homologous against the same coelenterate antigen and heterologous against antigens contained within
vaccinia and herpes simplex viruses and tetanus bacillus.
Clinical aspects. The clinical presentation of a sea nettle envenomation is similar to that of Physalia
species, with perhaps a greater incidence of systemic complications. Death is exceedingly rare. Elevated
levels of serum anti sea nettle venom IgM, IgG, and IgE may persist for years in victims who suffer
exaggerated reactions to Chrysaora quinquecirrha stings. These antibodies cross-react with Physalia venom
and have been postulated to be of value in identifying patients at risk for a severe reaction. Currently this
technique is not widely available or frequently employed, and its reliability and reproducibility require further
verification.
The reaction after a sting by the blubber jellyfish (Catostylus species) is relatively mild, with the
formation of wheals, erythema, and pruritus limited to the areas of contact. Systemic effects are exceedingly
rare. Cyanea species carry long thin tentacles that induce a similar effect, with occasional muscle aching,
nausea, and drowsiness, particularly in small children. Pelagia species also induce wheals, which are more
circinate or irregularly shaped and may not follow a linear pattern. The venom is sufficiently toxic to cause
severe generalized allergy, with bronchospasm and pruritus.
Treatment. Treatment for a sea nettle envenomation is similar to that for the sting of Physalia species.
Baking soda may be the most effective commonly available initial detoxicant.35 Monoclonal antibodies to
jellyfish venoms have been developed that demonstrate cross-reactivity among venoms of a variety of
coelenterates, which may allow the development of a single protective antivenom or vaccine.
Anthozoa
The class Anthozoa includes the sea anemones, stony (true) corals (Zooantharia), and the soft corals
(Alcyonaria). The anemones are considered here because they envenom.
Actinaria (Anemones). Actinarians (sea anemones) are abundant (1000 species) multicolored animals
with sessile habits and a flowerlike appearance. They are composed of stalked, fingerlike projections capable
of stinging and paralyzing passing fish. Their sizes range from a few millimeters to more than 0.5 m; they are
found at depths of up to 2900 fathoms. The insides of some anemones can be eaten after they are dried.
Anemones can be colorful creatures and found in tidal pools, where the unwary brush up against them
or inquisitively touch them. Other anemones burrow bottom mud or sand. Like other coelenterates, they
possess tentacles loaded with one of two variations of the nematocyst, either the sporocyst or the basitrichous
isorhiza (basitrich). These wreak havoc once stimulated by an unfortunate victim. Some sporocysts are
adhesive and act to hold as well as to envenom the prey. When an exposed anemone wishes to present a
greater number of nematocysts to the victim, it inflates the tentacles by filling them with water. Many
anemones also secrete mucous, which covers the anemone's body and may contain cytolytic and hemolytic
protein toxins. These may serve to repel potential predators.
While a number of sea animals, such as the clownfish (anemonefish) of the genera Amphiprion and Premnas,
live in symbiosis with certain anemones (Heteractis spp., Stichodactyla spp., Macrodactyla doreensis,
Entacmaea quadricolor, and Cryptodendrum adhaesivum), humans are not so fortunate and are frequently
stung when attempting to handle these not so delicate "flowers." The clownfishes have evolved resistance to
the anemone's sting by repeated contact and development of a mucous coat, and perhaps by immunity.
Sea anemones contain biologically active substances, including neurotoxins (sodium channel interaction),
cardiotoxins, hemolysins (for erythrocytes and platelets), and proteinase inhibitors. A cytolytic toxin has been
isolated from the Indo-Pacific sea anemone Stoichactis kenti. The anemone Actinia equina elaborates
cytolytic polypeptide toxins known as equinatoxins, which may induce hemolysis as well as cardiorespiratory
arrest in animals, attributed by some to coronary vasospasm. Tenebrosin-C from the anemone Actinia
tenebrosa is a positive inotrope that can be inhibited by the cyclooxygenase blockers indomethacin and
aspirin, a lipooxygenase blocker and leukotriene antagonist, and mepacrine (a phospholipase A
2
inhibitor).
Potassium channel toxins have been isolated from the sea anemones Bundosoma granulifera and
Stichodactyla helianthus. Cytolytic toxins elaborated by anemones include "cytolysins," which are felt to
exert their effect by damaging membranes via pore or channel formation.
Clinical aspects. Most victims are stung when they handle or accidentally brush against an anemone in
shallow water. Nudists may acquire genital injuries; small children may accidentally or intentionally ingest
tentacles. The dermatitis caused by contact with an anemone is similar in all regards to that from fire coral or
