Harmless in appearance and deadly - the brown recluse spider. Brown Spider Precautions against Potential Hazards

Brown spider the hermit (Loxosceles reclusa, lat.) is one of the representatives of araneomorphic spiders. This species is most common in the eastern United States. From there he migrated in the southern and southwestern directions of this continent, and there is also evidence that this type was also introduced to Australia. The most suitable conditions for its functioning are subtropical zone, Mediterranean. The venom and bite of the recluse spider is extremely poisonous and dangerous to humans.

Appearance

The brown recluse spider has several main features. The first of these is three pairs of eyes, while other arthropods have four. It has white spots at the joints of the legs, as well as a random flesh-colored web with an extremely sticky structure.

Danger to humans

The bite of a recluse spider is considered one of the most dangerous for humans, because its venom is distinguished by its toxicity, and the bite itself is barely noticeable on the skin (as a rule, it resembles an injection from an ordinary needle).

Hunting methods

For the most part, the brown recluse spider is not an aggressive member of its species. He himself attacks people very rarely, only in cases of obvious danger from a person, when he accidentally disturbed his mink. Most often this happens in bed, in shoes or some closets, among various rubbish. The spider regards such actions as an invasion of its territory. The result is a human bite. Typically it occurs on the arms, neck or lower abdomen.

Signs of a Brown Recluse Bite

After a spider bite, an unpleasant burning sensation or noticeable tingling of the skin may appear in this area. Further symptoms develop depending on how much poison was introduced by the spider. In cases where it was enough large number- after five to six hours the wound swells and turns into a blister.

Intestinal disorder.
Heart problems, tingling and pain.
Symptoms of a cold include runny nose, cough, loss of strength and broken bones.

After 2-3 days, the ulcer from the spider bite on the skin bursts and a non-healing ulcer forms in this place. Next, tissue necrosis appears.

This is due to the fact that the venom of this spider is saturated with the enzymes protease and alkaline acid phosphatase. If necrosis has begun, wound healing may take several years.

First aid for a brown recluse spider bite

A person affected by this arthropod urgently needs help. The first action that is carried out after calling an ambulance and before its arrival is washing the wound with soapy water. Next you need to place the ice in cloth napkin and place on the bite (for 10-15 minutes). This procedure requires several repetitions. This is done because the cold slows down the action of the toxins contained in the poison.

When doctors arrive, the first thing the victim is given is antihistamines. The doctor is also advised to be sure to catch the culprit of the incident and place him in a jar with a tight lid.

List of medications that should be taken in case of a brown recluse spider bite:

Drugs with anti-inflammatory properties.
Dextran for poison detoxification.
Antimicrobial ointments and drugs (for example, Dapsone).
Antibiotics as prescribed by the attending physician.

Precautions

In areas where it is expected to live brown recluse You need to dust off your clothes, as well as your shoes.
Shake and check bedding.
When working in the garden or around the house in general, you must use gloves; walking barefoot is prohibited.
Be more careful when carrying stones and other household tools.

Spiders (arachnids) are silent killers that, if attacked, cause instant death to their victim. Patient and calculating arachnids (all spiders belong to this class) weave trapping, killing webs from invisible sticky threads. Up to 30 thousand species of spiders are known. They live next to humans - in houses, forests, fields, and ponds. And, of course, a spider bite is not uncommon, especially if a person is in the habitat of spiders.

All spiders are poisonous. Venom glands are located on two head appendages - chelicerae. They need poison to kill and digest their prey. The main prey is insects. Some tropical spiders have a web with a diameter of 2 m and can even interrupt the flight of a small bird. They feed on frogs, mice, small birds, fish and even their own brothers - cannibalism among spiders is quite common. Most spiders are not capable of causing significant harm to humans. Although the venom is strong, its small amount and poorly developed injection mechanism limit the number of species dangerous to humans. The only dangerous ones for people are those that can pierce the skin. The most common species include karakurt (black widow), tarantula, scorpion, hermit spider, cross spider, tarantula spider, and house spider.

spider bite the next day

Most spider bites have general characteristics, such as a small blister in the middle, swelling and swelling surrounding the bite site, and large redness in a circle. On the outer side of the bite site the redness is paler. It's important to note that a spider can only bite once, so if you have multiple bites, it's probably someone else who bit you other than a spider, or multiple spiders bit you at once. A typical spider bite goes away within a few days and, in most cases, does not require special attention.
However, if the bite site looks different - a large bubble appears, bright redness quickly spreading to the sides, blue discoloration of large areas of the skin - these are serious signs that you need to react to immediately and contact a medical facility immediately.
In the photo you can see the differences - what a bite from a safe spider looks like and a bite that is dangerous to health.

