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Bacteria <hlth. concern> 1/31/13
Re: Lugol's Dip and Gorgonians, Pete, will you take a look at, refer? & bacteria f', human dis. -- 4/10/07 <Yowsa Pete! Thanks as usual for this dissertation! BobF> Dear Mark: Bob forwarded your email to me and asked me to lend a hand with your dilemma. It's very difficult to say what may have caused the demise of your H. kuda but I would be happy to share my thoughts on the matter with you for whatever it's worth, sir. Like all fish, seahorses do occasionally develop various granulomas, malignant neoplasms, tumors and fibrosarcomas associated with certain diseases or the aging process, but these primarily affect internal organs. Furthermore, such growths are not characteristic of vibriosis and, judging from the symptoms you described -- or lack thereof -- it seems unlikely that a Vibrio infection was involved in this case. I am more concerned about the possibility that the tumor may have been a granuloma symptomatic of a Mycobacterial infection. Granuloma disease is caused by gram positive, acid-fast bacteria from either the genus Mycobacteria or the closely related genus Nocardia invading the tissue and internal organs and organ systems. Both of these bacteria can affect the skin as well as the internal organs, causing nodules and granuloma. And both Mycobacteria and Nocardia can be transmitted to man, causing a localized, unsightly skin rash after entering through a cut or break in the skin. Here is an excerpt from my new book (Complete Guide to the Greater Seahorses in the Aquarium, TFH Publications, unpublished) that discusses mycobacteriosis in more detail, Mark. It may help give you a better idea whether or not the tumor you noticed could have been associated with granuloma disease: MYCOBACTERIOSIS, A.K.A. PISCINE TUBERCULOSIS Mycobacteriosis is also known by the following synonyms: fish tuberculosis, piscine tuberculosis, granuloma disease, swimming pool granuloma, fish tank granuloma, and acid-fast disease (Aukes, 2004; Leddo, 2002a). Like all fishes, seahorses are susceptible to Mycobacteriosis. It is not uncommon in wild-caught seahorses obtained from pet stores and is the second most commonly seen bacterial infection of syngnathids at large public aquaria after Vibriosis (Bull and Mitchell, 2002, p20). Cause: Fish tuberculosis is caused by pathogenic Mycobacteria, of which two different species are the primary culprits: Mycobacterium marinum and Mycobacterium fortuitum (Giwojna, Sep. 2003). Unlike most bacteria the plague fish, these Mycobacteria are gram-positive, and take the form of pleomorphic rods that are acid-fast and nonmotile (Aukes, 2004). When cultured on solid media, they form cream-colored to yellowish colonies (Aukes, 2004). Mycobacteriosis is worldwide in distribution (Giwojna, Sep. 2003). All fish species are considered susceptible to it (Aukes, 2004). Although this disease can in fact infect almost all fish, certain species are more vulnerable than others (Giwojna, Sep. 2003). The most susceptible species are freshwater tropicals such as black mollies, all gouramis, Neons and other tetras, all labyrinth air breathers, and most species of the Carp family (goldfish and koi, for example), Aukes, 2004. Mycobacteria are ubiquitous and waterborne, and the aquatic environment is considered the disease reservoir for fish tuberculosis (Aukes, 2004). Mycobacterium marinum has been cultured throughout the world from swimming pools, beaches, natural streams, estuaries, lakes, tropical fish tanks, city tap water and well water (Aukes, 2004; Leddo, 2002a). Human epidemics of granulomatous skin disease have occurred from swimming in infected water, and in fact, this mode of human infection is far more common than infection from exposure to infected fish tanks (Aukes, 2004; Giwojna, Sep. 2003). Clinical Signs: There is a very severe or peracute form of this disease, in which fish can simply be found dead without showing any telltale signs or symptoms (Bull and Mitchell, 2002, p20), but that is quite rare. In my experience, Mycobacteriosis is a chronic disease that progresses quite slowly in aquarium fishes (Giwojna, Sep. 2003). It may take years for an infected fish to develop any symptoms of apparent illness and much longer before it becomes fatal (Aukes, 2004). The glacial progression of the disease makes it difficult to diagnose. Some early signs to look out for include lethargy, fin loss, emaciation, skin inflammation and