterial factor, it is classified as an intestinal infection (cholera-like form) with its characteristic symptoms. Poisoning with stale fish, regardless of whether the meat was raw, salted or thermally processed, always occurs with the appearance of the following symptoms:

• Spasmodic pain in the abdomen and discomfort in the intestines (rumbling, gas, etc.),
• High fever and chills,
• Constant nausea and vomiting,
• Severe diarrhea, frequent urge to defecate with loose stools,
• Deterioration of general condition, weakness.

The first signs of poisoning can be considered abdominal cramps and nausea. Almost immediately they are joined by vomiting and loose stools, which lead to dehydration. Temperature is already a sign of severe intoxication of the body. And already against this background, the person's condition significantly worsens.

If nothing is done, a person begins to feel constant thirst, his sweating decreases (although at the very beginning it may be increased), dry mouth appears. All these are signs of dehydration of the body, which can have sad consequences. After all, along with water, the body also loses electrolytes necessary for it to carry out vital functions.

Poisoning by poisonous fish species containing potent toxins is referred to as a paralytic form. They manifest themselves as:

• Stomach cramps and intestinal colic,
• Painful nausea and incessant vomiting,
• Severe diarrhea,
• A strong desire to drink,
• Reduction of temperature to critical levels,
• Convulsive syndrome and muscle spasms,
• Panic attacks.

A metallic taste in the mouth, photophobia, decreased heart rate, muscle weakness, and difficulty breathing may also occur.

Neurological symptoms develop gradually and depend on the stage of poisoning. At the initial stage, signs of gastrointestinal disorders prevail. A little later, signs of dehydration appear, intoxication increases, which leads to damage to the central nervous system.

Fugu fish poisoning is a separate conversation, because the toxin it contains is thousands of times stronger than other poisons known to the world. In order to kill a person, only 1 milligram of poison is enough, and one fish contains forty times more.

The delicate taste of the fish, which experts compare to silk, is not all. When eating fugu, a person experiences a strange feeling, on the verge of paralysis (death) and some kind of euphoria, which gives the meal a certain zest that acts like a drug. A person wants to experience this unusual feeling again.

But what threatens him? If the fish was not cooked properly, then in the next quarter of an hour you can expect the appearance of deadly symptoms:

• Severe dizziness with impaired coordination of movements,
• Loss of sensitivity of the tongue and oral cavity, tingling sensation in the lip area,
• Increased salivation,
• Difficulty swallowing,
• Paralysis of the limbs,
• Disruption of the cardiovascular and respiratory systems.

Without assistance (and it should be provided by a specialist), a person dies in a short time from heart failure or respiratory failure. All this is due to the paralytic effect of the poison on the central nervous system, which controls the work of all human organs and systems.

Poisoning with fish of the mackerel family (mackerel, tuna, bonito, horse mackerel, mackerel, etc.) is not considered food poisoning or poisoning. It is rather a special type of severe allergic reaction that occurs with disruption of the digestive system.

Food allergies, the cause of which is believed to be saurin, are characterized by:

• Hyperemia of the skin, i.e. its redness,
• Skin itching, sometimes skin rashes,
• Dyspeptic symptoms, nausea,
• Edema syndrome.

These symptoms may be accompanied by problems with the cardiovascular and respiratory systems, which usually do not lead to death.

How long does it take for fish poisoning to show up?

It depends on the cause of the poisoning. If the cause of the poisoning is a bacterial factor, it takes a certain amount of time for the infection to become "massive" and the amount of toxins produced by the bacteria to cause intoxication of the body. It can take from 30 minutes to 1 hour before the first symptoms of poisoning appear.

If poisoning occurs as a result of eating poisonous fish, symptoms appear within half an hour. The stronger the toxin and the larger the portion, the faster a person will learn about the poisoning. Fugu tetradotoxin can cause specific symptoms to appear within a quarter of an hour or even earlier.

Food allergy when eating mackerel fish also reminds of itself in the first minutes after the meal. But a person can find out about helminth infection weeks and months later by increased appetite and unexplained weight loss. Although sometimes parasites are accidentally found in various organs, including the liver and brain, and the patient does not even suspect their existence inside the body.