What to do if bitten by a spider

First of all, don't panic! Although all spiders look scary, there are only about 12 species whose bite has a serious impact on people or animals. The two most dangerous are the black widow spider and brown recluses.
Check the wound. After a bite, pay attention to the site of the bite - whether there is redness, swelling and burning pain. There may be abdominal pain, vomiting, headache, fever, dizziness. The most dangerous reactions are difficulty breathing and shock. If there is anything more than just a bite mark, slight redness and pain, you should call ambulance or consult a doctor.
Spider identification - if possible and safe. Some spider bites require serious treatment, including antitoxins. If you are unable to identify the spider, this will be helpful in determining appropriate treatment. It will help a lot if you can catch the spider in a jar or box (just remember to be safe). Or at least take a photo of it and show the photo to the doctor.

First aid for a spider bite

To reduce blood flow in the affected area, it is necessary to secure the arm or leg with a belt or scarf - as if there was a fracture. This will prevent the poison from quickly spreading into the blood and spreading throughout the body.
Wash the bite with soap and water. Regardless of whether the spider is harmless or poisonous, it should be washed thoroughly as soon as possible. Even ordinary spider If bitten, it can cause infection in the wound.
Apply a cold compress or ice to the bite site.
Drink plenty of fluids - this will ensure that the poison is quickly eliminated through the kidneys.
Take a pain reliever - for example, analgin or ibuprofen.
And also an antihistamine that will reduce allergic symptoms - itching, burning, rash.

If you suspect you have been bitten poisonous spider, you can apply a tight bandage above the bite if it is on an arm or leg, making sure you do not completely cut off the circulation.

The goal is to slow the spread of the venom, not stop blood flow to the extremities. If the bite is on another part of the body, apply ice and get to a medical facility immediately. Hospitalization is required for most of these types of bites.

Recluse spider bite

One of the four spiders whose bite poses a danger to humans - recluse spider. The brown recluse is generally not aggressive and generally bites people as a means of defense mechanism, usually when a person's leg or arm accidentally gets too close.

The brown recluse has a clear fiddle pattern on its back in the midsection of its body - pictured.

The venom of the recluse spider contains powerful cytotoxins and hemolytic enzymes that destroy red blood cells. Although the sting is not usually painful at first, there is a burning sensation similar to a bee sting for the first few minutes after the sting.
A small white blister may also appear at the site of the bite.

Additional symptoms usually develop two to eight hours after a recluse spider bite. Sometimes it takes up to 12 hours until symptoms of the bite develop. Signs:

severe pain at the site of the bite
severe itching
nausea
vomit
fever
muscle pain

Local symptoms

Initially, you may see slight signs of redness at the site of the spider bite.

In most cases, the skin at the site of the bite then hardens and scar tissue may take several days to form. More severe local reactions also occur and can cause blistering, discoloration of the skin, and necrosis of the skin area.

Treatment

Because The reaction to a recluse spider bite can be sudden and severe; it is necessary to contact a specialist to prescribe treatment. A visit to the doctor should not be delayed until symptoms appear; see a doctor as soon as possible.
If possible, the spider should be caught and brought to a doctor or emergency room for evaluation.

There are no known antivenoms for brown recluse bites, so your doctor may prescribe painkillers, antihistamines to relieve itching, or recommend icing the bite to reduce pain and swelling.

Cross spider bite

The cross is a small creature harmless to humans that lives quietly, hunting insects that fall into their nets. The sharp poisonous fangs of the spider are primarily a tool for hunting and serve to protect it from other spiders. The victim, falling into the trap, is quickly paralyzed by the poison, and then the spider devours it.
The cross spider looks quite harmless - it is distinguished by its characteristic cross pattern on its back. The color varies from green to gray, depending on the habitat. The cross is very common - it lives almost everywhere.

