Please explain "Immunity" in regards to ich

[Savant]

I have been seeing people mentioning their fish have built an immunity to ich and other parasites.

Im curious as how does something develop immunity to a parasite? I can understand resistance to parasites through something like a well developed slime coat, but immunity? Does the fish's body develop some sort of active defense specifically against a parasite through repetitive exposure? And if the fish is truly immune does the ich parasite die do to a lack of a host thus clearing the tank after 12 weeks?

I am confused by this and hope somebody can clarify. Thanks

 

[rwb500]

fish have adaptive immune systems, like people do. i am not sure if there is any evidence proving that fish can become immune to ich, but it is theoretically possible, especially in a closed environment without any new strains coming in.

 

[MondoBongo]

one of the big things to note, is that not all fish are created equal in regards to their immune response, and not all fish have been comprehensively studied for their immunity to these parasites.

also generally noted as the immunity being transient, in some things i've read lasting up to 6 months.

some of these links from the following post have some of this information in them:

http://reefcentral.com/forums/showpost.php?p=23523035&postcount=86

summarized in the following:

http://www.google.com/url?sa=t&rct=...3mKIAwmVSB8_5ZM1A&sig2=0x_iWisyU76DZmjzWOwAeA

A certain degree of resistance to C. irritans invasion was observed in fish that had survived several infections.

Fish susceptibility. Different species of fish showed different susceptibility to Cryptocaryon imitans infections. While Pernpheris vanicolensis and Sparus aurata juveniles were readily infected and usually died within 1 or 2 wk, Mugil cephalus, Oreochromis rnossambicus and Abudefduf saxatilis, which were kept in the same infected tank, s u ~ v e dse veral waves of tomite attacks after which they apparently acquired immunity, sustaining little or no infection for several months. S. aurata larvae as young as 3 wk could be infected.

http://www.sciencedirect.com/science/article/pii/S1050464885700435

Acquired protection toCryptocaryon irritanshas been demonstrated for the first time, using the grey mullet,Chelon labrosus, as an experimental host. Fish, immunized by controlled infections, established immunity against challenge infections withC. irritans, the degree of protection correlating with both intensity and exposure levels, with relatively few fish developing full protection. Protection lasted for six months in the absence of re-exposure to the parasite. There was no evidence of cross-protection in mullet against infection with the closely related fish parasite,Ichthyophthirius multifiliis.

http://reefkeeping.com/issues/2003-10/sp/feature/index.htm

Fish can develop immunity to Cryptocaryon irritans that can last for up to six months (Colorni, 1987 and Colorni & Burgess, 1997).

http://edis.ifas.ufl.edu/fa164

As is seen with other diseases, general fish health and environmental factors including water quality will affect the status of the fish's immune system and may worsen the effects of an infection. If the immune status of the fish is compromised or if environmental factors are less than optimal, Cryptocaryon infection will be even more explosive and harmful.

Fish that survive a Cryptocaryon infection develop immunity, which can prevent significant disease for up to 6 months (Burgess 1992; Burgess and Matthews 1995). However, these survivors may act as carriers and provide a reservoir for future outbreaks (Colorni and Burgess 1997).

More targeted development of a vaccine to protect against Cryptocaryon irritans has been ongoing for a number of years (Yambot and Song 2006; Hatanaka 2007; Luo et al. 2007; Bai et al. 2008), and preliminary results are encouraging. However, vaccine development is a lengthy process, and no commercial vaccines are currently available.