ulceration, edema, Popeye, and peritonitis (Aukes, 2004). There may be superficial skin lesions that take the form of small subdermal lumps or pus-filled nodules of granulation tissue (Bull and Mitchell, 2002, p21). These are simply the outward manifestations of a systemic infection that may already involve many of the major internal organs (Bull and Mitchell, 2002, p21). In later stages, nodules may develop in muscles or skeletal structure and deform the fish. (Giwojna, Sep. 2003). As difficult as slow-moving TB may be to diagnose while the infected fish is alive, once the victim expires, postmortem examination will reveal clear, unmistakable signs of Mycobacteriosis (Giwojna, Sep. 2003). The telltale granulomas will appear as gray or white nodules in the liver, kidney, heart and/or spleen (Aukes, 2004). There is often black, necrotic tissue eating away at the internal organs, and there may also be skeletal deformities. Diagnosis is then confirmed by the presence of acid fast bacteria in tissue sections (Giwojna, Sep. 2003). Treatment and Control: There is no practical method for treating mycobacteriosis or granuloma disease at the hobbyist level. As discussed below, good aquarium management can prevent Mycobacteria/Nocardia from becoming problematic. Prevention is the watchword for this condition. Transmission: The bacteria can be transmitted through the water from open ulcers, through contaminated food (including live foods such as shrimp or molly fry), via feces of infected fish, or through the consumption of infected, dead or dying fish in the tank (although the latter does not apply to seahorses), Aukes, 2004. Contributing factors: This disease is not highly contagious and does not seem to spread from fish to fish readily (Aukes, 2004). However, fish TB it is often associated with poorly kept or dirty tanks with poor water quality (Aukes, 2004). Chronic stress from factors such as overcrowding, malnutrition, or aggressive tankmates often plays a role as well (Giwojna, Sep. 2003). Mycobacterium, the causative organism, is believed to be ubiquitously present, making it very difficult to eliminate it entirely. However, if good aquarium maintenance and management is followed, including vacuuming of the gravel along with good filtration and regular water changes, combined with a nutritious diet and the addition of an enrichment product rich in vitamins, the problem can be minimized and eliminated as a cause of mortality (Aukes, 2004). Any dead fish should quickly be removed and disposed of properly. Diseased live fish should be isolated and treated in a hospital tank (Giwojna, Sep. 2003). Transmission to Man: The seahorse keeper should be aware that piscine tuberculosis is one of the few forms of fish disease that is communicable to humans (Leddo, 2002a). This transmission usually manifests itself as an unsightly skin rash involving one or more granulomas on the arms of the fish-keeper (Leddo, 2002a). In severe cases, these nodules of inflamed tissue can become large and disfiguring. They can spread and be very difficult to eliminate. The granulomas often take some 2-4 weeks after exposure before manifesting themselves, so the individual is frequently unaware of how he or she contracted them and the condition very often goes undiagnosed (Giwojna, Sep. 2003). The Mycobacteria that cause the disease typically gain entry through a break in the skin such as a cut, scrape, or abrasion on the hand or arm of the aquarist (Leddo, 2002a). Although unsightly, the granulomas themselves are not a serious problem and are almost always localized and most certainly curable in healthy individuals. But for those of us whose immune systems are compromised by AIDS, kidney disease, diabetes, liver dysfunction, chemotherapy or the like, the infection can sometimes become systemic or, on rare occasions, even life threatening (Giwojna, Sep. 2003). Awareness is the appropriate response to the risk posed by fish tuberculosis. The seahorse keeper should be aware of the remote possibility of being exposed to Mycobacteria via his aquarium, and take appropriate precautions, but there is certainly no need to be overly concerned (Giwojna, Sep. 2003). The aquarist should merely remain aware of Mycobacteria and follow the usual sensible precautions. Nets, aquarium accessories and equipment, and any other items that may come in contact with the fish should be sterilized between uses to prevent cross-contamination (Giwojna, Sep. 2003). Avoid mouth-siphoning of