A human bite can only be accidental. Their teeth are not able to damage hard skin, but thinner areas of the body are not a problem. Most often, this situation can arise while walking in the forest, picking mushrooms or traveling. Cross plants grow quickly and can reach impressive sizes in late summer.

They stretch webs of webs between trees at a height human face. An inattentive mushroom picker falls into the network being laid and completely destroys it. Then the insect, willy-nilly, tries to escape or hides under clothing. IN at the moment, we can accidentally crush an insect and then the spider bites.

Sometimes such situations occur during sleep. Spiders are nocturnal creatures and often move around in search of good places for hunting. A sleeping person, feeling a slight tingling sensation on his body, instinctively trying to scratch himself, crushes it, exposing himself to a bite. Erythema or swelling may occur on the body in the area of the spider bite. Usually these symptoms go away on their own.

The poison of the cross does not cause any harm to humans. However, people with allergies or sensitive to spider toxins should consult a doctor.

Tarantula bite

The bite of a tarantula (Lycosa, Theraphosidae) does not pose a danger to humans, but may be accompanied by pain and swelling. After being bitten, the animal performs a defensive maneuver, while shedding hairs from its abdomen. Small hairs getting into the eyes and skin cause pain and urticarial rash. A type of tarantula is the tarantula spider.

Tarantula spider bite

There are 400 species of tarantulas of different colors. From cobalt blue to gray or dark brown, sometimes black. The tarantula reaches sizes from 9-10 to 17-23 cm, although its body is no more than 10 cm. The rest is on the legs.
Tarantulas live a very long time - from 25 to 40 years, but this depends on the gender of the spider. He is one of the most terrible spiders (outwardly) - his weight is 80 grams! The tarantula spider does not spin a web like other spiders, but pursues prey with its long legs and paralyzes it with venom. It feeds on small insects - grasshoppers, beetles, spiders, and even small lizards.

Incredibly, the spider has eight eyes - two in front and two each on the left, right side and back! They usually dig holes in the ground and build a house there.

Tarantulas are poisonous, but most types of venom are not strong enough to seriously harm anyone.

A tarantula bite can be compared to a wasp or bee sting. In most cases, this is harmless, although a person who has an allergy may react like a bee sting.
IN lately some began to keep the tarantula spider as a pet. A human bite can occur due to negligence when a spider tries to escape from a terrarium.
First aid for a tarantula bite is no different from other bites - you should consult a doctor if you have an allergy or signs of wound infection.

Karakurt bite

Karakurt (Latrodectus tredecimguttatus) - a poisonous spider, lives in Moldova, Crimea, Central Asia. Females that have a pair of tubular poisonous glands located on the upper jaw are dangerous to humans. The poisonous segment (chelicerum) ends in a movable sharp claw with an opening for the duct of the poisonous gland. The female has a spherical dense black belly with reddish spots. The length of the karakurt is about 10 mm.

Symptoms of poisoning with karakurt poison

After a bite, a small, quickly disappearing spot is formed. After 10-20 minutes, severe pain develops at the site of the lesion, which spreads to the abdomen, lower back, and chest. Severe mental agitation, headache, dizziness, suffocation, nausea, vomiting, weakness, shortness of breath, cyanosis, tachycardia, arrhythmia are observed. Severe drooling may begin. Possible respiratory arrest.

Black widow bite

The black widow spider (Latrodectus mactans) of the genus Latrodectus lives in the United States. The females of this species are very large: the paw span reaches 5 cm, and the body length is 1.5 cm. There is a red hourglass pattern on the black back.

Males are smaller, with a white mark on the back, the small size of the venomous apparatus and mild aggressiveness make them practically harmless to humans. When disturbed, they fall to the ground, fold their paws and pretend to be dead. Female black widows are venomous from the moment they are born. If they are guarding laid eggs or feel threatened, they prefer to attack. Spiders use their venom to paralyze prey, from which they then suck the hemolymph.

The period of post-copulatory passivity of the female allows the male to escape from his partner if she is not very hungry. If the female is hungry, then after mating she eats the “wife”, which is why she is called a “widow”.

