The sea is one of the attractions that makes Belize and many other places in the Caribbean so enjoyable for both visitors and those of us lucky enough to live here. But that sea also has its dangers. Forget about sharks, stingrays and moray eels. Probably its biggest underwater pest -- especially during the late spring -- is a condition known as pica-pica, which comes from jellyfish.

Outbreaks of pica-pica have been reported in Belize, including Turneffe, St. George's Caye and Placencia. SCUBA divers who wear wet suits are not immune, as the tiny creatures can get inside and make the condition even worse. It goes by many names, but there's no confusing the discomfort and disfigurement that first hits only after you've left the water.

Pica Pica and the effects are actually caused by the offspring of the thimble jellyfish which appear in the millions around April or so.

Many people think that the thimble jellyfish is the actual culprit of the stinging, however Adult thimble jellyfish do not cause any sting. But in the spring season, the thimble jellyfish are doing the wild thing and their offspring, which are microscopic, are the real culprits of the rashs and stings.

People think that by wearing a wetsuit will protect the wearer, but because the offspring are very very small when the wetsuit fills up with water the critters are in the water and still sting.

So how do we battle these little monsters?

Normal areas affected are the under arm area stomach under the chin and neck area.

Vaseline is very good as it forms a protective layer over the skin. However, be careful not to use Petroleum vaseline if you are using a a silicone mask as it will disintegrate the silicone. So only use non petroleum vaseline.

That is a preventative measure, but what if you have already been stung?

A vinegar solution is best to neutralize the stinging cells. Just apply to sensitive areas immediately after getting out of the water, then apply a good antihistamine cream to the area to stop the itching. Bring some Diprosone Cream with you or pick some up at a local pharmacy, it's the most effective relief for the itch from pica pica!!! Or use Eurox lotion on your skin and if it's a bigger problem, use Eurox and buy Atarax antihistimines. Avaiable over the counter.

It seems the reaction gets worse with each repeated exposure.

Here's a couple experiences with pica pica...

We dove off Ambergris 5/3-5/9 and I experienced a bout with what we decided was pica pica. I wore a wetsuit skin and never got in the sea otherwise. What I first thought was a sunburn on my neck and chest, I realized was more puffy and red, like poison oak. I also had little bumps on my arms and legs, like goosebumps. It was not that uncomfortable but my neck was especially itchy and hot. All symptoms decreased in a few days and were not severe enough to interfere with my activities. The local response was "Windex" or anything with ammonia in it. I think that remedy is only for the cooling evaporative effect, although it probably wouldn't hurt after diving anyways. We went into the swimming pool after each dive just to refresh, so I think the pica pica reaction was already underway and ammonia bathing wouldn't be any different than chlorine bathing. We had some packets of cortisone cream in our first aid kit and that gave me the most relief. (Aloe vera gel felt good but wore off quickly.) After that stash was depleted, we went to the big supermarket for more cortisone cream and found it in the form of "Summer's Eve" female personal itching cream. What the heck, it worked! Expensive, though.

This was not a severe allergic reaction, just uncomfortable and unsightly. Our dive master before each dive slathered his neck and chest with vaseline and sunblock, he said to let the jelly babies slip off. I did it too, after being itchified. One of our dive companions said that letting off a big blast of air before surfacing can blow aside any floating irritants. Sounds useful if possible. In general, don't worry, just bring creams and have a great AC trip.WE DID!

I was in AC recently and found that putting waterproof SPF 45 worked great...only got 1 tiny hit on the lip with I spit my Regulator out...

When you get out of the water use windex if you get hit..the local divers know where to dive and will do all they can to steer you away from them...

Don't sweat it...they are mostly on the top of the water from what I saw...

Enjoy your trip...just ask the dive masters when you get there about them...they don't like getting hit either...trust me

I was there from 5/5 to 5/13 and was in the water numerous times a day. Never had any problems! None of us saw any pica pica, nor did we hear of anyone else having problems with them.....