 

[MondoBongo]

for some weird reason some of the text i copied and pasted from the PDF files got all munged up. not sure why, but if you go to the original PDF's it should ready just fine.

most of these things i've found don't have strict details on how the immune response works though.

i was able to find a pretty deep in to the parasite, but haven't had a chance to read it all yet:

http://www.google.com/url?sa=t&rct=...qXyxZohIQOCKdRTiw&sig2=YozcWKcER7zLjIx2DQb6Lg

if the above link doesn't have it, you might be best served to try to find original paper most of the other articles are citing:

Cryptocaryon irritans Brown 1951, the cause of ‘white spot disease’ in marine fish: an update - Colorni, 1987 and Colorni & Burgess, 1997

here is the link to buy it, but i can't find it for free. curse the academic pay wall!

http://link.springer.com/article/10.1023/A:1018360323287

 

[Dmorty217]

Its only a short term immunity, add any new fish and watch the outbreak happen again

 

[3FordFamily]

I post about this frequently. Rather than reiterating it search my posts. My fish don't sucomb to ich only new additions can and occasionally do. All the resident fish show no signs due to repeated introduction of parasites in to my system as a result of no qt procedure. I am able to successfully keep fish that many cannot even with proper qt and treatment procedures. I can't pretend to know exactly why but I see it akin to how antibacterial soaps have led to super bacterias and frequent infections because it suppresses immune responses (lack of exposure).

Another somewhat relevant analogy would be that of vaccines. Fish not exposed to the parasite for long periods (not vaccinated per se) are much more likely to succomb

 

[Savant]

Thanks for the info! I wish my dog would develop immunity to fleas but I doubt I could survive the repeated infection process...lol

 

[3FordFamily]

Interestingly some wild dogs build up somewhat of an immunity. You can catch ten strays from the same "pack" and some of the individuals, generally older or middle aged (but not very old) have few fleas while others are infested from head to toe.

Witnessed this a lot when ln I worked in veterinary care. Same with mites, mange, and other pests.

And unlike dogs, fish can develop a thicker slime coat as a shield which helps further.

 

[ca1ore]

Mondo referenced the available research. Everything else is simply anecdotes, speculation, hobbyist observations or unsubstantiated opinion. I don't necessarily doubt folks experiences, but there is no scientific bases for many of the conclusions. For example, I have wondered to myself whether a fish that is infected with ich doesn't simply develop a thicker slime coat, thus preventing reinfection. Not an 'immune' system response, per see, but potentially quite effective. Also speculation!

 

[3FordFamily]

There are plenty of scientific research studies that show similar results in similar circumstances. One thing many people don't understand (aside from rudimentary scientific process logic and rudimentary statistics) is that correlation does not equal causation. Science can provide narrow answers only as suggestions. There are too many other factors and unknown (and untested) factors that render much of it useless at best. To say that x causes y because in this experiment (many aren't true experiments rather quasi experiments or pre experiments) x happened and then y followed. Even if it is reliable (ie repeated tests show similar or the same results) it is still not valid.

As an example, if you're at a shooting range and you aim for the bullseye and shoot top left each time, that's a reliable result but not necessarily valid.

Extraneous factors are inherent in literally every single scientific study. When different research is conducted with actual experiments (not to be confused with quasi and pre experiments which are moderately implicit at best) in various ways, that can cover the hundreds of exterraneous other independent variables that can affect the dependent variable, that's when causality may be more strongly linked to correlation.

I argue that results speak louder than any research. My 11 years experience and 3-7 tanks at a time is purely anecdotal and a poor sample size from which to draw inferences about the population of those who do what I do. However, many seasonsed veterans do it as well successfully.

Rather than scientifically prove what I believe works (and have irrefutable evidence to support in the form of my current and past successes that can be confirmed by anyone at any point in time), I choose to operate logically, reading the science and taking it all with a grain of salt. Much can be learned from scientific research, it helps explain reality one small fragment at a time.

So many things appear true on paper but in practice fail epically. Socialism is a great example. On paper it's fantastic. However, exterraneous factors such as human psychology render it impossible to create the socialist utopia possible on paper.

 

[MondoBongo]

There are plenty of scientific research studies that show similar results in similar circumstances.

please cite references then, and stop presenting conjecture.

I argue that results speak louder than any research.

this is laughable.