the water in a Myco-positive tank (use a hand pump instead). Mycobacterium cannot penetrate intact skin -- it only causes infection after entering through open wounds or source, so make full use of aquarium gloves and don't place your hands or arms in the aquarium if you have any cuts or scrapes (Giwojna, Sep. 2003). Handle sick fish carefully, dispose of deceased specimens properly, and scrub up afterwards. Do NOT dispose of dead fish by flushing them down the toilet, as this is a prime way to spread disease. Place the fish carcass in a plastic bag or wrap it in some foil and dispose of it with the solid waste of the household. And don't feed dying fish to larger carnivorous fish, since this an excellent way to spread infection (Giwojna, Sep. 2003). One thing hobbyists who are worried about fish TB can do to allay their concerns is to get their seahorses and live foods (crustaceans such as shrimp are known vectors for Mycobacteriosis) from a High Health facility such as Ocean Rider rather than from their local fish store (Giwojna, Sep. 2003). Seahorses at OR are routinely screened for pathogens and parasites by independent examiners from an outside agency (DVMs with the Department of Agriculture), and I know for a fact that Mycobacteriosis is one of the diseases they specifically check for (Giwojna, Sep. 2003). Thus far, multi-organ histopathology has found no granulomas and tissue sections have revealed no acid-fast bacteria -- conclusive proof that Ocean Riders are free of Mycobacteria. <Close quote> That's the rundown on mycobacteriosis or granuloma disease, Mark. The very similar Nocardia is a gram positive, acid-fast, filamentous bacteria and is even more insidious than Myco. Nocardia is closely related to the Mycobacteria that cause piscine TB or granuloma disease and, like Mycobacteria, it can affect the skin as well as the internal organs, causing nodules, granulomas and pyogranulatomous cysts. And like Mycobacteria, Nocardia can be transmitted to man, so be sure to take appropriate precautions if you suspect granuloma disease may have caused the death of your H. kuda. Here is some information from Paul Anderson explaining how professional aquarists typically deal with Mycobacterium/Nocardia: Fellow Seahorse Enthusiasts: Mycobacterium is a genus of bacteria that are ubiquitous in almost all environments. Mycobacterium infections occur in many (if not all) vertebrate taxa (e.g., mammals, birds, fish, etc.). Some studies that have looked at prevalence of infection of Mycobacterium in wild animals have often found that a small percentage of wild animals are infected, even without clinical signs. The most common Mycobacterium species found in seahorses are M. marinum, M. chelonae, and M. fortuitum. There is currently no cure for mycobacterium infections in fish. The options available are to 1) depopulate and disinfect the system, or 2) maintain the fish but prevent cross-contamination by observing strict biosecurity protocols. The second option is often chosen by public aquaria with long-standing displays, when aquaculture/production of the infected fish is not an issue. Many mycobacterium spp. can cause disease in humans, especially if the species is a rapidly growing one and/or if the person is immunocompromised. Of the three species mentioned above, M. marinum is a slow grower, and grows at 25 degrees Celsius incubation, but not at 37 degrees Celsius. The other two are rapid-growing species and grow at both temperatures of incubation. The significance of 37 degrees is that it is human body temperature. While most infections of otherwise healthy people are limited to lesions on the extremities (even with infection by a rapid-grower), there is a greater risk of the rapid-growers to cause systemic disease (especially in immunocompromised people). In a Myco-positive tank, the best option is not to come in contact with water or fish; wear gloves (sleeved gloves if necessary). Avoid mouth siphoning (use a hand pump). Having said that, in an aquarium situation mycobacterium only causes infection if it enters a wound; it cannot penetrate intact skin. Effective disinfectants against mycobacterium include spraying with 70% Ethanol and allowing the equipment to air-dry, and bleach baths (I use 50ppm bleach baths with a minimum contact time of one hour, this has been reported to be effective against M. marinum) followed by sodium thiosulfate neutralization baths. Ultraviolet light sterilization is also recommended in Myco-positive systems. If you've got Myco-positive tanks among other systems, common sense suggests performing husbandry on these systems last in your rounds. A note on ethanol: I have found in my experience that seahorses are very sensitive to ethanol, so I advise being very cautious to avoid overspray into tanks (while we're'¬"¢re on the topic, has anybody else observed this?) Check out the following for more information about mycobacterium infections in fish/aquaria: <_ http://edis.ifas.ufl.edu/VM055_ (http://edis.ifas.ufl.edu/VM055) > <_ http://www.mdsg.umd.edu/Extension/finfish/FF9.html_ ( http://www.mdsg.umd.edu/Extension/finfish/FF9.html) > Mainous, M.E., and S.A. Smith. 