I used Safe Sea when I was in AC from May 11th to the 20th. I didn't get hit from anything, whether swimming, snorkeling, or scuba diving ( and didn't wear a wetsuit as the water felt great, even at 80 feet.)

You can read about it at: http://www.nidaria.com/ , and get it at: https://www.tourism-and-fairs.com/niddata/order.html or Discountdiver.com, as I deleted the link after I bought it, but it's the best 15 bucks I ever spent. Maybe normal sunscreen would have worked just as good ( no one else in our group got hit,some used the safe sea and some used coppertone) but for 15 bucks, why take chances.

Discussion with Doctors

Peter Craig, Clinical Dermatologist
"These adult jelly fish have small larva stages about the size of a pin head. And at times there are hundreds of these larvae in the sea. On exposure to these larvae, they get trapped into the swimming gear, the swim trunks, or bikinis. The causative factor is the release a nematocyst, which is a protective part of all of these creatures. It releases a harpoon with a thread under intense pressure that penetrates into the skin and into the dermis, and there you have the reaction beginning. The tip of this harpoon has toxins on it and it's our body's response to these toxins, which causes the clinical presentation."

That clinical presentation includes very intense itching, bumps and skin rashes that occurs once the person reaches the water. Some victims even experience fever and nausea. Just as the condition is known by various names, like sea bather's eruption and sea lice, according to James Azueta, of the Fisheries Department, pica-pica also has more than one suggested cause.

James Azueta, Co-ordinator, Ecosystems Management Unit
"Pica-Pica is actually caused by neurotoxins produced by bacterial blooms. This bacteria is also known as blue green algae. They do bloom during the hot weathers, we're getting into the hot months here in Belize and they do bloom at the same time with the sea thimbles, which are actually minute jellyfish. We cannot see the toxins in the water, but we can feel the effects, and we tend to blame the thimbles as pica-pica."

"The doctor was actually explaining to you the effects of jellyfish, where they actually stinging cells. The stinging cells, what they call nematocysts, they are the ones responsible. They go into the flesh and they stay in there then they have a reaction with the body. The body just tries to defend itself, that's why it itches and it swells and everything. That's common for the body to react to foreign bodies."

Jose Sanchez
"So the outbreak that we have right now (May 2001) could be a combination of both."

James Azueta
"It could be a combination of both."

Peter Craig
"The treatment of sea bathers eruption or pica-pica involves the use of topical creams and we use topical steroids. People with severe cases will need a short course of oral steroids for about five or seven days. There is a commercial preparation that people can buy over the counter, it's hydro cortisone cream that is one percent. That can be used, but in severe cases you will need a stronger topical steroid that is available by prescription."

Jose Sanchez
"And it lasts for how long?"

Peter Craig
"The eruption will last for two to three weeks and the bumps will eventually disappear."

Jose Sanchez
"What can people to avoid pica-pica and the sea thimbles?"

James Azueta
"They should avoid areas of high concentration, with what we call sea moss. You can see them on calm days on top of the water, so just try to avoid these areas."

It's important to remember that there is no product you can use to prevent an eruption once you run into the pica-pica.

How to Treat Jellyfish Stings

Dr. Jorge López Granja, Dermatologist

Jellyfish stings can vary greatly in severity. Most often they result in immediate pain and red, irritated marks on the skin. Some jellyfish stings may cause more whole-body (systemic) illness, and in rare cases, are life-threatening. Most jellyfish stings get better with home treatment, but severe reactions require emergency medical care. Here’s Dr. Lopez’ professional advice about the topic.


Jellyfish tentacles contain microscopic barbed stingers (nematocysts). Each nematocyst is made up of a tiny bulb that holds venom and a coiled, sharp-tipped tube. The jellyfish uses the venom to protect itself and kill prey.