 

[MondoBongo]

So many things appear true on paper but in practice fail epically. Socialism is a great example. On paper it's fantastic. However, exterraneous factors such as human psychology render it impossible to create the socialist utopia possible on paper.

this is the absolute height of false dichotomy, and has nothing to do with the current argument.

this has no bearing on controlled scientific study, provable, and repeatable results.

if we operated strictly off of anecdotal evidence or what people "think" happens we would still believe the earth was flat and that "bad air" and "bad humors" caused disease.

 

[Paul B]

Does the fish's body develop some sort of active defense specifically against a parasite through repetitive exposure? And if the fish is truly immune does the ich parasite die do to a lack of a host thus clearing the tank after 12 weeks?

I generally do not post on ich threads because of all the arguments that will follow, but I will say this. Fish do become immune from parasites and almost everything else. Some of my fish are over 24 years old and have never had any parasites in their 43 year old tank. All of my fish are immune (and they are almost all spawning) as I can take any fish, from anywhere, even the sea and put it in my reef with no worry about parasites. I have been doing this for about 35 years after I learned how to get fish in the condition to become immune. I am presently writing a book and this is in it. I have posted this numerous times but won't go into it any more on here because of what I already said. Good luck and have a great day.
:bum:

 

[Pastey]

I sort of view ich as a secondary infection. If a fish's health is less than ideal, it lacks the "energy" to fight off the infection and succumbs to it. If a fish is well fed and eats proper nutrition, their immune system can overcome. I know ich is a parasite and not an infection...I'm just making a correlation.

 

[3FordFamily]

please cite references then, and stop presenting conjecture.



this is laughable.

Mondo, you must have missed the negation of references that are often cited and the rudimentary explanation of how one should not draw inferences based on them, for the most part. I will reiterate, correlation does not equate causality.

this is the absolute height of false dichotomy, and has nothing to do with the current argument.

this has no bearing on controlled scientific study, provable, and repeatable results.

if we operated strictly off of anecdotal evidence or what people "think" happens we would still believe the earth was flat and that "bad air" and "bad humors" caused disease.

You misused the term "dichotomy" as none was presented by any stretch of the imagination.

The very nature of analogies are that they're not generally directly relevant to the discussion at hand, hence the term "analogy".

And the purpose of my post you read poorly, apparently, was to point out the inherent fallacies of logic, scientific method, statistical significance, and experiment processes. I was suggesting that perhaps my (admittedly) anecdotal evidence was just as useless as many "research" studies due to the aforementioned issues.

I painted the door of my business red. In march, sales were 120k. I repainted the door in april. In may, sales were 180k. The red door must have increased sales.

Unfortunately, because we know so little of marine biology, this ANALOGY (again, not directly relevant to the discussion point) explains how drawing inferences on so many research experiment outcomes is often a fallacy. There are an exorbitant amount of extraneous factors that could have affected the dependent variable being tested.

 

[3FordFamily]

I generally do not post on ich threads because of all the arguments that will follow, but I will say this. Fish do become immune from parasites and almost everything else. Some of my fish are over 24 years old and have never had any parasites in their 43 year old tank. All of my fish are immune (and they are almost all spawning) as I can take any fish, from anywhere, even the sea and put it in my reef with no worry about parasites. I have been doing this for about 35 years after I learned how to get fish in the condition to become immune. I am presently writing a book and this is in it. I have posted this numerous times but won't go into it any more on here because of what I already said. Good luck and have a great day.
:bum:

Same here but your experience dwarfs mine. I have put fish noticeably covered in ich in to my systems to help them heal. My fish little to no signs and certainly do not succumb. I do this because my water parameters and the conditions of my reefs are conducive to the healing of the fish. I also feed well, a variety of foods, soaked in selcon and garlic. I do not believe that garlic cures ich, but I do believe it can be linked to better immune response and most important it certainly increases appetite. A fish that is eating many calories per day is more likely to kick a parasite. Anything I can do to increase nutrition is a win/win for the fish.