Karakurt poison - protein with molecular weight 130 000. Under the influence of poison in presynaptic membranes nerve cells Ion channels are formed through which Ca 2++ ions enter the cell. Under the influence of the toxin, exocytosis of synaptic vesicles is facilitated and the release of gamma-aminobutyric acid (GABA), norepinephrine, and acetylcholine is enhanced.

Changes in intracellular homeostasis and an increase in the content of biologically active substances in the blood affect the functional state of the nervous and cardiovascular systems.

In case of poisoning with karakurt poison, clinical manifestations develop within 30 minutes. The victim usually feels the sting and describes it as a "puncture". In the area of the spider bite, severe pain is noted, erythema and increased local sweating gradually increase.

Karakurt bite degree

When bitten by a black widow, there are three degrees of severity of the disease.

I degree; moderate pain at the site of the bite, no general clinical manifestations of intoxication, all laboratory parameters are normal.
II degree: muscle pain in the bitten limb. Pain spreading to the abdomen when a leg is bitten or to the chest when an arm is bitten. Profuse sweating at the site of the bite. Vital important indicators normal.
III degree: generalized muscle pain in the back, chest, abdomen. Strong mental agitation. Headache, dizziness, suffocation, nausea, vomiting, weakness, shortness of breath, cyanosis, arterial hypertension, tachycardia, arrhythmia. General profuse sweating. Severe drooling. Possible respiratory arrest. Blood tests show increased levels of creatine phosphokinase (CPK), leukocytosis, and proteinuria. In the absence of treatment, the maximum severity of symptoms lasts for 12 hours, the duration of intoxication is 48-72 hours.

in the photo on the left - the bite at the beginning, on the right - on the 3rd day

Muscle spasms and muscle tension in the anterior abdominal wall sometimes cause misdiagnosis of peritonitis and unnecessary laparoscopy.

Scorpion sting

The scorpion spider (Centruroides sculpturatus) is a poisonous spider widely distributed in the world. In Russia it lives in southern latitudes. A structural feature of the scorpion, unlike other arthropods, is the presence of pedipalps with claws; at the end of the abdomen there is a curved sharp sting where the duct of the poisonous glands opens. The most dangerous is the black scorpion, its size is 50-100 mm.

Scorpion venom binds to sodium channels cell membranes, causing repeated activation of neurons. This is accompanied by an extension of the neuronal action potential at the synapses of the autonomic nervous system, which leads to an increase in the blood levels of catecholamines, renin and aldosterone.

Symptoms of poisoning from a scorpion sting

The bite causes severe pain, which quickly spreads along the nerve trunks. The victim screams in pain, develops severe weakness, and has convulsions. separate groups muscles, increases blood pressure, the body becomes covered with cold, sticky sweat. A urticarial rash appears in the bite area. In severe cases, motor agitation develops, arterial hypertension turns into hypotension, tachyarrhythmia, ventricular extrasystoles, vomiting, profuse sweating, priapism, and salivation occur.

Increasing visual impairment, ptosis, involuntary contractions of the tongue muscles are noted, and speech becomes slurred. Within 2-3 hours after the poison is introduced into the body, breathing becomes impaired and pulmonary edema develops. Death occurs due to the phenomena of increasing acute cardiovascular and respiratory failure.

When assessing the degree of toxicity of arthropod venom, the following was noted:

Spider bite treatment

To reduce the spread of venom from the bite site throughout the body, immobilization of the limb is indicated. The pain is relieved by performing a novocaine blockade, and painkillers are administered: non-narcotic and narcotic analgesics. Cold is applied to the bite area.

Hormones, antihistamines are administered: H1-receptor blockers (promethazine (diprazine), chloropyramine (suprastin), etc. and H2-receptors (cimetidine, ranitidine (acylok), etc., vitamins. When excited, benzodiazepines are prescribed. When a karakurt bite, an anti-karakurt drug is administered subcutaneously serum. In severe cases, horse immunoglobulin (IgG) is administered. Antitoxin (from horse serum) prevents the venom from binding to presynaptic membranes and remains effective even 46 hours after the bite.

When a scorpion stings, calcium channel blockers and ACE inhibitors are prescribed. Propranolol (anaprilin) effectively and quickly stops tachyarrhythmia, but does not improve hemodynamic parameters. In case of respiratory depression, oxygen is supplied; in case of acute respiratory failure, artificial pulmonary ventilation (ALV) is performed.

