1. Was the accident caused by a POISONOUS or VENOMOUS animal? |
ORAL INTOXICATION due to the consumption of poisonous animals or their roe
Poisonous animals have toxins located in their skin, musculature, viscera or body fluids. They do not possess an apparatus with which to inject these toxins, and the toxins can only enter via the gastrointestinal tract following consumption of the poisonous animal. These animals are chiefly marine creatures, in particular fish and shellfish. Microbial food poisoning, e.g. botulism, is not covered in this guide, as this is caused by toxic substances that may develop due to incorrect preservation of food, and is not specific to animal foodstuffs.
- Poisonous animals: Diagnosis & Treatment, Biomedical database
PARENTERAL INTOXICATION caused by an external injury (puncture wound, bite, sting or a similar injury) by a venomous animal
Venomous animals, see below under point 2.
2. Accidents caused by VENOMOUS animals |
WHERE did the accident occur?
- In the water or on the water's edge: see below under point 3.
- On land: see below under point 4.
3. Accidents caused by WATER-DWELLING venomous animals |
In the case of accidents caused by animals in FRESHWATER, there are the following possibilities:
- Painful puncture wounds from fish
Diagnosis & Treatment
Biomedical database
For more precise identification of the relevant animal, see Table 3.1
- Painful wounds caused by platypuses (only eastern regions of mainland Australia and Tasmania)
Biomedical database
- Barely noticeable bites from sea snakes (in river mouths and further upstream in the Indo-Pacific region as well as in Lake Taal on Luzon, in the Philippines, and Lake Tegano on Rennell Island, in the Solomon Islands)
Diagnosis & Treatment
Biomedical database
For more precise identification of the relevant animal, see Table 3.1
N.B. Terrestrial venomous snakes are sometimes found in freshwater. However, only rarely do bites occur in the water.
For accidents occurring in the MARINE ENVIRONMENT (seawater, brackish water and adjacent shore regions), the following two forms of venom application can be distinguished:
-
Venom application to an area of skin caused by animals that have a number of microscopically small venom apparatuses distributed over their body surface or in the tissue. Following contact there are usually visible and painful changes to the affected area of skin, in the form of blotches, welts, abrasions and the like.
Possible causes are: sponges, cnidarians, sea cucumbers and bristle worms. For more precise identification of the relevant animal, see Table 3.1. - Localised/punctate venom application by teeth, spines and the like. The consequent bite or puncture wounds can sometimes be barely noticeable or visible! Possible causes are: sea snakes, cone shells, the blue-ringed octopus, bristle worms, sea urchins, starfish or venomous fish. For more precise identification of the relevant animal, see Table 3.1.
4. Accidents caused by TERRESTRIAL venomous animals |
In order to identify the cause of an accident on land, the minimum requirement is that the patient saw the animal in question. If this was not the case, identification is difficult. Considering the large number of different types of venomous animals, bite or puncture marks are not sufficiently specific as a basis on which to make a satisfactory classification. However, some venomous animals can be excluded on the basis of geographical or clinical criteria or the circumstances of envenoming.
A rough description of the animal by the patient should be sufficient to distinguish between the two main animal categories in which medically relevant venomous animals occur.
Arthropods
They possess a more or less hard-shelled external skeleton of chitin, 3 or more pairs of legs and a segmented body with or without wings.
Venomous members of this group are scorpions, spiders, centipedes and some insects and ticks.
For more precise identification of the relevant animal, see Table 3.2 and Table 3.3.
Reptiles
As vertebrates they do have a spine. The skin is covered with horny scales.
Possible causes are:
- Snakes. In contrast to other limbless reptiles they have no eyelids.
- Terrestrial snakes
- Diagnosis & Treatment
North America
Mexico and Central America
South America and the West Indies
Europe
North Africa, Near and Middle East
Central and Southern Africa
The Far East
Indian Subcontinent and Southeast Asia
Australia and the Pacific Islands - Morphological identification key
- Distribution tables (choose region or animal)
- Biological tables (chose region)
- Biomedical database (choose snake family)
- Diagnosis & Treatment
- Terrestrial snakes
- Heloderma spp. (Beaded lizard and Gila monster). Sturdy body, 2 pairs of legs. Only occur in the southwest of the USA, in western Mexico and in Central America.