Chronic intoxication, which is possible if a person eats fish caught in an industrial zone for a long time, does not immediately make itself known. If the dose of toxin is small, a person may not notice any symptoms at first. Much later, nausea and weakness may appear, sometimes accompanied by vomiting (this is how the body tries to get rid of the poison, although this is not effective, because the toxins have been circulating in the blood for a long time).

Fish poisoning in a child

All parents want to see their children strong and healthy, and give them fish for lunch or dinner, because it contains substances that are very useful for growth and development, which are not found in meat or milk. Fish is very useful for a child, but only if it is a freshly prepared product from high-quality raw materials.

Unfortunately, we cannot always trace the entire path of the fish to our table, we do not always know its habitat, storage and transportation conditions. But fish is a delicate product and any violations at the storage or preparation stage can cause severe poisoning, which is even more dangerous for children than for adults. After all, a child's body is still in the final stage of formation for a long time after birth. The body's defenses are still too weak to contain infection or intoxication.

Since few people would think of giving exotic fish to children, there is no point in talking about poisoning. Pediatricians also do not recommend giving mackerel fish to children, so food allergies can also be ruled out. Usually, the cause of child poisoning is spoiled fish with a set of bacterial microflora.

And the child's body is not yet able to actively fight the dominance of bacteria, so the symptoms of fish poisoning in children may appear earlier than in adults (within half an hour), and their severity is much higher. Vomiting usually appears first, and the urge is so frequent that it completely exhausts the child in the first day. Not every adult can easily withstand vomiting 10-15 times.

A little later, the baby begins to complain of abdominal pain, and diarrhea begins. The stool becomes watery after a while, but may also have a greenish tint, which once again confirms the bacterial nature of the poisoning.

In case of mild poisoning, the child feels quite well, but the loss of fluid and increased intoxication make themselves known through an increase in body temperature and weakness, as a result of which the child becomes lethargic and begins to be capricious.

If vomiting is frequent and accompanied by severe diarrhea, dehydration occurs at an accelerated rate. The baby's skin turns pale, there is a strong thirst, the pressure drops, and the pulse, on the contrary, accelerates, breathing becomes frequent and heavy, resembling shortness of breath. The amount of urine excreted also decreases, which becomes darker in color (becomes more concentrated).

If nothing is done, the child may develop infectious toxic shock, a condition that is life-threatening for the baby, so at the first symptoms of intoxication, all measures must be taken to reduce the toxic impact on the body.

Forms

Let's look at the main risk factors for fish poisoning depending on the type of fish or the method of its preparation:

• Raw fish poisoning, although not considered a particularly common problem (it is not customary for us to eat raw fish, except perhaps as part of sushi), still leads to unpleasant consequences. Even if it is not an exotic sea or ocean fish, stuffed with its own toxins, and not an inhabitant of polluted bodies of water (although such fish are unlikely to be used in self-respecting Japanese restaurants), there is no guarantee that pathogenic bacteria and parasites have not settled inside the fish at one time.

In fish that lived in fresh water, you can find both small worms (anisakiasis) and tapeworms (opisthorchiasis), which absorb all the useful substances from food and cause inflammatory processes in the intestines. But unfrozen and improperly stored fish can become a source of staphylococci and salmonella.

• Poisoning from dried fish is a more common problem, because it is not a completely finished product. Drying is a special way of preparing fish, in which it turns out moderately salty and quite juicy, unlike dried fish. Undoubtedly, dried fish is a very tasty delicacy, but it often carries the risk of bacterial contamination.

The thing is that salt acts as a preservative and antimicrobial component in fish, and if you put less than the minimum required amount, the product will still start to spoil quickly, after all, dried fish is prepared at insufficiently high temperatures necessary to kill microbes. The temperature regime at which the fish is kept for several days from salting to drying also plays a big role, as does the storage of the finished product. Dried fish cannot be stored for a long time either in the heat or in the cold, remaining juicy and safe.

Although the safety of such a product is still debatable. For example, where is the guarantee that the fresh raw material initially did not contain parasites, whose eggs can survive even during salting and drying, or that the fish was not infected with pathogenic bacteria. Although bacteria can also appear as a result of non-compliance with the technology of preparation and storage of dried fish.

