On 12th September 2015, a 31-year-old Chinese man was stung by a jellyfish while he was enjoying his vacations at Chaweng beach, Samui island. Soon after he lost consciousness. He was doused with vinegar & cardiopulmonary resuscitation was started at the hospital approximately 10 to 15 min after being stung. He was then shifted to the Intensive Care Unit and put on a respirator.



The case in discussion here is of a box jellyfish sting, a highly dangerous jellyfish responsible for fatalities on the islands of Samui and Pha-ngan in the Gulf of Thailand. Though box jellyfish sting cases are rare but life-threatening. From 1997 to 2015, 15 such cases have been reported on these islands, highest incidence during the month of August, a majority by Chironex fleckeri, a species of box jellyfish.

Source: https://www.instagram.com/p/B6OobvXhATT/

Box Jellyfish

Box jellyfish has a cube-shaped body with long tentacles, reaching up to 10 feet in length. It has a well developed nervous system enabling its rapid movement and fast swimming, up to 2 meters per second. With its 24 eyes, it can adapt to light and dark environment.



Symptoms

Chironex fleckeri, the most lethal member of Chirodropidae family has a powerful venom that can cause cardiopulmonary depression soon after the sting due to its ability to degrade cell walls. This results in a leak of potassium, leading to hyperkalemia. Death can occur within minutes after being stung. Other symptoms reported by victims include

Severe burning pain

Numbness

Oedema

Itching

Shortness of breath

Unconsciousness

Difficulty swallowing and speaking

Shivering

Fever

Irregular pulse/heart failure

Box jellyfish is transparent, disappearing in the clear waters, therefore till the time victim realises, the venom has already spread. Caterpillar tracks or ladder-like burn marks appear on the skin of the victim.



A sting victim’s leg after a Sting in the North of Koh Samui (2012) Source: https://www.thethailandlife.com/box-jellyfish-thailand

First Aid



The stinging cells on the tentacles are triggered by the chemicals of the skin, not by touch. After adhering to skin, it pumps venom, causing intense agonizing pain.

Wash with vinegar for 30-60s (it deactivates nematocysts to suppress venom release). Remove the attached tentacles (Use a towel or gloved hand to remove tentacles to prevent secondary stinging, causing further envenomation.) Immerse in hot water Immobilize the affected area and maintain at a gravity-neutral level. Call out for emergency attention. Apply anti-venom if available.

Some evidence advise against the use of vinegar as it has shown to exaggerate the envenomation. Moderate pain can be alleviated with hot packs.

For swelling and itching, mild hydrocortisone cream or an oral antihistamine can be given. Antibiotics might be necessary if the patient develops cellulitis.

Prevention

Avoid night swimming

Avoid beaches or waters with a known jellyfish infestation, especially during peak seasons

Wear protective swim gear

Avoid picking up dead jellyfish

If a regular swimmer of fresh-water, beware of the first aid steps.

Avoid touching marine animals while snorkelling

Food for thought

Shouldn’t proper instructions and clear warnings be put up on the notorious beaches?

References



Thaikruea, Lakkana & Siriariyaporn, Potjaman. (2016). The magnitude of severe box jellyfish cases on Koh Samui and Koh Pha-ngan in the Gulf of Thailand. BMC Research Notes. 9. 108. 10.1186/s13104-016-1931-8.



Barbara J. Drobina, D. (n.d.). Jellyfish Stings Reaction, Symptoms, Pictures, and Treat. Retrieved from Emedicine Health: https://www.emedicinehealth.com/jellyfish_stings/article_em.htm#jellyfish_sting_definition_and_facts