2005. Efficacy of common disinfectants against Mycobacterium marinum. Journal of Aquatic Animal Health 17: 284-288. Paul Anderson Ph.D. Candidate Department of Fisheries and Aquatic Sciences University of Florida That's the situation when Mycobacteria is confirmed in an aquarium, Mark. As long as you observe the proper precautions and practice good aquarium management, it's a problem the aquarist can sometimes live with... Nocardia is a different matter. When Nocardia is confirmed in an aquarium, the only real recourse is to break down the entire aquarium, discard the live rock, substrate, and invertebrates, sterilize everything, and start over from scratch. The problem is that Nocardia is saprophytic -- it doesn't require a host to survive and it will persist in your system indefinitely. These bacteria live off any kind of dead or decaying organic matter; in nature they are commonly found in soil and wastewater -- in your tank, Mark, they are no doubt entrenched in your substrate, live rock, filters, everything -- where they act as a disease reservoir, ready to infect any new fish and invertebrates (or careless humans) they encounter when the opportunity presents itself. The risk of cross-contamination of your other tanks and specimens is great, compounded by the fact that human health (primarily yours, Mark) is also at risk from this organism. If your H. kuda was infected with Nocardia, then everything in your 25-gallon aquarium has been exposed to these bacteria and is potentially a source of infection. Leading the tank lay fallow indefinitely will not help with Nocardia whatsoever. If Nocardia killed your kuda, you must consider all the equipment, decor and specimens in the tank to be contaminated, Mark -- treat them like you would toxic waste or any other biohazard. Even your invertebrates are a risk. Your coral, macroalgae, etc,. are all sources of organic matter, and can therefore harbor Nocardia and carry the infection. Do NOT disperse your live rock, substratum, Gorgonia and soft corals, macroalgae, equipment or accessories from the 25-gallon tank to your other aquaria, Mark, or you will be inoculating them with Nocardia and spreading the infection to all your tanks! And you must be extremely careful to avoid accidentally cross-contaminating your other tanks from your 25 gallon aquarium. Any nets, hydrometers, or other equipment used in your 25-gallon aquarium should be sterilized after every use and not placed into or used in any other tanks. Avoid working in infected aquarium with your bare hands, scrub/disinfect your hands and arms thoroughly after working on the tank, and do not place your hands in the 25-gallon tank and then place your hands in another aquarium. These bacteria can even be transferred from one aquarium to another by splashing water droplets or as an aerosol via the mist generated from a protein skimmer or an airstone. Be careful! That is what I typically advise hobbyists when Nocardia has been confirmed in their aquaria, Mark. I hesitate to recommend such drastic measures when Nocardia or Mycobacterium have not been confirmed. And the tumor that you described is not typical of the pyogranulatomous cysts that characterize Nocardia. They most often present as greyish-white pimple like lesions on the skin. They are often motile when manipulated and may release a cheesy exudate when compressed. That does not sound like the hard mass you detected beneath the skin near the vent of the H. kuda. So you're going to need to use your own judgment, Mark. To be 100% safe, you could discard the contents of your 25-gallon aquarium, sterilize everything, and start over from scratch. Or you could dip the live rock, Gorgonia, and corals with Lugol's solution as a precaution and then trust to good aquarium management to keep the seahorses in your 40-gallon