If you buy fish from a stranger, can you be sure that it was caught in a clean, unpolluted water body and does not contain toxins that are dangerous to the body? Hoping that salt will destroy toxins is at least unreasonable.

• The same can be said about poisoning with dried fish. Here, of course, you can add more salt, which will provide a good antibacterial effect, but drying in the heat and long-term storage in inappropriate conditions can reduce all the work to "nothing".

Moreover, drying fish bought at the market or buying ready-made dried or cured fish is dangerous even in the sense that it is unknown under what conditions the processing and drying was carried out, whether the manufacturer adhered to sanitary and hygienic standards or whether there were swarms of flies around the fish offered to us?

Again, there remains the problem of toxins, which is especially relevant if the internal organs and gills, which accumulate the bulk of toxic substances (parasites and some bacteria are also most often hidden there), were not removed from the fish during drying.

• Salting is another favorite way to prepare tasty fish, which will come in handy for any feast, especially with alcohol. But salting is a very delicate matter, which requires a certain concentration of salt solution and sufficient soaking of the fish in brine.

We have to disappoint fans of lightly salted fish, because the finished product can be obtained in two ways, one of which is very popular, but can cause fish poisoning. Lightly salted fish can be obtained by keeping it in a cool place for a long time in a not very strong brine, or by saving time and making the brine stronger, and reducing the salting time. In the latter case, we get a tasty fish, salted near the skin and almost raw in the spine area, often even with blood. After leaving the brine, such fish will spoil very quickly, not to mention the safety of live parasites inside it, if there were any.

How do you know if the fish is salted enough to avoid salted fish poisoning? By the eyes. The eye sockets of a cooked fish should be sunken.

It is also important under what conditions the fish was salted, because if sanitary and hygienic conditions were not observed, the fish could become contaminated with various types of microorganisms at any stage of the preparation process.

Not many people know, but not only high-quality fish is salted. For savvy entrepreneurs, this is a good way to get rid of spoiled goods, because after salting, the unpleasant smell disappears. This is often done with defrosted herring or mackerel, which can no longer be stored for long.

• Smoked fish is especially respected at our celebrations, it is considered an exquisite delicacy, especially when it comes to noble species of fish. But smoking can make fish safe only if all the rules are followed: temperature, amount of salt, holding time, otherwise poisoning from smoked fish cannot be avoided.

And smoking can be different. Cold smoking focuses on the preservative - salt, because only a sufficient amount of it can destroy harmful microorganisms and parasites. Hot smoking involves using less salt, but the fish is additionally subjected to heat treatment. However, such treatment is not enough to prevent the decomposition process for a long time, so hot smoked fish is not stored for long. As we can see, smoking does not make the storage of fish eternal and does not cancel the conditions for its storage in refrigerators.

When processing fish with smoke, there is a risk of forming carcinogenic substances that are harmful to the body. And if you consider that the fish may not even see smoke, but be smeared with a special concentrate that gives it the appearance and aroma of smoked fish, the likelihood of poisoning with chemicals in this case is incredibly high, which is again confirmed by statistics. By the way, on the shelves of retail outlets, the percentage of such smeared fish sometimes even exceeds the content of a product prepared according to all standards.

By the way, smoking is another incredibly effective way to use low-quality raw materials, expired and slightly spoiled goods to your advantage, because the smell of smoke helps to hide all these shortcomings. Do entrepreneurs think about those people who may suffer by eating spoiled fish with a smoky aroma? And here the cause of poisoning is far from improper storage of finished products, because the goods were spoiled even before they were processed.

• The most accessible and popular ways of cooking fish are considered to be frying it in oil, baking in foil, or boiling. Such fish is present on the table not only on holidays, but also on weekdays. Depending on the possibilities, your own catch, fish bought at a retail outlet or from hands serve as raw materials for a tasty lunch or dinner.

