Cone Shell Mollusc Poisoning

 Non-Fatal Case Studies
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He was diving in Nanakuli seeking shells in the sand bottom. Noticing a shell half buried in the sand he picked it up, when almost immediately the cone stung him on his middle finger. Despite sucking the wound to draw out any poison, within fifteen minutes he developed a bad headach. During the next twelve hours at home he was extremely nauseated, followed by painful stomach cramps through the night. He stated that shortly after the initial sting he experienced a noticeable shortness of breath, almost, as he described it, as if someone was sitting on his chest. By the next morning these symptoms had ceased but the wounded finger continued to pain him. 
     Considering that this particular Conus textile was a very small member of its species, the potency and peril represented by a larger specimen can easily be envisaged. 
     The only other Conus sting incident I was aware of during my stay in Hawaii involved a shell collector who was not a member of our immediate group. He stated that he had just returned to the beach after collecting several shells, among them a Conus halitropus, now known as Conus obscurus. The shell is oval in outline and very light in weight. The outer lip is very thin, flaring, and encloses a wide aperture. The color is a yellowish-brown that is marked by irregular flesh colored areas. It reaches a  maximum length of about 1 3/4 inches. For lack of a better place to put the cone he placed it on his head beneath a navy watch cap. A short time later he felt a mild stinging sensation. He reported that very shortly the top of his skull became significantly numb, a felling that persisted for several hours afterwards. This incident came as quite a surprise to us, because we had been handling Conu halitropus with impunity never realizing that it possessed a stinging potential that could even mildly affect a human. Sometimes pure luck follows the ignorant!
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Hawaiian Malacological Society Shell News, 08/01/56 


 


Envenomation by a Conus geographus

"Right near the end of an early-afternoon dive, C. rolled a coral boulder just before he started his ascent from about 60 ft. Under the boulder, sure enough, was a cone, about 90 mm, that he recognized as a smallish geographus. He picked it up and put it in his thick mesh collecting bag, one of the tough ones with very tight mesh, that you'd think nothing could sting through. He then clipped it onto the diving harness on his chest, and started his ascent. On the way up, he felt a sting on his chest, which he first thought was a jellyfish. He looked down, and saw that the sting came from where the bag was, so he looked down at the bag to see if it could have been the cone. Sure enough, the geographus had crawled up toward the top of the bag (which was velcro-ed shut). He realized he had been stung through the bag, through a T-shirt, by this very active cone." 

"When I saw him yesterday evening about 6:00 he still felt fine, but had obviously been shaken by the sting. It didn't look too bad, about like a bee sting. On the drive home, however, he started feeling sick, and was quite sick during the night. Even today he was not feeling so great, and was still really weak. The good news is he survived a sting by a very venomous cone.  That brought a lot of questions to mind. Does the depth of the sting have a lot to do with how much envenomation occurs? It seems like it might. Does the fact that it was a small animal mean it was less dangerous? Are the radular teeth larger on a large cone? Significantly larger? Is the venom evenly distributed along the tooth, or is it more concentrated at the tip or base? Which cones are known to use their "harpoons" in self-defense, rather than in hunting food? Does a cone really have to be aggravated or provoked to cause such a reaction, or will some of them do it readily?  I've collected quite a few live cones, and I'm always careful with them even if they are not thought to be terribly venomous. This incident makes me doubt whether my thin gloves are really any protection against a cone intent on stinging something. Even five hours after he was captured, this little fellow was extremely active, crawling across the cement driveway, "feeling" for something to sting. I've never seen any other cone behave so aggressively. As I mentioned earlier, it was small for a geographus, about 90 mm, and quite red in color. It almost looked somewhere in between a Conus obscurus and geographus (at least the color made me think of obscurus), heavily coronated, with a flattish spire (definitely more like geographus than obscurus)."
By Don Barclay, CONH-L Mailing List, 04/22/97, Pago Pago 


 

 Fatal Case Study
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C.H.G. , a male, aged twenty-seven years, whilst on a pleasure cruise landed at Haymen Island on June 27, 1935, and picked up a live cone shell (since identified by Mr. H.A. Longman, of the Queensland Museum, as Conus geographus). According to an eye-witness, it was gripped in the palm of one hand, with the open side downwards in contact with the skin, whilst with the other he proceeded to scrape with a knife, the epidermis, that is, a thin cuticle covering the hard part of the shell. It was during this operation that he was stung in the palm of the hand. "Just a small puncture mark  was visible, Dr. Clouston did not see the patient until just before death, but the following details were obtained by him from the patient's mother, who was present with him. Local symptoms of slight numbness started almost at once. There was no pain at any time. Ten minutes afterwards there was a feeling of stiffness about the lips. At twenty minutes the sight became blurred with diplopia; at thirty minutes the legs were paralysed; and at sixty minutes unconsciousness appeared and deepened into coma. No effect was noted upon the skin, lymphatic, alimentary or genito-urinary systems. Just before death, the pulse became weak and rapid, with slow, shallow respirations. Death took place five hours after the patient was stung. Post mortem examination showed that all the organs, heart, lungs et cetera, were quite healthy. Mr. J.B. Henderson, Government Analyst, reports that no poison was found in the stomach contents. The victim was prior to the injury in perfect physical condition and in training for football. The symptoms resemble much those of •curare• poisoning as described in earlier reports...
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By H. Flecker, The Medical Journal of Australia, 04/04/36, p. 264/6 
 
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