Generally, there are more than a thousand jellyfish species worldwide. While most jellyfish stings do not cause any health problems or symptoms, some of them may cause serious problems. These creatures live in all of the world’s oceans, and they have soft, bell-shaped bodies with certain long and finger-like structures (tentacles). They also have stinging cells (known as nematocytes) that are located inside their tentacles. In some cases, a jellyfish may contain thousands of these nematocytes in one tentacle. Thus, these stinging cells may contain venom (a poisonous substance) that helps them protect themselves. It also helps them get food by stinging it. Most of the time, jellyfish do not sting humans, but may sting them when a person brushes up against them while he/she swims. If you experience breathing problems or other serious symptoms, immediately call 911 or go to the nearest emergency room (ER).
Generally, jellyfish stings are common, and there are about 150 million stings worldwide each year.
Types of Jellyfish
While most jellyfish stings are harmless, some types may cause serious health problems. Check some examples below:
- Box – This is one of the most deadly jellyfish in the world. In some cases, they are known under the name of sea wasps, and they have box-like bodies with tentacles that extend from each corner. Usually, they live in tropical areas around the world, but are mostly found on the northern coast of Australia and the Indo-Pacific Ocean. In general, there are about 40 types of box jellyfish. Those that live in Australia are considered the most venomous jellyfish.
- Lion’s mane – This is the largest jellyfish in the world, and it may grow up to 3 feet wide, but the tentacles may reach 120 feet long. They often live in the cooler climates in the Arctic and the North Pacific Ocean. The name of this jellyfish comes from the hundreds of stinging-covered tentacles that make up their mane.
- Sea nettle – This type of jellyfish is one of the most common found along the Pacific, Atlantic, and Gulf coasts. They can grow more than 1 foot wide and often have 24 tentacles that may reach 6 feet long.
- Portuguese man-of-war – While it is not a jellyfish technically, it looks very similar. They often live in the tropical waters of the Pacific, Indian, and Atlantic oceans and the Caribbean Sea. Furthermore, this creature is rarely fatal to humans, but may cause severe symptoms because of its long strands of tentacles and polyps that may grow up to 30 feet long.
How Does a Jellyfish Sting Affect My Body?
Typically, people react differently to jellyfish stings because it depends on several variables. While some jellyfish stings cause mild irritation, others can be fatal. Check some factors below:
- Type of jellyfish
- Where on the body you were stung
- The surface of the exposed skin
- How long the venom has been in the body
- Your age, body weight, and overall health
What Are The Symptoms of a Jellyfish Sting?
While a jellyfish sting may not cause severe symptoms (such as pain, itching, and irritation), you should seek immediate medical attention if any of the following symptoms occur. They often happen when you experience multiple jellyfish stings. Check some symptoms below:
- Chest pain
- Dysphagia (swallowing problems)
- Skin blisters
- Muscle cramps
- Trouble breathing
- Nausea
- Vomiting
- Abdominal (belly) pain
- Hyperhidrosis (excessive sweating)
Causes
Typically, jellyfish do not sting humans, but if you are swimming in the ocean or walking on the beach, you are at increased risk of coming into contact with nematocytes. When it occurs, the jellyfish releases its venom into your body. Thus, this poisonous substance may negatively affect your skin and may also enter your bloodstream. Usually, the severity of the symptoms depends on how much of the skin touches the venom.
While all jellyfish have tentacles, not all of them have powerful nematocytes. For instance, moon jellyfish live in all the world’s oceans, but they do not have long and poisonous tentacles. Moreover, a moon jellyfish sting often causes mild symptoms that disappear without treatment.
What Are The Potential Complications of a Jellyfish Sting?
In some cases, a jellyfish sting may cause serious and even life-threatening complications. Check some examples below:
- Delayed reactions – These include skin rash or blisters that may appear within 7 days after a jellyfish sting.
- Tissue damage – For example, ulceration, permanent scarring, or severe skin necrosis in the affected area of the skin.
- Secondary infections – Some people may develop bacterial infections from scratching open wounds or blisters.
- Irukandji syndrome – This is a serious complication in which people experience extreme lower back, chest, and muscle pain. Sometimes, it may also cause hypertension (high blood pressure) and heart problems.