It is clear that the safest fish is the one caught by yourself in a clean body of water, which has said goodbye to life just before cooking. But there is one nuance here. If the catch is small and there are enough hungry mouths, then the dish will go away in one go. But in case of successful fishing, all the fish is unlikely to be eaten quickly. And if the remains of fresh fish are not stored correctly (they are not cleaned of entrails and frozen), they will very quickly become unusable. Even if you fry rotten fish, it is unlikely that you will be poisoned by fried fish, because the toxins formed in it cannot be removed by high temperatures.

The same can be said about boiled or baked fish, which can be considered dietary and safe if high-quality fresh or frozen fish was used in the preparation and the finished dish was stored in proper conditions for a limited time, which did not lead to its spoilage.

It is important to understand that poisoning with stale fish, raw or cooked in one of the known ways, is a double danger, because such fish contains two life-poisoning factors: bacteria and toxins. And this is without taking into account possible parasites and toxic substances that could enter the fish's body from the outside.

• Not everyone has encountered such a miracle of nature as butterfish, so named because its tender and tasty meat contains an incredible amount of fat. In fact, butterfish is a generalized name for several types of fish with similar taste qualities and very fatty meat. In addition to the Atlantic butterfish, this includes escolar, seriolella, ruveta, stromate, etc. Unfamiliar names? And this is not surprising, because traders all have the same name for this fish.

It cannot be said that oily fish is something second-rate, although at one time it was presented to us as animal feed. This type of sea creature has its admirers, such fish is even cooked in expensive restaurants, where they know all the nuances of its preparation.

No, this fish is not poisonous. It's just that some of the fats it contains are difficult for the human body to digest, which leads to digestive problems that many people mistake for food poisoning.

In reality, oily fish poisoning is nothing more than severe diarrhea caused by eating a large amount of fat at one time. This problem is usually faced by those who do not know how to cook oily fish properly. In theory, any cooking method is suitable for it, but to avoid frequent visits to the toilet, you need to choose methods such as boiling or grilling. When boiling fish, most of the fat melts into broth, which is then drained. But grilled fish will be much more appetizing, and the fat will simply flow onto the baking sheet during baking.

• Red fish has always been considered a famous delicacy. It would seem that such an expensive delicacy simply cannot be unfit for consumption. Alas, episodes of red fish poisoning say the opposite.

The thing is that delicacy fish varieties with reddish meat are often used to make sushi. It is clear that fresh fish is used, which is not heat-treated. But red fish is not found in local small bodies of water, it is a sea dweller, which means that it will take more than one hour or day before this seafood gets to a store or restaurant. The safety of sushi made from it depends on the conditions in which it is stored and transported.

On the other hand, sushi can now be bought on almost every corner, but the freshness of the finished product is often in doubt. If defrosted fish becomes a breeding ground for bacteria within half an hour at room temperature, then what can we say about sushi, where the same defrosted fish can remain for an hour or two before it gets into the stomach of an unlucky buyer.

You can also disappoint lovers of lightly salted salmon or salmon. You should not hope that at the end of the shelf life, the fish in the store and especially at the market will be disposed of. Most likely, sellers will do everything so that its appearance and smell do not give away the spoilage of the product. If you see a good discount on red fish, think about whether it is caused by critical terms and whether such fish will cause poisoning. After all, salting spoiled fish does not make it safe.

And one more thing. Red fish, although considered to be a salt sea inhabitant, during its migration through fresh water bodies it may well pick up parasites, which it will subsequently transmit to a person who has eaten such a delicacy. Only deep freezing or good heat treatment can get rid of parasites. If neither of these is present, parasites can easily migrate into the human body and migrate inside it.

• Fugu fish is not such a popular delicacy in our region. Nevertheless, there are many people in our country who want to get such a risky pleasure from eating fish with an unusual, "silky" taste. In Japan, where only certain chefs in select restaurants are trusted to cook this fish, and even then this (far from cheap!) pleasure does not always end well. Dozens of deaths associated with eating fish from the pufferfish family are recorded in Japan every year, but this does not stop thrill-seekers with big wallets.

Fugu fish poisoning is not associated with spoilage of the product or its infection with helminths, but with poisoning of the body of the person who ate the fish with a dangerous poison - tetrodotoxin, the effect of which can only be neutralized by a special method of preparation. At the same time, even the cook himself is exposed to mortal danger when handling the fish. And next to the client who wants to try fugu, in Japanese restaurants that respect their name, there is always a specially trained doctor ready to provide emergency assistance at the first signs of poisoning.