Table 3.1 More precise identification of the cause in accidents with venomous animals in water
| Distribution | Characteristics | Venom effects |
Biomedical database Diagnosis & Treatment |
|||
| Fresh water |
Marine environment |
|||||
| Injury due to extensive contact/abrasion | ||||||
|
Hard consistency
Stony corals |
|
tropical and subtropical reef areas |
sessile; often extend over large areas; stable calcium carbonate skeleton; highly variable growth forms, from flat to highly branched |
generally only local | ||
|
Spongious/elastic consistency
|
medically significant species in the coastal waters of the Caribbean and the Pacific |
sessile, solitary or in colonies; variable growth forms, flat, barrel-, pipe- and cup-shaped forms; porous surface |
generally only local | Biomedical database | ||
| Feather hydroids |
|
tropical to cool coastal zones |
sessile; feather-like form; flexible, chitin-like supporting skeleton |
generally only local | ||
|
Soft or gelatinous consistency
|
|
tropical to cold seas and oceans |
free-swimming, in areas close to the coast or in the open sea; no supporting skeleton; many colourless, transparent species; consist of a bell and attached tentacles that may be up to several meters in length |
often only local effects, but some species cause severe systemic effects | ||
| Anemones |
tropical to cold coastal areas; often in the intertidal zone |
flower-like animals with no supporting skeleton; consist of a sessile pedal disk (foot) with a crown of tentacles on top |
generally only local | |||
|
Marine worms
|
|
tropical to warm oceans |
elongated, segmented body; fine bristles along the sides of the body; largest specimens 1–3 m | generally only local | Biomedical database | |
| Injury due to puncture wound/bite | ||||||
|
Barely noticeable wounds/bites
Cone shells |
|
primarily tropical coastal areas of the Indian and Pacific Oceans |
marine snails with shells in the form of a rolled cone; shells often have striking patterns; largest species up to 15 cm; can be dangerous if handled (they are sought after by collectors); sting barely noticeable |
hardly any local effects; can be severe systemic effects |
Biomedical database | |
|
Octopuses, Blue-ringed octopus |
generally in tropical to cold seas and oceans; Blue-ringed octopus in coastal waters of Australia |
typical octopus form with a "head" and 8 arms; brownish colour with luminous blue rings |
Blue-ringed octopus: hardly any local effects, but severe systemic effects; other species: generally only local |
Biomedical database | ||
| Sea snakes |
river mouths and further upstream; Indo-Pacific region; in Lake Taal, Philippines, and Lake Tegano, Solomon Islands |
coastal waters of the Indo-Pacific, from the Persian Gulf eastwards to Japan and southwards to Australia; one species in the open sea as well as on the east coast of Africa and the west coast of Central America |
differ from snake-like fishes in that they have no fins or gills; in contrast to terrestrial snakes they have a laterally flattened tail; most common in the shallow coastal waters of Southeast Asia, New Guinea and Australia; bite marks often barely visible |
hardly any local effects, but severe systemic effects |
||
|
Painful puncture wounds
Numerous small injuries
Sea urchins and starfish |
venomous sea urchins in tropical and warm zones of the Indian, Pacific and Atlantic Oceans; Crown-of-thorns starfish in coral reefs of the Indo-Pacific |
bottom-dwelling; venomous sea urchins among both long- and short-spined species; following injuries with long-spined species broken-off spine tips may remain under the skin; Crown-of-thorns starfish covered in massive spines; animals have a diameter of up to 40 cm; large puncture wounds |
generally only local, but sometimes also systemic effects |
|||
|
Single puncture wounds
|
Catfishes throughout the world in rivers and lakes
stingrays in rivers in South America |
tropical to cold seas and oceans; greatest variety of dangerous species in tropical coastal waters |
many bottom-dwelling species, which sometimes bury themselves or hide in crevices and often have camouflage colouring; some species also in the intertidal zone; accidents occur not only in the water, but also while fishing or preparing the fish |
often only local effects, but some species also cause systemic effects |
||
Table 3.2 More precise identification of the cause in accidents with venomous arthropods1 on the basis of the circumstances
Beetles, Biomedical database
1 Stings from blood-sucking insects, in particular mosquitoes, flies and horseflies, can also cause local or allergic reactions.
Signs of paralysis due to attached ticks2?
yes
Ticks, Biomedical database
no
Local or systemic envenoming due to a sting/bite?
yes
Scorpions
Spiders
Bees, wasps or ants
Centipedes
for more precise identification see Table 3.3
no
Local reactions due to a venomous secretion on the skin?
yes
Millipedes, Biomedical database
no
Tiny urticating hairs that penetrate the skin after contact or enter the airways or eyes from the air and lead to inflammatory reactions. Rarely also systemic effects.