aquarium healthy and happy. Since Mycobacteria and Vibrio bacteria are virtually ubiquitous, and normally only become problematic when the seahorses have been stressed and their immune systems have been impaired, I might be inclined to take the latter course in your case. If you can provide your seahorses with optimal water quality, a nutritious diet, and they stress-free environment, the chances are good that your livestock will not be affected by granuloma disease or vibriosis. Starting out with seahorses from a high-health aquaculture facility that you obtain directly from the breeder will further increase your chances for success. As an added precaution, you may also want to consider installing an ultraviolet sterilizer on your 40-gallon seahorse tank after it has cycled completely and the biofiltration is well-established. Best of luck with your new seahorse tank no matter how you decide to proceed, Mark! Respectfully, Pete Giwojna, Ocean Rider Tech-Support Re: Lugol's Dip and Gorgonians, Pete, will you take a look at, refer? -- 4/10/07 Dear Bob: <Pete!> I'm always happy to help when I can, sir. <And you do a fine job of it, I assure you> When I receive inquiries from aquarists regarding Mycobacteria/Nocardia, I feel it is very important to provide them with as much information as possible because of the possibility of human transmission and because they may be confronted with the decision as to whether or not it's necessary to depopulate their aquarium, sterilize everything, and start over from scratch. So I make it a point to try to arm them with all the facts they need to make an informed decision in that regard. <Yes... and one of the principal reasons for my encouraging the publication of your book, your articles (as well as others... including my own!) to get "complete answers" to folks... in a speedily manner> Hopefully, once we get my new book on seahorses published and into the hands of the hobbyists, there won't be a need for us to devote so much time discussing these issues on the forums. <Heeeeee! You'll see...> Happy Trails! Pete Giwojna <And to you, Bob Fenner, out in HI, at times visiting with Carol and Craig and their (now four year old!!!) boys, Dylan and Cooper>
- Fish TB - Please help <I can try... JasonC here at your service.> I seem to have run out of ideas. My Perc has developed what appears to be a swelling mainly on the left half of his body. He does not use his tail to swim, just his pectorals and there has been a colour change to the rear half of his body (appears grayish under the skin). I thought it may be a swim bladder infection as he swims nose down and spends most of his time vertical with his head buried in a large mushroom polyp. I have checked the water quality in my 70 gal live rock tank and it remains good. <Do you have any venomous tank residents like Rabbitfish?> The only other thing that I have been told is that it could be TB and that it could spread to the other residents, is this true and if so how can I avoid disaster? <Egads...TB would be a severe diagnosis. I had to go research this a bit because I've never encountered it before. The consensus seems to be mycobacteriosis, for which there is no treatment. The data also shows that mycobacteriosis is also contagious so you should at the very least isolate this fish in a quarantine tank to insure the problem isn't transmitted. You may want to consider sterilizing the system that the fish is in now... again, if mycobacteriosis is in fact the culprit.> Tigga is 4 years old, he was always active and always the greedy one, he is the biggest character in my tank, I should hate to loose him. <I'm sorry to be the bearer of bad news, but it would seem you knew this would probably be the case. Here is a link I found on the net that should provide some background: http://members.optushome.com.au/chelmon/Myco.htm > Please help. Regards Dean <Again, I'm very sorry about this. At this point, if you want to end things kindly, put the fish in a small container with some water, and freeze it. Cheers, J -- > Bacteria Infection Questions ( possible solution? ) Bob, Thanks for your reply. I have been using a "Red sea" PH tester and have check my tank once a week, in which it reads at 8.2 - 8.4. I decided to switch to a "tetra" ph tester, and this one would read 8.0. This test was done towards the end of the light cycle, so I expected it to be a bit higher. With this in mind I decided to check the Alk, and it was at or close to nothing. <As I