The brown recluse spider, whose name in Latin is Loxosceles reclusa, is a highly poisonous arthropod.

The consequences of its bite can be extremely dangerous to human health. In this article we will look at what a recluse spider looks like, the dangers of its bite, and how to help a victim of its poison.

Appearance and dimensions

Recognizing a recluse spider is relatively easy:

Despite the name, the body of Loxosceles reclusa is not always brown in color - it can be gray or brownish-yellow. The size of females in this species is slightly larger than the size of males.
Representatives of this species of spider have an unusual marking - a brown spot in the shape of a violin. This is a feature of adult hermits, but sometimes it is also present in younger individuals.
Did you know? Arachnophobia is the fear of representativesa squad of spiders. This phobia is one of the most common in the world and affects approximately 10% of men and 50% of women. The severity of the phobia can vary in one direction or another.
Clear difference brown recluse from other arachnoids in the number of eyes. He has only three pairs of them, while other spiders have four, i.e. 8 pieces.
In a calm state, the hermit’s paws are placed on the sides of the body, but in case of alarm, he immediately takes a protective position: he pulls his front legs under him, raises his pedipalps and straightens his hind limbs.
The back color of adult Loxosceles reclusa varies from tan to dark brown.
The belly and legs are evenly colored, without stripes or spots. The legs are long and thin, without noticeable spines. The abdomen is covered with fine, short hairs that, when viewed without magnification under a microscope, may appear like soft fur.
The joints of the limbs are slightly lighter in color than the legs.

Where does it live?

Loxosceles can live almost all over the world in warm, tropical regions. This species is common in some areas of the United States of America (Southern California, Colorado, New Mexico).

The appearance of these spiders in other countries can happen by accident - they are transported along with cargo by air or across the ocean. They have not yet been seen in Russia and Ukraine. In nature, brown recluse spiders live outdoors under rocks, logs, and woody debris.

The spider can also live in the same room with people. Hermits are resilient enough to survive winters in unheated basements or stifling summer heat in attics, going for months without food or water.

During the daytime, brown recluse spiders usually hide in dark, secluded areas, living up to their nickname. Adult females rarely travel far from their shelter, while males and young females are more mobile and prone to long-distance travel.

Video: about the recluse spider They are the ones who often get into shoes, clothes or beds at night and bite people when accidental contact between the spider and a person occurs.

Sometimes Loxosceles reclusa can be seen during the daytime - they move along the floor, walls and other open surfaces. This behavior may be caused by hunger, pesticide use, or other factors.

How to hunt and what to eat

Loxosceles reclusa hunts at night, catching insects. It does not use a web to capture prey - webs on walls, ceilings, bushes or trees almost always belong to harmless spiders.

Their presence in the house is also unpleasant for many people, but these spiders also prey on brown recluses, thereby bringing benefits.

Loxosceles reclusa is a small spider, does not produce hunting nets, so it hunts its prey in the classic way: it catches up, attacks, injects poison and immobilizes it, killing the victim with poison.
The venom of the brown recluse is lethal to insects - it is very toxic substance, the nature of which is not fully understood. Loxosceles reclusa hunts only on small insects, whose dimensions are much smaller than his own.

Did you know? With the exception of one family (Uloboridae), all spiders are poisonous. They use venom to obtain food and when they bite their prey, they squeeze their venom glands, sending the venom through their fangs into the victim's body. Spider venom paralyzes prey.

Reproduction

Spiders lay their eggs on a bed of silk, which they prepare immediately after mating. As soon as the clutch is finished, the female covers it a large number cobwebs, which makes the cocoon dense and waterproof. Cocoons look like whitish round bags, the size of which does not exceed 7–8 mm.

Each cocoon contains about 40–50 eggs. After hatching, the baby spiderlings grow, gradually increasing in size, molting five to eight times as they mature before reaching sexual maturity.
Loxosceles reclusa become adults approximately a year after birth and live from 2 to 4 years. Females lay up to 5 egg cocoons throughout their lives. Infestation levels of these spiders in homes vary greatly, from the presence of one or a few specimens to several hundred.

Consequences and help with a bite

Like other spiders, the brown recluse is not aggressive. The majority of accidents occur if a person accidentally crushes the spider and the arachnoid comes into contact with bare skin.

