Can coral polyps actually grow in human skin after contact during diving. How long do coral-related skin infections last. What are the symptoms and treatments for skin injuries from coral reefs.

The Myth of Coral Polyps Growing in Human Skin

Many scuba divers have wondered if coral polyps can actually grow inside human skin after contact with a reef. This intriguing but alarming idea has circulated in diving communities, causing concern for some. But is there any truth to it?

The short answer is no – coral polyps cannot grow and survive inside human skin. While coral injuries can cause persistent and unusual symptoms, the idea of living coral taking root in a diver’s body is a myth. Let’s explore the reality behind coral-related skin injuries and infections that divers may experience.

Common Causes of Skin Injuries While Diving

Divers often sustain minor cuts, scrapes and abrasions during their underwater adventures. Some common causes include:

• Brushing against sharp coral or rocks
• Grabbing reef structures in strong currents
• Contact with fire coral or other irritating marine life
• Scrapes from wreck penetration or cave diving
• Equipment issues like mask or fin chafing

These injuries may seem minor at first but can develop into more serious problems if not properly treated. The marine environment harbors many microorganisms that can infect even small wounds.

Symptoms of Coral-Related Skin Infections

When coral injuries become infected, they can produce some alarming and persistent symptoms:

• Redness, swelling and pain around the wound site
• Oozing or discharge from the injury
• Slow healing or worsening over time
• Skin sloughing or peeling in the affected area
• Itching, burning or tingling sensations
• Formation of small bumps or pustules

These symptoms may last for weeks or even months in some cases. The unusual appearance and persistence of coral-related infections likely contributed to the myth of coral growing inside the skin.

Why Do Coral Injuries Become Infected So Easily?

Coral-related skin infections tend to be more problematic than typical cuts and scrapes for several reasons:

1. Coral structure: The rough, porous surface of coral can leave tiny fragments embedded in the skin.

2. Marine bacteria: Seawater contains numerous microorganisms that can colonize wounds.

3. Coral toxins: Many coral species produce chemicals that can irritate human skin and impair healing.

4. Delayed treatment: Divers may not notice minor injuries until hours after exiting the water.

5. Warm, moist environment: Tropical climates promote bacterial growth in wounds.

Treatment Options for Coral-Related Skin Infections

Proper care is essential for coral injuries to prevent infection and promote healing. Here are some treatment approaches:

1. Clean the wound thoroughly with fresh water and mild soap
2. Apply an over-the-counter antibiotic ointment like Neosporin
3. Keep the area clean and dry between water activities
4. Use hot water soaks to help neutralize coral toxins
5. Take oral antibiotics if prescribed by a doctor for serious infections
6. Seek medical attention for wounds showing signs of spreading infection

For persistent or severe cases, a doctor may need to debride (remove dead tissue from) the wound to promote healing.

Preventing Coral-Related Skin Injuries While Diving

An ounce of prevention is worth a pound of cure when it comes to coral injuries. Divers can take several precautions:

• Wear a full-body wetsuit or rash guard for skin protection
• Use reef hooks instead of grabbing coral in strong currents
• Practice good buoyancy control to avoid accidental contact
• Be aware of fire coral and other irritating species
• Rinse any small cuts or scrapes with fresh water after diving
• Pack a basic first aid kit for dive trips

By taking these steps, divers can greatly reduce their risk of problematic coral-related skin injuries.

Other Marine Life That Can Cause Skin Infections

While coral receives much attention, other marine organisms can also cause persistent skin problems for divers:

Fire Sponges

These brightly colored sponges contain toxic compounds that can cause intense burning and itching on contact. Symptoms may persist for weeks.

Hydroids

These tiny creatures resemble delicate plants but can deliver painful stings. Some species cause long-lasting skin irritation.

Sea Urchins

The long spines of sea urchins can break off in the skin, leading to inflammation and possible infection.

Jellyfish

While most jellyfish stings heal quickly, some species can cause recurring skin eruptions weeks after the initial contact.

Divers should familiarize themselves with potentially harmful marine life in the areas they plan to explore.