suspected> I then added a small amount of extra buffer to my top-off jug, and let my doser add it over night. The next day my French has came back very well. Swimming & eating well, but still had cloudy eyes just a bit. <This will clear in time> I am hoping to have this problem now resolved. Do you agree that this brought on the behavior? <Likely so> How long roughly should it take till his eyes clear up? <Probably a few weeks> All and all, I did learn that even with a 32 gal. 1 - 2 week old buffered water change pre-mix , and a change of 8% weekly, you still need to supplement with additional buffer ! Any other thoughts would be appreciated. Thanks - D. Mack <Bob Fenner> The Chromis Were the Culprits? >Hi, Marina. >>Hello Barb. I hope everything is going well for you. >I've got another question for you relating to the bacterial infection that ravaged through my Coral Beauty. Since she never showed any effects of the infection until I added the 6 green Chromis to the QT, what are the chances that they are carriers of the infection, even if they themselves don't show any signs of infection (I've had them for over 5 weeks and the owner of the LFS said she had them for 2 months)? Is that possible? My greatest fear is that, after a 30-day quarantine (post CB death), I transfer these seemingly healthy fish to my main tank only to have my other fish doomed by whatever they might be carrying. Barb >>I thought for sure we'd covered this last week.. either that, or this is a serious case of deja vu! In any event, at this point, even IF the Chromis were the culprits, I doubt that whatever bacteria that *were* present are still present. Between their own immune systems and your treatments, the infectious agent(s) wouldn't stand much of a chance. Marina Dealing With A Bacterial Infection? If in fact the butterfly died from a bacterial infection, what should I do at this point? Will it remain in the water and spread to other fish? Thanks again, James <Well, it's tough to say. It would certainly be prudent to consider all tankmates "exposed" to the infection, and observe them cautiously for potential signs of infection. Unlike some of the more aggressive parasitic diseases, like ich or velvet, you can probably get away with some close observation of the remaining fish, taking action if you deem it necessary, as opposed to removing the fishes and running the tank "fallow"...Action would include feeding medicated foods to the fish, or removing them to a dedicated "hospital" tank for treatment. Either way, the key is observing the fishes closely, and taking decisive action if it is needed. Good luck! Regards, Scott F> Flesh eating bacteria??? 8/9/05 The other day, I noticed what looked like a fin nip on my pyramid angel (didn't pay too much mind but watched to see who the culprit was). I went to work and when I came home, I noticed the area was almost 3x the size of the "nipped" area and the fish was panting heavily. Over the next 4-6 hours, I could literally watch the area become grey and fleshy and disintegrate away right in front of my eyes. I put the fish in quarantine where it died about 1 hour later. What in the world did I witness? <A rapid necrosis caused by...?> Today I noticed the Red Sea Chevron had it too and I immediately removed him but within hours, the area was 3-4 times the size and once again grey and fleshy and I know that within the next few hours he will be gone also. Both fish came from the same store and were purchased together but now I need to know what I'm up against so I do not lose my whole tank. Please help!!! Thanks, Jeffrey <... very frightening... but it reads like a super-aggressive infection of Mycobacterium marinum, or other bacteria... I would definitely not put your hands in the tank w/o using waterproof gloves... and would try weakening the pathogen by lowering your specific gravity (quickly if you only have fish livestock). You might want to save, bring a freshly dead specimen to a veterinarian that specializes in such diseases, fishes... or a college for examination. BobF> Vibrio I have looked all over your site, and cannot find a definition for "Vibrio". Can you hook me up with a link? Kasey DeVita <Mmm, another "as-yet-to-be-done" (of many) parts of the WWM sites... Here's a link to links on this bacteria genus and aquariums: Vibrio Googled. Can be a "nasty customer"... but almost always a secondary, tertiary trouble... from other root causes. Bob Fenner>
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