Some people can be bitten in bed, other bites occur when moving things and pieces of furniture, or when a person puts on clothes that the spider has recently chosen for its daytime hiding place.

Loxosceles reclusa have very small mandibles and cannot bite through clothing. Initially, the bite is painless. Often the victim does not become aware of the bite until the bitten area becomes red and swollen 3 to 8 hours later.
Most spider bites remain localized and recovery occurs within 3 weeks without serious complications or the need for medical intervention.

In other cases, the victim may develop a necrotic lesion, which appears as a dry, bluish patch of skin with jagged edges, a pale center, and peripheral redness.

Often there is an ulcer within the lesion. As the venom continues to destroy tissue, the wound may grow larger over several days or weeks.

If subcutaneous fat necrosis has begun, it may take up to three years. Complications include local nerve damage and secondary infection. A necrotic ulcer leaves a deep scar after healing.

Often bites in the early stages (in the first 72 hours) cause people to:

fever;
chills;
dizziness;
rash;
vomiting;
weakness;
headache;
myalgia;
arthralgia;
maculopapular rash and leukocytosis.

Sometimes hemolytic anemia, hemoglobinuria and renal failure develop, which can lead to death. The wound must be washed, a sterile bandage and a cold compress applied.

Important!Severe reactions to Loxosceles reclusa venom are more common in children, the elderly, and patients in poor health.

The affected limb should be immobilized, it should be given an elevated position, and if necessary, analgesics and antibiotics should be administered. Anti-spider poisoning serum is effective but not approved for use in all countries. The drug can be used only after the inflammation has subsided.

Difficulties in diagnosis

Spider bites are difficult to diagnose even for doctors. It is especially difficult to do this, relying only on appearance wounds.

Externally, a necrotic wound is very similar to the consequences of other diseases:

bacterial and fungal infections;
gangrene;
diabetic or peptic ulcer disease;
outbreak of the bacterial infectious disease Staphyloccus aureus.

This post is definitely not for the faint of heart, because below you will see a photo report of what it is like to be bitten by a brown recluse spider. This is just tough... The following is the author's text.

The first thing I discovered was the leg of something strange, after I woke up from the feeling that someone had bitten me

Most likely, a brown recluse spider crawled into the bed and when I turned around, it bit my leg at the moment I crushed it. Here he is...

Day 1. It seems like nothing, but it’s in the photo. It felt like pain akin to having boiling water poured on me from the inside. I decided not to lie down, but to act

A little later... I felt the toxin spreading under the skin, I had difficulty controlling the muscles in this place and the bite site itched terribly.

I went to the doctor. He prescribed medications, recommended compresses and ointments and the like. This is what appeared by the time I ended up at the doctor.

Day 2. I woke up with a spot like this. The pain was 7 on a 10 point scale.

Gradually everything began to inflate. Plasters? I don't know why I stuck it...

5 days passed... The blisters burst and I went to the doctor

A day has passed and everything is new... Bruises? These are not bruises, but dead tissue

Just a little more. Necrosis is visible, but it’s better

Gangrenous ecthyma.

Necrotizing cabbage soup and vasculitis. Necrotizing fasciitis.

Pyoderma gangrenosum.

Polyarteritis nodosa.

Treatment

For effective treatment For most bites, only supportive measures are sufficient.

Mild localized reactions are treated by applying ice, cold, wet compresses, keeping the bite site elevated, and prescribing mild analgesics. Cold limits sphingomyelinase D. Necrotic skin areas require routine local measures to treat wounds and ulcers. Surgical debridement is usually not necessary.

■ Antibiotics and tetanus toxoid are prescribed according to indications.

To prevent severe necrosis, dapsone is prescribed at a dose of 50-100 mg/day orally.

■ Data on the use of systemic steroids are conflicting.

Nuances

A sufficiently high degree of suspicion for a bite is required to make an appropriate diagnosis.

■ Bites brown recluse spider may cause a severe reaction of dermal necrosis, which can be mistaken for other systemic diseases.

The characteristic dark violin-shaped marking is located on the back of the spider. The wide base of the “violin” is located closer to the head, and the neck of the “violin” points in the direction of the abdomen.