When to Seek Medical Care for Diving-Related Skin Problems

While many coral injuries and marine life encounters can be managed with basic first aid, some situations call for professional medical evaluation:

• Signs of spreading infection like red streaks or swollen lymph nodes
• Fever or chills developing after a diving injury
• Wounds that worsen or fail to improve with home treatment
• Severe pain, swelling, or loss of function in the affected area
• Any neurological symptoms like numbness or muscle weakness
• Allergic reactions such as difficulty breathing

It’s always better to err on the side of caution when dealing with marine-related injuries, especially in remote tropical locations where access to medical care may be limited.

Distinguishing Fact from Fiction in Diving Injury Lore

The diving community is rife with colorful stories and questionable advice about marine injuries. How can divers separate myth from reality?

Consult Reputable Sources

Look for information from established diving organizations, marine biology experts, and medical professionals specializing in diving medicine.

Be Skeptical of Extraordinary Claims

If something sounds too bizarre to be true (like coral growing in human flesh), it probably is. Extraordinary claims require extraordinary evidence.

Consider the Biological Plausibility

Think critically about whether a claim makes sense from a biological standpoint. Could coral really survive in human tissue?

Seek Multiple Perspectives

Don’t rely on a single anecdotal account. Look for consensus among multiple credible sources.

Stay Up-to-Date

Our understanding of marine life and diving medicine continues to evolve. Be open to new information that challenges old beliefs.

By applying critical thinking skills, divers can avoid falling for sensationalized myths while still respecting the very real risks posed by marine life encounters.

The Fascinating World of Coral Biology

While coral polyps can’t grow in human skin, these tiny creatures are remarkable in their own right. Understanding coral biology can enhance a diver’s appreciation for reef ecosystems:

Coral Polyp Structure

Coral polyps are tiny, soft-bodied animals related to sea anemones and jellyfish. They secrete a hard calcium carbonate skeleton that forms the structure of coral reefs.

Symbiotic Relationships

Most reef-building corals have a mutually beneficial relationship with algae called zooxanthellae, which live within the coral tissues and provide nutrients through photosynthesis.

Reproduction

Corals can reproduce both sexually and asexually. Many species engage in spectacular mass spawning events, releasing eggs and sperm into the water in synchronized displays.

Growth Rates

Contrary to the rapid growth imagined in skin infection myths, most corals grow very slowly – often just a few centimeters per year.

Environmental Sensitivity

Corals are highly sensitive to changes in water temperature, acidity, and pollution levels. This makes them important indicators of overall ocean health.

By learning about coral biology, divers can better understand the delicate nature of reef ecosystems and the importance of conservation efforts.

In conclusion, while coral-related skin infections can be persistent and troublesome for divers, the idea of coral polyps actually growing inside human skin is purely mythical. By understanding the real risks, taking proper precautions, and seeking appropriate treatment when needed, divers can safely enjoy exploring the underwater world of coral reefs and other marine environments.

Can coral polyps grow in your skin?

Cacia

Contributor

• Dec 22, 2005

• #1

It has been a couple weeks….I had to grab a ledge (at the direction of our Palau guide, in a stiff current, with a big camera) and thought I had a “barren spot” but I came out with little nicks that turned into oozing festering wounds that are now sloughing like a spider bite, the skin sloughing off. It is like aliens are in there, trying to get out. Somebody yesterday on the boat said coral can live in your skin and you have to get it cut out. Is this true? How long should I wait? Messing up my holiday manicure schedule.

Rick Murchison

Trusty Shellback

• Dec 22, 2005

• #2

catherine96821:

It has been a couple weeks….I had to grab a ledge (at the direction of our Palau guide, in a stiff current, with a big camera) and thought I had a “barren spot” but I came out with little nicks that turned into oozing festering wounds that are now sloughing like a spider bite, the skin sloughing off. It is like aliens are in there, trying to get out. Somebody yesterday on the boat said coral can live in your skin and you have to get it cut out. Is this true? How long should I wait? Messing up my holiday manicure schedule.

Click to expand…

There are aliens in there, but they aren’t coral polyps. What you get from scraping skin against things under salt water are a host of bacteria, and a veritable soup of toxins, depending on what critters were living on the surface where the scrape occurred. Hot water may denature some of the toxins; a good topical antibiotic (like Neosporin) can help fight the bacteria.

