Ringworm?

[AandJFishHouse]

Can fish be infected with ringworm? I’ve done as much googling as I can, and find only conflicting information. 
My next question: Is it possible that I was infected with ringworm from my fish tanks? 
 

 

[Janoš Bećar Pecaroš]

Ringworm is a fungal disease that is spread by contact and I’m pretty sure fish can get it. It thrives in heat and humidity, just like most fungus.

[AandJFishHouse]

Janoš, thanks for responding. Have you ever experienced this? My feeling is that it could transfer to my fish, and I’m really hoping for some responses from people who have dealt with this before. 

[Janoš Bećar Pecaroš]

I did not experienced this myself, hopefully never will. Ringworm is more prevalent in tropical regions. For example indigenous people of Amazonia have problems with this. Don’t hold you’re breath waiting for somebody that has experienced this. Ringworm is kinda like tuberculosis, it’s mostly eradicated but every know and than you hear of a case or a small outbreak.

[Flumpweesel]

I wouldn't expect it to be dangerous to your fish or that you got it from them.

It's generally transmitted skin to skin. Dogs and cats can catch it and pass it on to you (as can most mammals). 

I'd keep the infected area out the tank for your own sake keep the infection clean, dry and treat with over the counter anti fungal cream. Caught early should clear up quickly.

Try not to scratch it just makes things worse.

I've had it and it really isn't a major worry uncomfortable and unsightly it is easily caught from stray animals and people in contact with agricultural stock. It's not a very tough fungus and probably means you are a bit run down if you have it I think the stripping of our natural skin fauna by the necessary increase in the use of alco-rub during these interesting times will see an increase in this type of irritant's.  It is also only where you see it on that bit of your skin.

Its very similar to dealing with athlete's foot. 

Edited November 18, 2022 by Flumpweesel

[nabokovfan87]

Tagging in @Odd Duck!

The term you're looking for is zoonotic diseases.

I think it's an important thing for all hobbyists to know and learn about and is something that we honestly don't.  At least I know I don't.  Have gloves on hand as a part of your kit so that when you're treating something unknown, you can protect yourself and go ahead and do research.

[Odd Duck]

There are a couple fungal skin infections mentioned in the literature that can be gotten from fish but they are quite rare.  Most of the zoonotic diseases (diseases that can be transmitted from, or to, various animal species and humans) are from eating raw or undercooked fish, not from contact with fish.  Ringworm (dermatophytosis - a fungal infection of the skin) is most often contracted from contact with dried leaves.  The organisms that cause it are soil-borne organisms and always present, nearly everywhere in the world. It is unlikely that it will ever be eradicated since it is something that will likely always be present.  Most people get infected at some point in their childhood, then develop immunity and may never get infected as adults unless their immune system is suppressed for any of a variety of reasons.  There is evidence of increasing infection rates with certain fungal species in many areas and decreasing rates in other fungal species.

Once the organism starts growing in skin, it adapts and becomes better at growing in skin and becomes far more contagious.  This is when it starts transmitting between people, between people and animals, and between animals.  People in high risk professions (like veterinarians and technicians) will have higher risk of exposure to organisms that are already good at growing in skin.  Gardeners and those that work in the gardening/lawn care industry will have higher risk of exposure to less contagious/virulent strains.

I couldn’t find very much literature at all on zoonotic fungal infections from fish from a quick search but it can happen, with Sporotrichosis apparently the most common but still considered very rare affecting only 1-2 people per million (even more rarely from fish, far more likely to be from working with/in soil).  When it is from fish it’s usually in fishermen or those in the fish packing industry from fish induced injuries (fish spines, slips with contaminated knives, etc).  Dermatophytosis from the environment and pets is far more likely, affecting 20-25% of people worldwide.  Certain species of dermatophytosis is even a reportable disease in some countries.

So while fish can get fungal infections, and people can get fungal infections, they are rarely the same species causing those fungal infections.  In nearly all species, most fungal infections are opportunistic organisms causing infection in immune suppressed individuals.  The zoonotic dermatophytoses is an exception, but they are not typically caught from fish but from other humans or mammalian pets.

So, it’s not impossible to get a fungal infection from a fish, but it would be extremely unlikely to get one from our aquarium fish, likely exceedingly rare.

Edited November 18, 2022 by Odd Duck
Ugh, typos.