Butterflies or their caterpillars, Biomedical database
Bird spiders, Biomedical database
2 Ticks may already have fallen off when the signs of paralysis are observed.
Table 3.3 Identification of the cause in accidents with terrestrial arthropods
| Distribution | Biological characteristics | Circumstances of envenoming |
Risk | Incidence | |
|
Scorpions |
throughout the world from tropical to temperate zones; dangerous species in the southwest of the USA, Mexico, |
the head and body are fused, the tail is markedly narrower, body segmented; 4 pairs of legs, 1 pair of large pincers on the head; tail consists of 5 segments and the venomous sting; live hidden on the ground or in vegetation or under bark; also found in loose brickwork and often in human habitations; nocturnal |
stings painful, usually on the feet or hands, while walking barefoot and during careless handling of the animals; accidents occur outdoors as well as indoors, where scorpions like to search out damp places or crawl between the sheets or in clothes lying around or inside shoes |
stings from some species are potentially life-threatening; venom effects: predominantly neurological effects |
in Mexico, Trinidad, Brazil, North Africa, the Middle East and India they are a common cause of serious accidents with venomous/poisonous animals |
|
Spiders |
throughout the world; dangerous species chiefly in tropical and warm regions |
the head and thorax form a single unit (cephalothorax), to which 4 pairs of legs are attached, 2 venomous fangs in the mouth region; the abdomen is separated from the cephalothorax by a narrow "waist" (pedicel); no further body segmentation; |
bites from dangerous species usually painful, although sometimes barely noticeable; accidents occur outdoors and indoors; some Bird spiders have urticating hairs that can be thrown off and can lead to irritation of the mucous membranes and the eyes |
envenoming caused by some species can take a severe systemic course or lead to local necrosis; venom effects: predominantly local or neurological effects |
envenoming caused by dangerous species is less common than scorpion bites or bee or wasp stings |
|
Ticks |
envenoming most commonly known to occur in North America and Australia; |
small head fused with the body; body not divided or segmented; 4 pairs of legs; as ectoparasites they bite humans and attach themselves firmly while sucking blood for a long period; during this time the abdomen swells enormously |
envenoming is caused by toxic substances in the saliva, but only in certain populations of ticks; it is barely noticeable when they bite and attach; symptoms progress over several days |
severe neurotoxic envenoming with ascending paralysis possible |
envenoming rare |
|
Hymenopterans (Bees, Wasps and Ants) |
throughout the world from tropical to cold climates |
body divided into head, thorax and abdomen, last two segmented; 3 pairs of legs and 2 pairs of transparent, membranous wings on the thorax; wings only rarely seen in ants; venomous sting on the posterior section of the abdomen; diurnal; form colonies |
painful stings; multiple stings possible, particularly close to the nest |
with single stings local effects; however, allergic persons may suffer autopharmacological effects and possibly anaphylactic shock; with multiple stings (several hundred or thousand) severe envenoming with haematological effects possible |
hymenoptera stings are the most common cause of accidents with venomous/ poisonous animals altogether; allergic reactions are common; severe envenoming due to multiple stings is rare |
|
Lepidopterans (Butterflies and Caterpillars) |
severe intoxication due to butterflies in particular in the tropical Americas; caterpillars with urticating hairs found worldwide; most dangerous species in the tropics of South America |
elongated body divided into a head, thorax and abdomen; 3 pairs of legs and 2 pairs of large wings that are covered in tiny scales; in species that can cause envenoming, the body and wings are thickly covered with urticating hairs; caterpillars of many species are also covered with clearly discernible urticating hairs |
envenoming caused by contact or inhalation; as a consequence of mass occurrences of medically relevant species the air is filled with urticating hairs |
primarily local effects; rarely also systemic effects with renal failure |
epidemic outbreaks in particular regions |
|
Coleopterans (Beetles) |
throughout the world; in particular in arid and semi-arid zones |
as with all insects the body is divided into three (head, thorax, abdomen) with 3 pairs of legs; 2 pairs of wings, although the forewings are usually in the form of hard shield-like protective wings
|
envenoming caused by secreted body fluids (not perceptible initially) or after crushing these beetles on the skin; causes erythema and blistering; if the venom enters the eye, conjunctivitis |
generally only local effects |
? |
|
Centipedes |
larger dangerous species primarily in tropical Asia |
elongated, uniformly segmented body; body dorsoventrally oblate; some species up to 20 cm or longer; each body segment carries a pair of legs (except the last two); depending on the species, 15 to far more than 100 pairs of legs; 2 powerful venom claws in the head region; nocturnal, during the day they hide under stones, wood and the like |
painful bites by means of the powerful venom claws |
local effects; in rare cases neurological effects also possible |
envenoming rare |