Human contact with venomous marine creatures is common and may result in serious harm from biological toxins or mechanical injury inflicted by the stinging apparatus. Significant morbidity results from envenomation by spiny fish, cone snails, octopi, sea snakes, and several species of jellyfish. Despite advances in basic science research regarding the biochemical nature of marine toxins and their mechanisms of action, our knowledge of the pathophysiology related to clinical syndromes in humans and the optimal therapies for human envenomation remain limited. Evidence for effective treatment is primarily derived from in vitro and in vivo animal research without the benefit of controlled human trials. However, current research in toxinology coupled with clinical observations allows the development of cogent treatment guidelines for victims of marine envenomation.
The phylum Cnidaria (formerly Coelenterata) includes more than 9000 species, of which approximately 100 are known to injure humans. They are commonly referred to as jellyfish; however, their phylogenetic designations separate “true jellyfish” and other organisms into distinct classes (Table 119–1; Fig. 119–1A). All species possess microscopic cnidae (the Greek knide means nettle), which are highly specialized organelles consisting of an encapsulated hollow barbed thread bathed in venom. Thousands of these stinging organelles, called nematocysts (or cnidoblasts), are distributed along tentacles. A trigger mechanism called a cnidocil regulates nematocyst discharge. Pressure from contact with a victim’s skin, or chemical triggers such as osmotic change, stimulates discharge of the thread and toxin from its casing. Penetration of flesh leads to intradermal venom delivery. Nematocysts of most Cnidaria are incapable of penetrating human skin, rendering them harmless. Cnidaria causing human envenomation, such as the box jellyfish, discharge threads capable of penetrating into the papillary dermis.136
TABLE 119–1.Characteristics of Common Cnidaria |Favorite Table|Download (.pdf) TABLE 119–1. Characteristics of Common Cnidaria
|Latin Name ||Common Name ||Habitata |
|Cubozoa class || || |
| Chironex fleckerib ||Box jellyfish ||Tropical Pacific Ocean, Indian Ocean, Gulf of Oman |
| Carukia barnesib ||Irukandji jellyfish ||North Australian coast |
| Chiropsalmus sppb ||Sea wasp or fire medusa ||North Australian coast, Philippines, Japan, Indian Ocean, Gulf of Mexico, Caribbean |
| C. quadrigatus || || |
| C. quadrumanus || || |
| Carybdea alata ||Hawaiian box jelly fish ||Hawaii |
| Carybdea rastoni ||Jimble ||Australia |
|Hydrozoa class || || |
| Physalia physalisb ||Portuguese man-of-war ||Eastern US Coast from Florida to North Carolina, Gulf of Mexico, Australian coastal waters (rare reports) |
| Physalia utriculus ||Bluebottle ||Tropical Pacific Ocean, particularly Australia |
| Millepora alcicornis ||Fire coral ||Widespread in tropical waters, including Caribbean |
|Scyphozoa class || || |
| Chrysaora quinquecirrha ||Sea nettle ||Chesapeake Bay, widely distributed in temperate and tropical waters |
| Stomolophus meleagris ||Cabbage head or cannonball jelly fish ||Gulf of Mexico, Caribbean |
| Stomolophus nomuraib || ||Yellow Sea between China and South Korea |
| Cyanea capillata ||Lion’s mane or hair jelly fish ||Northwest US coast up to Arctic Sea, ...|
Pop-up div Successfully Displayed
This div only appears when the trigger link is hovered over.
Otherwise it is hidden from view.