Assessing the Efficacy of First-Aid Measures in Physalia sp. Envenomation, Using Solution- and Blood Agarose-Based Models

Abstract

Stings from the hydrozoan species in the genus Physalia cause intense, immediate skin pain and elicit serious systemic effects. There has been much scientific debate about the most appropriate first aid for these stings, particularly with regard to whether vinegar use is appropriate (most current recommendations recommend against vinegar). We found that only a small percentage (≤1.0%) of tentacle cnidae discharge during a sting event using an ex vivo tissue model which elicits spontaneous stinging from live cnidarian tentacles. We then tested a variety of rinse solutions on both Atlantic and Pacific Physalia species to determine if they elicit cnidae discharge, further investigating any that did not cause immediate significant discharge to determine if they are able to inhibit cnidae discharge in response to chemical and physical stimuli. We found commercially available vinegars, as well as the recently developed Sting No More® Spray, were the most effective rinse solutions, as they irreversibly inhibited cnidae discharge. However, even slight dilution of vinegar reduced its protective effects. Alcohols and folk remedies, such as urine, baking soda and shaving cream, caused varying amounts of immediate cnidae discharge and failed to inhibit further discharge, and thus likely worsen stings.

Evaluation of Cyanea capillata Sting Management Protocols Using Ex Vivo and In Vitro Envenomation Models

“…This may reflect individual animal variability in potency or differences in the duration of time between animal capture at sea and the removal of tentacles for the experiments. Nonetheless, the observed reduction of venom activity by heat ( Figure 5 ) is in concurrence with similar studies in hydrozoans [ 42 ] and cubozoans [ 22 , 36 ] and the body of clinical literature that demonstrates improved clinical outcomes with heat application as well as the low level of heat thermotolerance of cnidarian venoms (for a review see [ 43 ]). Some have suggested that improved outcomes from heat application (in particular the reduction of pain seen in clinical studies [ 44 , 45 , 46 ]) are not the result of reduction in venom activity, but instead, reflect modulation of neurological pain processing [ 47 ].…”

“…Because of the great diversity of stinging jellyfish (cubozoans, hydrozoans and scyphomedusae), it has been previously stated that different jellyfish may require different treatments [ 9 , 65 ]. Building on previous work on box jellyfish [ 22 , 43 ] and the Portuguese man o’ war [ 42 ], this study now shows that jellyfish from three different classes of Cnidaria (Cubozoa, Hydrozoa and Scyphozoa) respond in the same way to the application of vinegar (despite slight differences in response to vinegar in vitro) and heat. This will therefore, simplify the development of a first aid protocol for jellyfish stings even in countries that have several very different venomous jellyfish species.…”

“…Urine, a commonly believed folk remedy for jellyfish stings, was even worse than seawater ( Figure 4 ), which aligns with out TSA data showing it elicits ~50% discharge of all cnidae types. These results stress the importance of evaluating first aid protocols using functional activity assays rather than solution-only tests, as they add to a growing number of studies that have shown in vitro examinations are not necessarily predictive of clinically relevant effects [ 22 , 23 , 42 ].…”

Stress-Induced Mucus Secretion and Its Composition by a Combination of Proteomics and Metabolomics of the Jellyfish Aurelia coerulea

“…Blooming jellyfish consume fish eggs, crush captured fish, clog or destroy fish nets and block power-plant intakes, leading to disruption of marine ecosystems and thereby causing significant economic losses. Moreover, with massive increases of jellyfish blooms in recent years in coastal areas, the number of victims stung by jellyfish, including swimmers, fishermen and divers, has consequently increased [ 2 , 3 ]. Contact with jellyfish tentacles can trigger millions of nematocysts to pierce the skin and inject venom, causing responses ranging from no effect or local pain, to a series of severe systemic manifestations such as cardiovascular collapse, liver dysfunction, renal failure, and even death [ 4 , 5 , 6 ].…”

First envenomation report of the Cnidarian Physalia physalis in Indonesia

“…Therefore, the trained beach lifeguards also used traditional treatments such as tobacco, toothpaste, salt, ethyl chloride, and even urinated at the stung skin they believe are as effective as the first aid. Though those treatments are not scientifically proved [22].…”