- Cardiovascular collapse – This includes cardiac arrest, severe arrhythmia (irregular heart rhythm), or heart failure due to a box jellyfish sting.
- Anaphylaxis – This is a severe allergic reaction that requires immediate treatment. Otherwise, it may lead to death or permanent damage.
This article does not contain a full list of complications. In any case, you can talk with physicians about preventive measures.
Is There a Way to Prevent Jellyfish Stings?
Unfortunately, it is not always possible to prevent a jellyfish sting. However, doctors may recommend the following tips to reduce the risk. Examples include:
- Ask park rangers or lifeguards if any jellyfish are present around the beach.
- Wear a protective bodysuit if you surf or dive in the ocean.
- Do not touch a jellyfish that is washed up on shore because they still have venom in their tentacles that can sting on direct contact.
Diagnosis
In most cases, a jellyfish sting does not require treatment, but if you seek medical care, physicians can diagnose it during a physical examination. When symptoms do not disappear within 10 days, doctors may perform some tests to determine the appropriate treatment.
Treatment
Most of the time, people do not need treatment. However, you can take first aid for most jellyfish stings. Check some examples below:
- You should wash tentacles and venom off the affected part of the body with seawater. Do not use freshwater because it may worsen the symptoms.
- Remove the jellyfish tentacles you see in the skin with gloved hands or tweezers.
- To reduce the symptoms, it is recommended to apply vinegar or rubbing alcohol to the affected area. Do not use vinegar if you think you were stung by a Portuguese man-of-war jellyfish.
- Doctors may also recommend Calamine lotion, Hydrocortisone cream, ice packs, or hot water to relieve the symptoms
In more severe cases, doctors will prescribe pain relievers, antivenin, and antihistamines to reduce itching.
Frequently Asked Questions
How long does a jellyfish sting last?
Most mild jellyfish stings improve within a few hours, although pain, redness, itching, or skin irritation may last for several days. More severe stings can cause symptoms that persist longer and may require medical treatment.
Can a jellyfish sting be fatal?
Although most jellyfish stings are mild, certain species, particularly some box jellyfish, can cause life-threatening heart problems, breathing difficulties, or cardiovascular collapse. Severe symptoms require emergency medical attention.
Can a jellyfish sting through a swimsuit?
Yes, jellyfish tentacles can sometimes release venom even when they come into contact with covered skin. Wearing protective clothing designed for swimming or diving can reduce the amount of exposed skin and lower the risk of stings.
Should I urinate on a jellyfish sting?
No. Urine is not a recommended treatment for jellyfish stings and may not neutralize the venom. First aid depends on the species and location of the sting, so seawater rinsing and careful removal of visible tentacles are generally recommended unless local medical guidance says otherwise.
Can a dead jellyfish still sting?
A jellyfish that has washed onto the beach or appears to be dead may still have functional stinging cells in its tentacles. Avoid touching it with bare hands.
Should I use ice on a jellyfish sting?
Cold packs may help relieve pain from some jellyfish stings, but first-aid recommendations can vary depending on the species involved. In some cases, hot-water immersion is preferred for pain relief. If the jellyfish species is known, follow guidance from local lifeguards or medical professionals.
When should I go to the emergency room for a jellyfish sting?
Seek emergency medical care if a sting causes trouble breathing, chest pain, severe pain, vomiting, difficulty swallowing, muscle cramps, fainting, confusion, widespread swelling, or other serious symptoms. Call 911 immediately if the person has signs of a life-threatening reaction or becomes unconscious.
Can a jellyfish sting cause an allergic reaction?
Some people may develop an allergic reaction to jellyfish venom. A severe reaction, known as anaphylaxis, can cause difficulty breathing, swelling of the face or throat, dizziness, or loss of consciousness and requires immediate emergency treatment.
Can you get stung by a jellyfish without seeing one?
Jellyfish and their tentacles can be difficult to see in the water, and detached tentacles may still contain active stinging cells. Therefore, a person may be stung without seeing the jellyfish responsible.
Can you get another jellyfish sting after being stung once?
Yes, being stung once does not prevent future jellyfish stings. In some people, repeated exposure may cause stronger reactions, so it is important to leave the water and seek medical attention if symptoms are severe or worsening. If you have additional questions, ask your physician.