I would love to hear more from you, and read your book. Please let me know when it is published.

I sort of view ich as a secondary infection. If a fish's health is less than ideal, it lacks the "energy" to fight off the infection and succumbs to it. If a fish is well fed and eats proper nutrition, their immune system can overcome. I know ich is a parasite and not an infection...I'm just making a correlation.

I largely concur, there are certain fish that are too weak to fight off the parasite. Again, so many factors could lead to this but I think ich is the catalyst for the destruction of the fish rather than the cause, as you say. To put it another way, it's a symptom but not the root cause or disease.

 

[3FordFamily]

I also have no way to quantify or prove this, but I suspect that stress is a more deadly factor to parasite-related death in marine fish than is the presence of the parasite in the fish's ecosystem.

I have stressed fish out in the past with QT procedures and still lost them. For a fish collected from the reef, going in to a tank with PVC pipe as structure, a beneficial bacteria population insufficient to support the fish's bioload (and thus requiring frequent water changes) is hardly natural or conducive to low stress levels.

Water changes cause stress because even if the water is pre-mixed, pre dosed, pre-heated, it is still not identical to the water in the system currently (which is why you're removing the old water, you want to improve it). The act of water changes themselves are very stressful for the fish during the initial phase.

I do not QT, but I also do not do water changes for at least a month following an addition that is likely to be easily stressed or is more commonly affected by parasites. (IE many tangs, angels, hard to keep wrasses, etc.). My fish are left alone less feeding procedures for the first month to adapt and relax.

HOWEVER, if your tank is full of aggressive fish who will bully a new addition, a QT may be a LESS stressful endeavor. In my case, I spread aggression with multiple angels, multiple tangs, multiple wrasses, etc and add more than one at a time to reduce aggression. I've never had a fish die from being bullied, surprisingly but I do have a hospital tank handy in case this does happen.

 

[shermanator]

I'm curious... are the arguments that this "immunity" is innate or acquired?

If it's acquired, how would that work? I mean, fish have immune systems like we do and they are not equipped to acquire immunity to parasites (nor are we). If immunity to parasites was possible on a reasonable time scale, there would be no TB (or many other tropical diseases) -- or at the very least we would have vaccines against TB.

I would believe that some fish have innate immunity (not a species of fish, but individual fish and their off-spring). But the idea that animals can acquire immunity to parasites is not consistent with basic immunology.

In reading this thread, I am not sure whether the pro-immunity side wants to consider peer-reviewed science, but here is a good general review on immune systems and the difficulty in acquiring immunity to parasites: http://www.nature.com/nri/journal/v10/n2/full/nri2673.html (this isn't about Ich in general, but it does cover dinoflagellates and Ich is a dino).

 

[3FordFamily]

One more tidbit to think about -- Pay attention to who funds research. I didn't even TOUCH bias but it's a HUGE concern. Many "studies" are conducted with an agenda.

Not saying this is the case, but don't you think a study conducted or funded by Kent Marine, Cupramine, or any company offering products to "cure" ich might skew results?

Anyone remember the "Study" that "proved" that vaccinations cause autism? When in reality, we have increased our knowledge of the spectrum over time so what seems like an increase in autism occurrence is actually an increase in the amount of diagnosis. The spectrum is much better understood now and things like Aspberger's syndrome were completely unknown to exist let alone be on the autism spectrum.

Heck when many of us were kids, you could go to school with black eyes and no one said a word. Health checks were far less exhaustive, same with psych evaluations. We now hyperfocus on many aspects of our children's lives. Mostly for the good, but some would say it's a bit excessive.

 

[shermanator]

I generally do not post on ich threads because of all the arguments that will follow, but I will say this. Fish do become immune from parasites and almost everything else. Some of my fish are over 24 years old and have never had any parasites in their 43 year old tank.

Do you really mean immunity? Or do you mean asymptomatic? There is a huge difference from a science perspective, and from a tank-observer-perspective there is no difference in appearance.