The portion of poisonous fish is always very small, because if a large amount of toxin enters the body, it is unlikely that a person will be saved.

Eating puffer fish, especially fugu, is considered one of the riskiest activities that can result in death at any moment. But fatal poisoning is possible not only with fugu or other types of fish that contain poisons. The timeliness of first aid for fish poisoning also plays a major role, and for this you need to know the symptoms that indicate intestinal disorders and intoxication of the body.

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Complications and consequences

Is it worth talking at length about the dangers of fish poisoning, if much has already been said about the possible consequences of eating stale or downright poisonous fish? Probably, a minute of pleasure from eating fish dishes of dubious quality is not worth the torment that may follow.

The vomiting alone is worth something, not to mention the diarrhea, which will not allow you to even leave the house, let alone go to school, work or for a walk. During the first day, a person is literally tied to the toilet. He cannot eat anything, since eating turns into a new episode of vomiting. And stomach pains do not contribute to improving appetite. A person's strength is depleted, because there is no nourishment from outside.

Vomiting, especially in combination with diarrhea, takes away the last of the victim's strength, causing such a complication as dehydration, which in turn leads to disruption of many organs and systems, starting with the central nervous system. The blood becomes thicker and blood circulation slows down. The body suffers from hypoxia (oxygen starvation), and the brain is the first to respond with warning symptoms in the form of dizziness, weakness, attention disorders, etc.

In turn, toxins "finish off" the nervous system, causing dangerous neurological symptoms. And bacteria provoke inflammatory processes in the intestines, which will have to be fought for more than one day. In general, this moment in poisoning is very significant. Sometimes it takes much less time to destroy the cause of food toxic infections than to fight its consequences, because any failures in the functioning of organs do not pass without a trace, and under suitable conditions they can occur again and again.

The most dangerous consequence of fish poisoning is death from paralysis of the respiratory or cardiovascular system. In the case of fugu fish, the probability of such an outcome is too high. But even having eaten a good portion of non-poisonous, but simply rotten fish, a person is at great risk and can die if he does not receive the necessary help in time to cleanse the body of bacteria and toxins.

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Diagnostics fish poisoning

When a person eats fish that is clearly spoiled, as evidenced by a bitter taste and a not very appetizing smell, he knows what to prepare for, and when the first symptoms of poisoning appear, he will certainly be able to name its cause. It is clear that lovers of thrills and overseas delicacies should also be familiar with the possible consequences.

It's another matter if the victim did not suspect that the product was of poor quality, because salting and smoking can hide such small but inconvenient defects as a change in taste and smell. And an allergy to mackerel fish can come as a surprise to many.

The appearance of vomiting and diarrhea in such cases raises a lot of questions. But the first thing to think about when specific symptoms appear 15-60 minutes after eating is what dish or product could have caused the poisoning. If there were fish dishes on the menu, then it is quite possible that the cause of the stomach upset was fish.

In severe cases, an ambulance is called immediately, the doctor will examine the patient at home and take the victim to the hospital. If the situation is not critical, a local therapist is called to the house or goes to him for a consultation. In any case, the doctor conducts a physical examination of the victim with palpation of the abdomen, asks about the possible cause of poisoning, studies information about the patient's existing pathologies. It is necessary to measure body temperature, blood pressure and pulse.

The victim is prescribed tests: clinical and biochemical blood tests will help assess the degree of dehydration (the blood thickens) and the presence of toxic substances, while a stool test will help determine the causative agent of the disease. Sometimes, vomit is examined for this purpose.

A urine test may also be prescribed, which helps to assess the degree of kidney damage due to intoxication, because the kidneys are one of the main filters of the body, which means they suffer the most.

In cases of mild poisoning, instrumental diagnostics are usually not performed. The patient may be offered to undergo gastroduodenoscopy or colonoscopy to determine the condition of the gastric and intestinal mucosa, but these studies are not mandatory.