Sometimes, however, you’ll get toxins in there that just have to run their course, and you may be sloughing skin for a month or more. If the topical doesn’t reduce painful swelling and redness, and

especially if you get any red streaking from the wound then take it to an MD. Some of these critters can be serious.

Rick

“You can have peace, or you can have Freedom. Don’t ever count on having both at once.” (Heinlein)
“… they saw the deeds of the LORD, his wondrous works in the deep.” (Ps107:24)

Rick Murchison

Trusty Shellback

• Dec 24, 2005

• #3

All clear now Catherine?

Rick

“You can have peace, or you can have Freedom. Don’t ever count on having both at once.” (Heinlein)
“… they saw the deeds of the LORD, his wondrous works in the deep.” (Ps107:24)

Diver Dennis

Contributor

• Dec 24, 2005

• #4

I just had a bunch of green dead flesh cut out of a wound I got in a wreck in Truk a few days ago. I’m not sure what it was but I’m on antibiotics as of this afternoon.

Diver Dennis

Contributor

• Dec 24, 2005

• #5

I know how stiff the currents can be in Palau in certain ares. Was it Blue Corner? I was using 2 reef hooks to take photos.

drbill

The Lorax for the Kelp Forest

• Dec 25, 2005

• #6

Agree with Rick on this. I had a serious infection while diving in Fiji a few years back. Fortunately I take Cipro with me and once I started taking it, the infection subsided (although there are still two small scars).

As a biologist, it would be quite incredible if coral polyps were growing under your skin. But then we’ve found they grow in the deep dark ocean.

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Dr. Bill: Not THAT kind of doctor… but I’ll take a look at it anyway!
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Cacia

Contributor

• Dec 27, 2005

• #7

Rick, Dennis, Dr Bill

Thanks for the feedback. Nope, it is still very strange. Not like infected exactly, I guess I will eventually get it looked at. I contacted some fire sponge in The Rhone (Tortola) last year that caused some sloughing. Even the joints are swollen. I am an RN and I am pretty sure a physician will just say to put Neosporin on it.

Dennis, great Manta shot. Yes, one day the current was smokin’ and the guide said in our briefing that the plan was to not hook in. Well, he changed his mind because we saw some amazing shark action. He had everyone grab the wall which I have done many times with the hook. Since I had a big camera set up and a very low on air boyfriend……. I think I will post this in Photography Forum as “Photographers make the Worst Buddies” ……to be continued

Mike Veitch

Contributor

• Dec 27, 2005

• #8

He he he. ….

SO many dives in Micronesia and nary an infected wound…

By the way, Catherine and Dennis, you guys were there at the same time and you both know me….strange little world….

Nice sharks Catherine

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Diver Dennis

Contributor

• Dec 27, 2005

• #9

Mike I think the betle nut has saved you from any wound infection. Too bad we passed in the night Catherine, maybe next time. I actually had another wound on my leg get infected yesterday but it seems to be subsiding now.

Diver Dennis

Contributor

• Dec 27, 2005

• #10

Nice shark action by the way.

Coral Scrapes and Cuts – Divers Alert Network

Cuts and scrapes are the most common injuries incurred by divers and snorkelers. DAN receives about one inquiry a week related to someone who has come into contact with coral. A burning sensation, pain and itching are common and may also be accompanied by a rash. These injuries can have a latent evolution and take weeks or months to heal, confusing both patients and clinicians.

Mechanisms of Injury

Soft living tissues cover the surface of corals. In the case of stony corals, the rigid (abrasive) structure underneath makes the coral’s soft tissue easy to tear and get into the scrape or cut. Foreign material can prolong the wound-healing process since the different antigens and substances cause an acute inflammatory process and infection. Cuts and scrapes from sharp-edged coral and barnacles tend to fester and may take weeks or even months to heal. Granulomas can form if debris from the original wound remains in the tissue. The body attempts to remove it, resulting in an itchy rash or papule (small, raised, tender bump) that lasts for some time before the body eliminates it.

While most “raspberries” generally heal quickly, skin abrasions from a marine environment can sometimes be more challenging to treat than those we get from outdoor activities such as baseball or bicycling. Whether it is a coral, a rock or a wreck, they all share a common factor: They are covered by living marine organisms, which makes coral cuts and scrapes unique.