When something comes in contact with the tentacle — a fish or a human — tiny triggers on the surface of the tentacle release the nematocysts. The sharp tube penetrates the skin and releases the venom, which affects the immediate area of contact and may enter the bloodstream.

Jellyfish that have washed up on a beach may still release venomous stingers if touched.


The following tips can help you avoid jellyfish stings:

Wear a protective suit. When swimming or diving in areas where jellyfish stings are possible, wear a wetsuit or other protective clothing.

Avoid water during jellyfish season. Stay out of the water when jellyfish numbers are high.

Don't dive in. To avoid stings on the face, don't dive into waters that may have jellyfish.

If you’re stung, leaving the water as calmly as possible, rather than splashing about, may prevent further activation of stingers.


A reaction to a jellyfish sting can vary in severity. The reaction may be more severe depending on:

  • Species of jellyfish
  • Age and size of the person - Duration of expusure
  • Area of skin affected.

Common signs and symptoms include:

  • Immediate burning pain or itching
  • Red, brown or purplish tracks on the skin
  • Tingling and numbness
  • Throbbing pain that may radiate up a leg or arm to the torso

If left untreated the symptoms generally resolve within one to two weeks. Discoloration of the skin may last one to two months.

Severe jellyfish stings can cause a widespread (systemic) reaction. These reactions may appear rapidly or several hours after a sting. Signs and symptoms of severe jellyfish stings can include: nausea, vomiting, headache, weakness, difficulty breathing, irregular heartbeat, muscle spasms. If this happens seek medical treatment right away.

First Aid

Most jellyfish stings can be treated with relatively simple at-home remedies:

  • Remove tentacles. Remove any remaining pieces of tentacle by washing the area with seawater. Avoid using fresh water and also avoid touching the tentacles with your hands. Preferably, use an object like a credit card to gently brush it off. Careful: rubbing it off with a towel or clothing is likely to cause the discharge of more venom.
  • Deactivate stingers. If you are sure it is not a Portuguese Man-of-War sting, then generously rinse the affected area with white vinegar (acetic acid 3-10%) for at least a minute, which may deactivate the stingers. The treatment of choice for Portuguese Man-of-War stings is to apply a paste made of baking soda and seawater. Don’t use vinegar on a Portuguese Man-of-War sting as it can cause discharge of nematocyst. If nothing else is available, apply seawater followed by hot water for 15-20 minutes regardless of the species of jellyfish.
  • Relieve pain or irritation. Recent studies have suggested that soaking the affected area in tolerably hot fresh water for at least 20 minutes — after a vinegar or baking soda + seawater treatment — may be more effective in pain relief than cold packs, because the heat may decrease the potency of the venom. The temperature should be between 104 and 113 F (40 and 45 C).
  • If you do not know what type of jellyfish stung you, the safest bet is to rinse thoroughly in salt water, followed by soaking in hot water followed by lidocaine cream or calamine lotion.

Remedies to Avoid

  • Human urine, because it is inconsistent and it can have the same effect as fresh water, releasing more venom from the stingers
  • Meat tenderizer has not been scientifically proven effective
  • Methylated spirits, vodka or alcohol in any form may cause rapid massive discharge of stingers (nematocysts).
  • Fresh water: causes rapid discharge of stingers as well
  • Pressure bandages
  • Pain relievers because they will have little effect on that type of pain and they may mask a more serious reaction

When to see a doctor

Although jellyfish stings can be quite painful, most are minor and get better with home treatment.

Seek emergency treatment if:

  • Stings cover large areas of skin
  • You have any systemic symptoms or a severe reaction
  • Stings affecting the eyes
  • Difficulty breathing, difficulty swallowing, chest pain, or intense pain at the site of the sting.
  • If the sting happened to someone who is very young or old.