But if a person is admitted to hospital with severe food poisoning, they may undergo an ultrasound examination of the abdominal organs, and sometimes a rectoscopy. If there are pronounced neurological symptoms, a lumbar puncture is performed.

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Differential diagnosis

The clinical picture of fish poisoning is very similar to other food poisonings, particularly botulism, a disease that doctors single out especially because of the incredibly high danger of botulinum toxin. The latter is found in most cases in canned meat and fish.

The task of differential diagnostics in case of poisoning with fish products is not only to determine the cause of poisoning (eating stale fish or dangerous varieties, consuming other low-quality products, medications), but also to differentiate the pathogens. In addition, acute gastritis, pancreatitis and other gastrointestinal diseases can manifest symptoms similar to poisoning. During pregnancy, toxicosis, which is not associated with the use of spoiled or contaminated products, reminds of itself with the same symptoms.

If there is a suspicion of botulism, it is indicative to conduct electromyography, which determines the biopotential of muscles. In addition, symptoms such as fog before the eyes, a hoarse voice, doubling of objects and a sharp deterioration in vision, slurred speech will also indicate botulism. At the same time, vomiting and abdominal pain with botulinum infections are rare, and the temperature generally remains within normal limits.

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Prevention

The painful symptoms of poisoning and possible dangerous consequences are too high a price to pay for a minute of pleasure. But this does not mean that you should refuse to eat such a healthy dietary product as fish. You just need to be more responsible when choosing fish and fish products for your table.

In order not to make a mistake in choosing fish, you need to follow several simple rules, which, moreover, should become a habit for those who cannot imagine their life without fish:

• You should not buy fish from hands, in dubious markets and in retail outlets where sanitary and hygienic requirements are not observed, and the storage conditions for fish do not meet established standards. If in hot weather the fish is lying on an open counter, and no one has even tried to put it on ice, it will definitely be safer to pass by without making dangerous purchases.

Preference should be given to proven points. Let it be one or two stores where there are quality certificates for the products, you can find out when and where the fish was caught, in what conditions it is stored, and clarify the expiration date of the product.

• It is good if at the time of purchase the fish was not only in the water, but was even still alive. It is not scary if the fish no longer shows signs of life, but it has bright red or burgundy gills, elastic white or slightly pink meat, shiny smooth adjacent scales, clear, transparent eyes, the skin is smoothed out after pressing for a couple of seconds. This indicates that the fish is fresh, its death occurred recently and the decomposition processes have not yet begun. It is worth paying attention to the smell, which is practically absent in sea fish, and in river inhabitants corresponds to the smell of water and mud.

What signs will indicate that the fish is not fresh or even rotten:

• an unusual chemical or foul odor, the smell of ammonia, which will indicate that the fish was caught in a dubious place or has already begun to rot,
• the scales do not shine, are protruding or missing in several places, covered with cloudy mucus,
• the gills are pale and covered with mud,
• the eyes of a raw fish are cloudy and sunken,
• the meat is not dense, does not straighten out when pressed, or returns to its original position very slowly,
• the ribs stick out and when the belly is opened they come away from the meat,
• the entrails are a shapeless mass, easily torn apart, which often happens when the fish has been frozen repeatedly.

• When buying frozen products, it is recommended to always read the certificate for them, which the buyer has the right to see by law. Frozen fish must have documents from which it is easy to find out where and when it was caught. The shelf life of such fish should not exceed six months. Fish with a yellowish coating on the skin or scales, a yellow or gray tint of meat, falling apart after defrosting should seem suspicious. Such signs are typical of products that have spoiled from old age. By the way, they have a corresponding smell. Fish that has been defrosted many times can also fall apart.
• When buying salted and smoked fish, you need to remember that often the raw material for them is actually spoiled fish. Unusually dark meat, white inclusions, an unpleasant smell, too soft meat and damaged skin should alert the buyer. Salted fish and fish prepared by cold smoking should have a dense structure. With hot smoking it is a little more complicated, but rotten fish is often given away by the smell.
• You should be careful when buying raw fish without a head. It may have been chopped off to hide signs of decomposition, because everyone knows that fish rots from the head.
• Some doubts are also raised by fish in the deli section of grocery supermarkets. Usually it is sent there after it has been lying on its sides in the fish section for a long time. Most often, fish with suitable expiration dates is sent to the deli section, and sometimes it is frankly spoiled (after all, no one wants to put their money in for expired fish).
• Discounts in supermarkets are a special matter. Very rarely do they represent a real promotion on a fresh catch with the aim of attracting customers. Most often, promotions hide the opportunity to quickly sell fish that is about to expire. This fish cannot yet be called spoiled, but it is not safe to store it any longer. Such fish should be cooked immediately after purchase.

