Fish skin used to bandage burns
Doctors at the José Frota Institute in Fortazela, Brazil are testing the skin of the fish tilapia as a bandage for second and third degree burns (Scientific American, 2017).
Animal skin has long been used in the treatment of burns in developed countries, but Brazil lacks human skin, pig skin, and artificial alternatives. The three functional skin banks in Brazil can meet only 1% of the national demand. Public health patients in Brazil are normally bandaged with gauze and silver sulfadiazine cream. Dr Jeanne Lee, interim burn director at the the regional burn centre at the University of California at San Diego, said “It’s a burn cream because there’s silver in it, so it prevents the burns from being infected. But it doesn’t help in terms of debriding a burn or necessarily helping it heal.” The gauze and cream dressing must be changed every day, which is a painful process.
Tilapia, is widely farmed in Brazil and its skin was, until now, considered a waste product. Unlike the gauze bandages, the sterilised tilapia skin goes on and stays on.
The first step in the research process was to analyse the fish skin. Dr Edmar Maciel, a plastic surgeon and burn specialist leading the clinical trials with tilapia skin, said “We got a great surprise when we saw that the amount of collagen proteins, types 1 and 3, which are very important for scarring, exist in large quantities in tilapia skin, even more than in human skin and other skins. Another factor we discovered is that the amount of tension, of resistance in tilapia skin is much greater than in human skin. Also the amount of moisture.”
In patients with superficial second degree burns, the doctors apply the fish skin and leave it until the patient scars naturally. For deep second degree burns, the tilapia bandages must be changed a few times over several weeks of treatment, but still far less often than the gauze with cream. Edmar Maciel said the tilapia treatment also cuts down healing time by up to several days and reduces the use of pain medication.
Antônio dos Santos, a fisherman, was offered the tilapia treatment as part of a clinical trial after he sustained burns to his entire right arm when a gas canister on his boat exploded. He said “After they put on the tilapia skin, it really relieved the pain. I thought it was really interesting that something like this could work.”
The initial batches of tilapia skin were studied and prepared by a team of researchers at the Federal University of Ceará. Lab technicians used various sterilising agents, then sent the skins for radiation in São Paulo to kill viruses, before packaging and refrigerating the skins. Once cleaned and treated, they can last for up to two years.
Tilapia skin is unlikely to be used in the US, where there is a substantial supply of donated human skin. Jeanne Lee said “I’m willing to use anything that might actually help a patient. It may be a good option depending on what country you’re talking about. But I also think the problem is that you need to find places that have the resources to actually process the skin and sterilize it, and make sure it doesn’t have diseases.”
In Brazil, in addition to the clinical trials, researchers are currently conducting histological studies that compare the composition of human, tilapia, pig, and frog skins. They are also conducting studies on the comparative costs of tilapia skin and conventional burn treatments. If clinical trials show continued success, doctors hope a company will process the skins on an industrial scale and sell it to the public health system.