Manifestations

The extent of the reaction depends on the presence and amount of toxins, the size and location of the abrasion and the pre-existing sensitivity of the injured person. The most common manifestations are a burning sensation, pain and itching. A rash may accompany the injury if the coral is a hydroid, such as fire coral.

Most animals of class Hydrozoa become hydroids as a life stage. They are predominantly colonial, and while most of them are marine creatures, you can find a few species in freshwater environments.

Fire corals are cnidarians, so they contain nematocysts. Touching them with a simple rub can cause mechanical activation and envenomation. The manifestation is usually blistering, which typically appears a few hours after contact. They typically resolve in a few days, but it is quite common for these injuries to relapse within a week or two after what seemed to be healing progress. This delayed reaction is typical of these types of envenomations.

Prevention

When underwater, try to avoid contact with coral or any other living creature. Whenever possible, wear a wetsuit or dive skin to protect yourself if you are accidentally pushed into coral by another diver or a current. Ocean divers should consider a marine animal first aid kit for their travels. Ready supplies will speed up the time to properly administer first aid for injuries. Additionally, for divers who want to learn more about the various marine life injuries, there are courses in marine life identification, first aid courses and a variety of books and publications available.

First Aid

• Scrub the cut vigorously with soap and water, and then flush the wound with large amounts of water.
• Flush the wound with a half-strength solution of hydrogen peroxide in water. Rinse again with water.
• Apply a thin layer of antiseptic ointment, and cover the wound with a dry, sterile and non-adherent dressing. If you have no ointment or dressing, you can leave the wound open.
• Clean and re-dress the wound twice a day.
• If the wound develops a crust, use wet-to-dry dressing changes. Put a dry sterile gauze pad over the wound and soak it with saline or a diluted antiseptic solution (such as 1% to 5% povidone-iodine in disinfected water). Allow it to dry then rip the bandage off the wound. The dead and dying tissue should adhere to the gauze and lift free. The tissue underneath should be pink and may bleed slightly but should be healing. Change the dressings once or twice a day. Use wet-to-dry dressings for a few days or until they become non-adherent. Then resume the regular wound dressing described above.
• Look for any signs of infection: extreme redness, red streaks on the extremity, pain, fever, pus or swollen lymph glands. If you have any, consult a qualified health professional about starting an antibiotic. A possible Vibrio bacteria infection can cause illness and even death in someone with an impaired immune system (e. g., from AIDS, diabetes or chronic liver disease).
• Watch for coral poisoning, which can occur if abrasions or cuts are extensive or from a particularly toxic species. Symptoms include a wound that heals poorly or continues to drain pus, swelling around the cut, swollen lymph glands, fever, chills and fatigue. If you have these symptoms, see a physician.

Complications

The most frequent complications from non-stinging coral scrapes are inflammation (which leads to poor healing) and less commonly a secondary infection. Proper wound cleaning is crucial. If fire coral is the culprit, then a diluted acetic acid solution, such as household white vinegar, is a reasonable topical decontaminant and should be used as a soak to reduce the pain. Immersion in hot water can reduce the symptoms. Hot water is ideal, but you can use instant hot packs, cold packs or ice packs. Provide symptomatic treatment for the inflammatory response. Steroid creams are rarely helpful, and they can prolong a skin infection. If the inflammation is severe, you may administer systemic steroids in a moderate, tapering dose under the supervision of a trained medical provider. Oral antihistamines can sometimes help reduce the itching or burning sensation. 

Possible Complications of an Old Problematic Wound

It is not uncommon for divers to contact DAN concerned about a minor skin abrasion on their hands, knees or elbows that happened months ago and has not healed despite proper care. These chronic wounds often have a red and bumpy appearance, occasionally develop a crust and are usually painless. If common antibiotic ointments do not help, divers wonder if the cause may be a marine-specific pathogen.

Divers with an open wound, even a small cut or scrape, are at risk for skin infections. When an old problematic wound fits the descriptions above, it might have become infected with an opportunistic pathogen known as Mycobacterium marinum. Despite the name there are no marine-specific pathogens that affect humans. Some infections are more common in aquatic environments. M. marinum is responsible for a condition commonly known as fish tank granuloma, or aquarium granuloma.