Promotions in regular stores, where the freshness of products is monitored in most cases by the sellers themselves (they are also responsible for spoilage of goods), under the guise of a promotion, stale goods can be sold, posing a health hazard. The same can be said about market points, where everyone knows who and how much to pay so that the spoiled goods remain on the shelf, and, most importantly, in the case of fish poisoning, it will be almost impossible to prove that the spoiled goods were purchased at this point, because it is not customary to issue receipts at the market.

• By the way, a receipt from a retail outlet that sold a product dangerous to health is the only way to hold unscrupulous traders accountable. Therefore, it should always be requested, checking that it contains the name of the fish and the date of sale.
• You need to be careful when buying and eating exotic fish. If you risk it yourself, at least do not endanger the lives of your children. The usual local fish is no less healthy and tasty if it is cooked correctly, but it is safer than overseas delicacies, to which our body is not accustomed, the result of which will be either poisoning or an allergic reaction.
• Fishermen are advised to adhere to the ban on fishing during spawning, since it is during this period that the largest amount of hazardous substances accumulate in the fish's body.
• It is recommended to use fresh fish caught by yourself or bought in a store within 24 hours. Moreover, it should be stored in water (while alive) or in the cold. The remaining fish should be frozen, after gutting and removing the gills. But it is not recommended to store fish in the freezer for months. For long-term storage, lower temperatures are needed, not provided for in household refrigerators.
• Fish should be stored in film, preventing it from coming into contact with other food products. Ideally, a separate knife and cutting board should be used to prepare fish for cooking or storage.
• If frozen fish was purchased, but it defrosted while it was being brought home, it cannot be frozen again. The defrosted product must be cooked within a couple of hours.
• It is necessary to pay attention to sufficient heat treatment of fish, especially during frying and baking. It is impossible to eat fish meat with blood or poorly fried, because this way you can easily let internal parasites into your body.
• You also need to salt the fish carefully, not sparing the salt and keeping it in the brine for a sufficient amount of time. When drying fish, the amount of salt is also very important, but you should not forget about the sanitary conditions in which the fish will be dried. Flies, the main carriers of infection, love raw fish, and salt is no obstacle for them. But spoilage of the product is guaranteed when flies lay eggs on it.

Before serving the prepared fish to guests or family, you should first try it yourself. The presence of a foreign suspicious smell and taste indicates that the dish is unsuitable for food. This way, you can prevent mass fish poisoning and not become the culprit of other people's suffering.

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Forecast

Fish poisoning is a rather dangerous situation that requires urgent measures to prevent the spread of toxins in the body and damage to the central nervous system. If, in the case of poisoning with a stale product, the symptoms of intoxication increase gradually, and a person has enough time to take appropriate measures, then in the case of poisoning with toxic types of fish, there is very little time to provide first aid.

With timely treatment, poisoning by rotten fish has a generally favorable prognosis, although treatment in severe situations will be quite long. But it is better not to joke with exotic types of fish, because the poison they contain very quickly gets into the blood, which often leads to sad consequences - damage to vital organs, and sometimes even death.

The worst prognosis is for poisoning with fugu fish and botulism. In the first case, even timely assistance does not guarantee saving a person's life. Even in such a situation, the mortality rate exceeds 60%. Poisoning with botulinum toxin requires the immediate introduction of a special serum, and if there is none, the probability of a fatal outcome is extremely high. And although such a delicacy as fugu is not popular in our area, botulinum toxins can be considered ubiquitous, so they can be found in both imported and domestic canned fish. At the same time, there are facts indicating that botulism can be contracted even after eating dried fish, although previously canned fish was blamed for everything.