What are the symptoms of a jellyfish sting? How do you diagnose and treat a jellyfish sting? Get the facts about jellyfish stings, including the types of jellyfish, risk factors, and prevention tips.

Understanding Jellyfish Stings

Jellyfish stings are a fairly common occurrence for people swimming, wading, or diving in oceans. These stings happen when the long tentacles of a jellyfish come into contact with the skin, injecting venom from thousands of microscopic barbed stingers. Most jellyfish stings cause immediate pain and inflamed marks on the skin, but some can lead to more severe, whole-body (systemic) reactions, and in rare cases, even be life-threatening.

Symptoms of Jellyfish Stings

The symptoms of a jellyfish sting can vary in severity, but typically include:

• Burning, prickling, or stinging pain
• Welts or tracks on the skin, showing the pattern of the tentacles
• Itchiness (pruritus)
• Swelling
• Throbbing pain that radiates up a leg or arm

More severe reactions can affect multiple body systems and may include:

• Stomach pain, nausea, and vomiting
• Headache
• Muscle pain or spasms
• Faintness, dizziness, or confusion
• Difficulty breathing
• Heart problems

Factors Affecting Sting Severity

The severity of a jellyfish sting can depend on several factors, including:

• The type and size of the jellyfish
• The age, size, and health of the person affected (severe reactions are more likely in children)
• How long the person was exposed to the stingers
• How much of the skin was affected

When to Seek Medical Attention

If you experience severe symptoms, such as difficulty breathing, seek emergency medical treatment immediately. Additionally, see a healthcare provider if your symptoms worsen or the wound shows signs of infection.

Causes of Jellyfish Stings

Jellyfish stings are caused by brushing against a jellyfish tentacle. These tentacles have thousands of microscopic barbed stingers, each with a tiny bulb that holds venom and a coiled, sharp-tipped tube. When the skin comes into contact with the tentacle, the triggers on the surface release the stingers, which pierce the skin and inject the venom.

Common Types of Jellyfish

While many types of jellyfish are relatively harmless to humans, some can cause severe pain and systemic reactions. These include:

• Box jellyfish: Can cause intense pain and, rarely, life-threatening reactions. Found in warm waters of the Pacific and Indian oceans.
• Portuguese man-of-war (bluebottle jellyfish): Have a blue or purplish gas-filled bubble that keeps them afloat, mostly found in warmer seas.
• Sea nettle: Common in both warm and cool seawaters.
• Lion’s mane jellyfish: The world’s largest jellyfish, with a body diameter of more than 3 feet, found in cooler, northern regions of the Pacific and Atlantic oceans.

Preventing Jellyfish Stings

To help avoid jellyfish stings, consider the following tips:

• Wear a protective suit, such as a wetsuit or “stinger suit,” when swimming or diving in areas where jellyfish stings are possible.
• Get information about local conditions from lifeguards, residents, or health officials before entering the water, especially in areas known to have high jellyfish populations.
• Avoid swimming or wading in the water during jellyfish season, when their numbers tend to be higher.

Diagnosis and Treatment

Diagnosing a jellyfish sting typically doesn’t require a visit to a healthcare provider, as the injury can usually be identified by its appearance. However, a provider may collect samples of the stingers to help guide treatment.

First-aid care for a jellyfish sting includes carefully removing any visible tentacles with tweezers and soaking the affected skin in hot water (110-113°F/43-45°C) until the pain subsides, which can take 20-45 minutes. For severe reactions, medical treatment may be necessary.

In summary, jellyfish stings are a common ocean-related injury that can range from mildly irritating to potentially life-threatening, depending on the type of jellyfish and other factors. By understanding the symptoms, causes, and prevention methods, individuals can take steps to avoid these stings and seek appropriate medical care if necessary.