The red and bumpy nodules, no larger than a centimeter, are granulomas — inflammatory immune cells trying to wall off the pathogen. Granulomas are usually isolated but can sometimes appear in small clusters. They are not necessarily painful. There may or may not be discharge from the wound.

Characteristics of

M. marinum That Affect Healing

• The pathogen is opportunistic. It causes infection only in the right conditions (environmental and patient-related), so it is often not considered as a potential culprit.
• It likes cooler temperatures, which is why these wounds tend to flourish in areas with lower body temperatures such as hands, knuckles, elbows and knees.
• Only specific antibiotics work, so the typical antibiotic treatments are usually unsuccessful.
• The life cycle is slow, which means treatments last a long time. Sometimes patients will abandon what could have been a successful treatment or doctors may look for other potential explanations for the symptoms.
• It requires specific culture media that a doctor would not ask for unless they suspected this pathogen. Standard culture results are often negative, which delays the diagnosis.

Allow your doctor to examine the wound and follow their standard procedures. The doctor will probably ask you how it happened or when it started. Tell them about the superficial abrasion in a marine environment. You may want to ask specifically if M. marinum could be the cause. Your doctor does not need dive-specific medical knowledge for this type of issue.

Fitness to Dive

Always take care of wounds and clean them thoroughly no matter the severity. The skin is our most effective and efficient means of immunological defense. A compromised wound can get seriously infected.

As a rule, treat wounds properly and let them heal before diving. This is particularly important before traveling to a remote location or one with limited local medical care capabilities. A skin lesion with the potential for infection might warrant a more conservative decision to stay ashore if you have such a trip planned.

Chronic skin lesions require specific consultation with your physician team before diving. Your doctor may prescribe treatment or a protective covering to prevent skin breakdown.

Beauties of the Red Sea: top 5 diving paradises

Warm, full of life, light and bright colors of the depths of the Red Sea never cease to amaze and delight both beginner divers and extreme divers. We invite you to take a trip to its most beautiful places.

Blue Hole

The Blue Hole in Dahab (Egypt) is a rounded sinkhole more than 100 meters deep, formed in a coral reef. The diameter of the Blue Hole is about 50 meters, it is located very close to the coast. The path to it, which takes no more than 30 minutes, runs along a picturesque sheer wall with faults, generously decorated with a variety of underwater plants. In the immediate vicinity of the entrance to the hole, the wall changes slope; tuna, the main food fish of the Red Sea, and predatory barracudas are often found here. Inside, the Blue Hole is made up of different types of corals: some of them have tentacle-like outgrowths, others form a huge wavy covering called “elephant skin”.

There are two ways to get to the open sea from the Blue Hole: through a dense coral garden growing at a depth of 7 meters, or by swimming out of a huge arch located at a depth of 55 meters. Both ways, according to experienced divers, leave indelible impressions. Despite the fact that the road to the Blue Hole dive site is surrounded by signs with the names of divers who did not return from it, the sinkhole remains one of the popular places for diving competitions.

The Blue Hole is located about 15 kilometers from the quiet resort town of Dahab, you can get to it by bus, rented car or taxi.

Thomas Reef

Thomas Reef, located near the Egyptian Sharm El Sheikh, will please the diver not only with colorful corals, encounters with turtles, goopers and crunks. The most interesting begins at a mark below 35 meters: there is a crack going down to a depth of 109 meters – Thomas Canyon. Its width does not exceed 3 meters, and with depth it only becomes narrower, so for inexperienced divers such a dive is not always pleasant. The canyon has 4 arches: at a depth of 50, 65, 75 and 90 meters. After passing each of them and looking up from the water column, you will witness the extraordinary glow created by the sunlight concentrated on the reef break.
You can get to the reef from Sharm El Sheikh by safari boat or daily boat.

Dahlag Archipelago

Eritrea, even at the height of the season, is not yet teeming with divers, so the underwater world of the Red Sea near its shores is virgin flora and fauna, the most ancient reefs of the Red Sea, majestic whales and sunken ships. The Dahlag archipelago is a national park in Eritrea, and only 4 of its 200 islands are inhabited by people, not seabirds. Having plunged into the sea near Dohul Island, which is part of the archipelago, you can observe the life of dugongs and green turtles, sharks, watch starfish and hedgehogs. In the waters of the northern part of Dissey Island, there are gardens of hard and soft corals that provide shelter for rays, barracudas, reef sharks and turtles. A shallow diving depth near the islands of the Dahlak archipelago makes it possible to dive not only during the day, but also at night. Overgrown with corals and resting near the main island of the archipelago, a naval base and a cargo ship are another attraction of Eritrea.

