Insect bites Health Dictionary

Animal bites are best treated as puncture wounds and simply washed and dressed. In some cases ANTIBIOTICS may be given to minimise the risk of infection, together with TETANUS toxoid if appropriate. Should RABIES be a possibility, then further treatment must be considered. Bites and stings of venomous reptiles, amphibians, scorpions, snakes, spiders, insects and ?sh may result in clinical effects characteristic of that particular poisoning. In some cases speci?c ANTIVENOM may be administered to reduce morbidity and mortality.

Many snakes are non-venomous (e.g. pythons, garter snakes, king snakes, boa constrictors) but may still in?ict painful bites and cause local swelling. Most venomous snakes belong to the viper and cobra families and are common in Asia, Africa, Australia and South America. Victims of bites may experience various effects including swelling, PARALYSIS of the bitten area, blood-clotting defects, PALPITATION, respiratory di?culty, CONVULSIONS and other neurotoxic and cardiac effects. Victims should be treated as for SHOCK – that is, kept at rest, kept warm, and given oxygen if required but nothing by mouth. The bite site should be immobilised but a TOURNIQUET must not be used. All victims require prompt transfer to a medical facility. When appropriate and available, antivenoms should be administered as soon as possible.

Similar management is appropriate for bites and stings by spiders, scorpions, sea-snakes, venomous ?sh and other marine animals and insects.

Bites and stings in the UK The adder (Vipera berus) is the only venomous snake native to Britain; it is a timid animal that bites only when provoked. Fatal cases are rare, with only 14 deaths recorded in the UK since 1876, the last of these in 1975. Adder bites may result in marked swelling, weakness, collapse, shock, and in severe cases HYPOTENSION, non-speci?c changes in the electrocardiogram and peripheral leucocytosis. Victims of adder bites should be transferred to hospital even if asymptomatic, with the affected limb being immobilised and the bite site left alone. Local incisions, suction, tourniquets, ice packs or permanganate must not be used. Hospital management may include use of a speci?c antivenom, Zagreb®.

The weever ?sh is found in the coastal waters of the British Isles, Europe, the eastern Atlantic, and the Mediterranean Sea. It possesses venomous spines in its dorsal ?n. Stings and envenomation commonly occur when an individual treads on the ?sh. The victim may experience a localised but increasing pain over two hours. As the venom is heat-labile, immersion of the affected area in water at approximately 40 °C or as hot as can be tolerated for 30 minutes should ease the pain. Cold applications will worsen the discomfort. Simple ANALGESICS and ANTIHISTAMINE DRUGS may be given.

Bees, wasps and hornets are insects of the order Hymenoptera and the females possess stinging apparatus at the end of the abdomen. Stings may cause local pain and swelling but rarely cause severe toxicity. Anaphylactic (see ANAPHYLAXIS) reactions can occur in sensitive individuals; these may be fatal. Deaths caused by upper-airway blockage as a result of stings in the mouth or neck regions are reported. In victims of stings, the stinger should be removed as quickly as possible by ?icking, scraping or pulling. The site should be cleaned. Antihistamines and cold applications may bring relief. For anaphylactic reactions ADRENALINE, by intramuscular injection, may be required.... bites and stings

See BITES AND STINGS; RABIES.... dog bites

Of cats, dogs, fish, domestic and other animals. Treatment as for RABIES. For weever fish sting the best treatment is hot water. For bites of insects, see INSECT BITES. ... bites

Oils: Lavender, Pennyroyal, Cloves, Thyme. Apply to exposed areas. Avoid contact with mucous membranes.

Popular Indian: 2-3 drops oil Citronella on handkerchief and dabbed behind ears, on neck, hair, etc. Garlic repels all insects and beetles. Cedarwood essential oil kills houseflies, mosquitoes and cockroaches in concentrations of less than 1 per cent. (Central Institute for Medicinal Plants, Lucknow) ... insect repellents

Any injury inflicted by the mouthparts of an animal, from the puncture wounds of bloodsucking insects to the massive injuries caused by shark or crocodile attacks. Teeth, especially those of carnivores, can inflict severe and widespread mechanical injury. Severe injuries and lacerations to major blood vessels can lead to severe blood loss and physiological shock. Serious infection may occur due to bacteria in the animal’s mouth; and tetanus is a particular hazard. In countries where rabies is present, any mammal may potentially harbour the rabies virus and transmit it via a bite. Medical advice should be sought for all but minor injuries or if there is a possibility of rabies. Treatment usually includes cleaning and examination of the wound. The wound will usually be left open and dressed. Preventive antibiotic drug treatment and an antitetanus injection may also be given. Antirabies vaccine is given, with immunoglobulin, if there is any possibility that the animal is infected with the rabies virus. (See also bites, human insect bites; snake bites; spider bites; venomous bites and stings.)... bites, animal