Types of jellyfish

While many types of jellyfish (such as the Moon jellyfish and the Cannonball or Cabbage Head jellyfish found in Belize) are relatively harmless to humans, others can cause severe pain and are more likely to cause systemic reactions. Types of jellyfish known to cause more-serious problems in people include:

Sea nettles. Common in both warm and moderately cool seawaters.

Portuguese man-of-wars/Bluebottle jellyfish. (Although this is not a jellyfish, but a siphonophore, it is included here due to the similarity in symptoms). These species live mostly in warmer seas (tropical and subtropical Pacific and Atlantic oceans). A Portuguese man-of-war has a blue or purplish gas-filled bubble that keeps it afloat on the surface of the water and acts as a sail.

Lion's mane jellyfish. These are the world's largest jellyfish. The body of a lion's mane can reach a diameter of 10 feet (3 meters). They are most common in cooler, northern regions of the Pacific and Atlantic oceans.

Box jellyfish. Also called sea wasps, box jellyfish are generally the most harmful jellyfish to humans and can cause significant pain. Life-threatening reactions are more common with these species. The more dangerous species of box jellyfish are found in the warm waters of the Pacific and Indian oceans.

Beware of the Pica Pica! Jellyfish Abundant During Easter Season

Many explain it as having hundreds of mosquitoes biting you all over at the same time. Most of the time you will not be aware that you have been stung by the hundreds of Thimble Jellyfish that you have come in contact with. Spring/Easter season brings the ‘Pica Pica’ jellyfish to the shores of Belize.

The Thimble Jellyfish make their appearance to the shores of Belize during the windy days between March and May, but its not uncommon to find these jellyfish from late January all the way to June. They suddenly arrive when the high winds and strong currents start making their way into the area.

The Thimble Jellyfish is locally known as the Dedal and the discharge of their larvae is called the Pica Pica, although locals call the jellyfish Pica Pica. It is this discharge that contains the stinging cells that will cause a skin irritation. Many will find that playing with the actual jellyfish will not cause any skin irritation unless they are releasing their larvae.

This marine animal is a small jellyfish resembling a thimble that measures about 1" in diameter and is conspicuously mottled with dark brown markings. They appear in dense aggregations which are transported by winds and current.

So if you are planning of having some fun in the sea during this time of year in Belize, BE WARNED and make sure you keep away from them.

Why Is There A Need For A Warning On The Thimble Jellyfish?
Accidental contact with this jellyfish causes a skin rash known as sea bathers eruption. This dermatitis is characterized by the acute appearance of small itchy erythmas that may, in some cases, evolve into pustules. This eruption occurs predominantly on body areas that are covered by the bathing suit or subjected to pressure or rubbing, such as armpits, neck, groin and inner thighs. In some cases the dermatitis includes chills, fever nausea, headache and weakness, particularly in children. Symptoms don not appear until hours (1 to 24) after leaving the water. Because of this, sea bathers eruption is sometimes confused with viral gastroenteritis or varicella (chicken pox). The lesions usually persist from a few days to weeks, after which they spontaneously heal.

Some Preventative Measures.
Persons with histories of allergies should avoid swimming in waters infested with Thimble Jellyfish. Swimmers who must risk exposure should avoid the use of T-Shirts as they trap the thimble Jellyfish between skin and clothing thus increasing the severity of the reaction. After exposure to seawater, swimmers SHOULD NOT SHOWER WITH FRESH WATER. Fresh water triggers the stinging cells. It is advisable to change out of bathing suit as soon as possible and apply vinegar which neutralizes the nematocysts that cling to the skin but have not yet released their toxins. Bathing suits should be thoroughly washed with detergent as symptoms may recur if contaminated suits that were poorly washed are re-worn.

Is there Treatment?
When the lesions are minimal the application of creams and lotions to reduce the rash is recommended. The use of antihistamines is often helpful but should not be done without consulting a physician. In severe cases, topical and systemic steroids may be used but always under medical supervision. IMORTANT, DO NOT SCRATCH the affected areas because this can lead to skin infections.

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