What is the Portuguese caravel, why it can be lethal, and what to do if it stings you?
In the Mediterranean, sightings of Portuguese caravels, “alien” organisms from the Atlantic Ocean, are increasingly frequent. Here's what we know.
In recent days, a bather from Catania had an unfortunate close encounter with the tentacles of a Portuguese caravel (Physalia physalis), due to which she developed severe symptoms and was rushed to the intensive care unit of the Policlinico San Marco hospital. The presence of this marine organism, often mistakenly confused with a medusa it is only occasional in the Mediterranean Sea however, the sightings have increased significantly in recent years, especially in the waters of Sicily.
Here the Portuguese caravels arrive carried by the wind and currents after entering the Mediterranean from the Atlantic Ocean, across the Strait of Gibraltar. The accident that took place in Catania is not the first in Italy nor the most serious; in 2010 a 69-year-old was stung and killed by a Portuguese caravel while bathing in Villaputzu, in southern Sardinia. To date, she is considered the probable first victim of this organism in the Mare Nostrum. But what exactly is a Portuguese caravel?
Credit: Andrea Centini
What is the Portuguese caravel?
The Portuguese caravel is a marine animal belonging to the phylum dei coelenterates, which include jellyfish, corals, hydrozoans, and other organisms. It is classified as siphonophores set of four distinct organisms (the zooids) who live in symbiosis, strictly dependent on each other to allow survival. The appearance is unmistakable: out of the water, it is visible pneumotoforo, a bag filled with brightly colored gas - from blue to violet, passing through pink - which allows the animal to float.
Below it is the very long stinging tentacles, which can reach tens of meters in length. In the most extreme cases even 30 - 50 meters. Thanks to them, the Portuguese caravel can trap its prey with a "deadly embrace" and feed itself, as shown in the following image taken in the Atlantic, in front of the Azores islands.
Credit: Andrea Centini
Since it behaves like a planktonic organism, which does not swim actively but lets itself be carried away by currents and winds, it happens that following adverse weather conditions it can easily reach the coasts, where the risk of accidents is significantly higher. At the end of last year, several specimens ended up beached after a storm on the Lancashire seafront, near Blackpool (United Kingdom).
Because it can be lethal
The stinging poison of the Portuguese caravel is considered one of the most powerful and dangerous marine fauna. It is not as lethal as that of cubomeduse Australian but can have lethal consequences in particularly sensitive and vulnerable individuals.
"If it is robust, and if the sting occurs while the animal is fishing, the symptoms, in the victim, are very strong, similar to those of a very strong electrical discharge, and the sign that remains is like that of a hot iron resting on the skin ”, Professor Ferdinando Boero, an expert in coelenterates and professor of Zoology and Anthropology at the Federico II University of Naples, told ANSA on the occasion of the fatal accident in Sardinia.
In the case of the woman from Catania, they have recently developed headache, retched, severe cardiac arrhythmia, asthenia e respiratory difficulties which led her to be admitted to intensive care. "Such important symptoms and characteristic skin lesions on the back, buttocks, and legs suggest that it is the sting of a Portuguese Caravel," said Dr. Benedetta Stancanelli, chief physician of the hospital. The reaction in sensitive subjects, in addition to the excruciating pain caused by the poison released into the skin, can lead to paralysisall'cardiac arrest, and anaphylactic shock.
What to do in case of a sting?
First of all, it must be emphasized that, when a jellyfish or a similar organism stings us with its stinging tentacles, it is not attacking us; we simply bumped into it or the animal ended up on us, without any aggressive intent. In other words, it's just bad luck. In case of a puncture, it is essential to keep calm and not panic, also because the pain can be unbearable and in predisposed subjects, anaphylaxis, is a life-threatening allergic reaction.
If you are in deep water it is important to swim back, get on a boat or get help from someone, but not to stay in place. As explained by Dr. Antonio De Bitonto, Head of the Dermatology Operating Unit at the San Marco Polyclinic of the San Donato Group, once ashore it must be checked that there are no pieces of the animal attached to the body, which must be removed very carefully.
Gloves should be worn if you use your hands, but a thin, stiff object like a credit card is better. After removing the animal residues, the affected area should be rinsed with sea water; not fresh water which can favor the outbreak of any nematocysts left on the skin, resulting in the release of further toxins.
Not even pee, ammonia, and other "grandmother's remedies" should be used which only risk worsening the inflammation. The authoritative MSD Manuals for Healthcare Professionals recommend not using vinegar before seawater for the sting of a Portuguese caravel, recommended instead for those of other coelenterates it is necessary to seek specialist health care and go to an emergency room in case you do not feel well after the sting.