Wounds caused by one person biting another. Human bites rarely cause serious tissue damage or blood loss, but infection is likely, particularly if the bite is deep. There is a risk of tetanus infection. Transmission of hepatitis B, herpes simplex, and AIDS by a bite is a theoretical hazard.... bites, human

See insect bites.... flea bites

Bites of small, long-legged sandflies, found in many warm climates, which can transmit disease to humans.

In tropical and subtropical areas they transmit leishmaniasis.

In parts of Asia and the Mediterranean, they transmit sandfly fever, an influenza-like illness.

In the western Andes, they transmit bartonellosis, different forms of which cause either joint pain and fever, or a rash.... sandfly bites

Nearly all spiders produce venom, which they use to kill their prey.

However, only a few species, such as the black widow in North America, are harmful to humans.

Antivenoms are available for many dangerous spider bites.... spider bites

Reactions produced by the sting of insects such as bees and wasps.

Venom injected by the insect contains inflammatory substances that cause local pain, redness, and swelling for about 48 hours. Any sting in the mouth or throat is dangerous because the swelling may obstruct breathing. About 1 person in 200 is allergic to insect venom, and a severe allergic reaction can occur, leading to anaphylactic shock. A procedure known as hyposensitization is sometimes recommended for such people.

If the symptoms of anaphylactic shock develop, it is essential to seek emergency medical treatment. Any person who is known to be hypersensitive to bee or wasp venom should obtain and carry an emergency kit for the self-injection of adrenaline (epinephrine).... insect stings

Mosquitoes are flying insects found throughout the world. The females bite humans or animals to obtain blood, which they need to produce eggs. The males do not bite. A doctor should be consulted if there is a severe skin reaction to a mosquito bite.

As well as being irritating, mosquito bites can also transmit diseases. The main disease-transmitting mosquitoes belong to 3 groups: ANOPHELES (which transmits malaria), AEDES (which carries yellow fever), and CULEX (which transmits filariasis).

Preventive measures should be taken in any area where mosquitoes are rampant. The most effective measures are wearing long sleeves and socks, placing mosquito screens over windows, and using insect-repellent sprays or slowburning coils that release insecticidal smoke. Mosquito nets should be placed over beds. (See also insect bites; insects and disease.)... mosquito bites

Most snake bites are by nonvenomous species. Venomous snakes are found mainly in the tropics; the only species native to the is the adder.

The effects of a venomous bite depend on the species and size of the snake, the amount of venom injected, and the age and health of the victim. A bite from an adder or other viper typically causes immediate pain and swelling at the site, followed by dizziness and nausea, a drop in blood pressure, an increase in heart-rate, and internal bleeding.

Antibiotic drugs and tetanus antitoxin injections are given for all bites to prevent infection and tetanus.

An injection of antivenom is also given for a venomous bite.

With prompt treatment, most victims recover completely.... snake bites

The bites of tsetse flies, which are found in Africa, can be painful. The flies, resembling brown houseflies, spread sleeping sickness.... tsetse fly bites

A cause of myiasis.... tumbu fly bites

The injection of venom by certain animals via their mouthparts (bites) or other injecting apparatus (stings). Venoms are often carried to discourage predators, and are sometimes used to kill or immobilize prey. It is rare for a venomous animal to attack a person unless it has been provoked or disturbed. Specific antivenoms are available to treat many, though not all, types of animal venom. (See also insect stings; jellyfish stings; scorpion stings; snake bites; spider bites.)... venomous bites and stings

n. a member of a large group of mainly land-dwelling *arthropods. The body of the adult is divided into a head, thorax, and abdomen. The head bears a single pair of sensory antennae; the thorax bears three pairs of legs and, in most insects, wings (these are absent in some parasitic groups, such as lice and fleas). Some insects are of medical importance. Various bloodsucking insects transmit tropical diseases, for example the female Anopheles mosquito transmits malaria and the tsetse fly transmits sleeping sickness. The bites of lice can cause intense irritation and, secondarily, bacterial infection. The organisms causing diarrhoea and dysentery can be conveyed to food on the bodies of flies. See also myiasis.... insect