Paradise Reef

Located in Eilat, Israel, Paradise Reef is one of the rare places where you can dive directly from the shore. In shallow water, it’s impossible not to marvel at the 150-meter ridge of live acropora coral, but diving a little deeper, you will have the opportunity to meet toad fish, ribbon fish and groupers that live in the sea lilies, hydroids and anemones that grow here. At a depth of just over 25 meters, the reef abruptly breaks off, the seabed opens up with its mysterious inhabitants: ghost fish, needle fish, starfish.

Japanese Gardens Reef – Aqaba, Jordan

Japanese Gardens Reef (Aqaba, Jordan) is also a great place to dive right in front of the hotel. The main attraction of the reef is black coral bushes resembling trees, thanks to which the reef got its name. Corals grow at a depth of 5 to 20 meters, so a diver of any skill level can dive underwater and enjoy the contemplation of its many inhabitants – turtles, octopuses, dolphins, crabs, schools of colorful fish.

sunscreen that protects you can harm this magnificent coral reef

Scientists have bad news for vacationers: sunscreen that protects your skin while you swim or dive in the calm waters of tropical waters can destroy the very coral reef that surrounds it amazing marine life that you have come to admire.

Many sunscreens contain oxybenzone, a chemical that helps filter out UV rays that cause skin cancer. Unfortunately, studies show that the same substance also makes corals more susceptible to the bleaching that is damaging famous reefs around the world.

This is an example of how the use of synthetic chemicals can have unintended consequences, raising the importance of a more thorough risk assessment before they are used in industry. Many new substances, including oxybenzone, pass through wastewater treatment systems unaffected and end up in our rivers and oceans.

Some countries have already taken steps to protect the critical tourism industry.

“This is a case in which the precautionary principle should be invoked,” says Gabriel Grimsditch, marine ecosystems expert at the UN Environment Program in Nairobi. “Oxybenzone protects us from harm. But it is also a pollutant, and we need to know as much as possible about its properties before releasing it into the environment. There is already evidence that this substance is harmful to coral reefs.”

Oxybenzone is part of a family of chemicals often added to plastics to protect them from photo-degradation and to beverage bottles to protect the contents. They also retain the colors and scents of hundreds of products, including hair sprays, soaps and nail polishes.

Even though not tied to reducing the condition of corals, many countries have restricted the use of oxybenzone due to concerns that the substance could harm human health, such as causing skin allergies. Researchers are also studying its effect on hormone levels.

A recent burst of attention to its impact on marine life stemmed from a 2015 research article that states that approximately 14,000 tons of sunblock is washed off the skin of swimmers and divers every year across all coral reefs.

©: Dave Young

In laboratory experiments, the authors found that oxybenzone reduced the larval form of Stylophora pistillata corals to “ damaged pedunculate state ” and was toxic to five other coral species . They warn that the chemical “threatens the resilience of coral reefs to climate change.”

Some cosmetics companies already offer “reef-friendly” products that use zinc or titanium oxide instead of more controversial ingredients

Other studies indicate that the substance may also harm fish, sea urchins and mammals.

Some countries have already taken steps to protect their vital tourism industries. Mexico only allows “biodegradable” sunscreen in some of its major marine parks. Legislators in Europe and Hawaii have pushed for more sweeping bans. In the United States, the National Park Service encourages visitors to use alternative products or simply wear long-sleeved hats and swimwear.

Companies are fighting back, pointing out that other factors, including climate change and the release of nutrients and other pollutants from land to the ocean, are having a strong impact on the deterioration of coral ecosystems.

“There is no scientific evidence that, under natural conditions, sunscreen ingredients that have been used safely around the world for decades contribute to this problem,” the Consumer Health Products Association, which is a United States health care company that makes medicines available without a prescription.

However, some cosmetics companies already offer “reef-friendly” products that use zinc or titanium oxide instead of more controversial ingredients.