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Author: Dr. Adrian Lawler  
Title:  Some Infection Details of Aquatic/Fish Tank Infections
Summary: Since the posting of his talk, "Diseases Transmitted to Humans," a number of people have contacted Dr. Lawler concerning their own experiences with water borne infections. Infection methods of some of the cases are presented here.

Contact for editing purposes:
email: Adrian Lawler <>

Date first published: March  2004
Publication: Original to Aquarticles. Not previously published
Reprinted from Aquarticles:
May 2004: Posted by Roland Seah on his web site in Singapore:
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Dr. Adrian Lawler,
P.O. Box 48,
Ocean Springs.
MS 39566
#205 - 5525 West Boulevard
Vancouver, British Columbia
V6M 3W6

Some Infection Details of Aquatic/Fish Tank Infections

by Adrian Lawler, Ph.D.
(retired) Aquarium Supervisor (l984-l998) J. L. Scott Aquarium Biloxi, Ms 39530

Since the posting of my talk in l997, various people have contacted me concerning their water-borne infections. As details of the methods of infection may benefit the reader, I have summarized some of the cases reported to me and presented them herein. Names, and cities, of people infected are not included to protect privacy. For brevity, each type of disease is listed, then the infection methods of some of the cases are presented.

Treatment methods and final outcomes are not included for each case. People suspecting an infection should consult their own medical doctors for diagnosis and treatment. In Tank Safety/Fish TB, (as posted on Aquarticles), I list steps to follow to seek a cure of an infection.

Mycobacterium marinum (either diagnosed or strongly suspected):

1….Female got pinched on right index finger by a blue crab. Infection resulted in pinch site that did not bleed. Lump formed at pinch site. It took a long time to diagnose correctly and infection had become more intense, so it took long time, over a year, to cure.

2….Male public aquarium worker was stuck by sheepshead spine on right small finger. Within 2 weeks finger had become swollen, felt hard, and was dark purple in color. A sample was cultured, M. marinum was diagnosed; infection was cured in 6 months.

3….Male was stuck in left middle finger by fin spine of hybrid striped bass in an aquaculture facility. Shortly after being stuck, the finger became swollen and pink with a 3-inch pink streak going toward palm of hand, and an open wound at site of infection. After initial cure, the worker was infected twice more at facility, once by a splinter from handle of fish net.

4….A middle-aged female cut her finger on a glass rock while cleaning her fish tank. After cleaning the tank she cleaned a pump in an outdoor pond. She developed a finger infection, swollen and red to purple in color, that also led to a swollen arm lymph node. It is not known if she got infected from the tank or the pond.

5….A middle-aged man fell in muddy water at low tide, scraping his outer calve on a houseboat barge which had barnacles attached to it. His leg became infected and after numerous surgeries they diagnosed him as having Mycobacterium marinum or fish tank granuloma. He was in the hospital for over 10 days with not much improvement and had surgeries to release fluid build up on his knee, along with a drainage tube that was inserted into his calve. They also removed some tissue from his leg. Recovery took a long time.

6….Woman slipped and fell from a dock, cutting her hands on oyster beds. Without benefit of x-rays, the ER attendant sewed shell fragments up in the thumb and middle finger on right hand which were then embedded for nearly 30 days before two corrective surgeries were done. Antibiotics (with sickening side effects) were taken for over 9 months.

7….Man had a freshwater fish die from, apparently, fish TB. At the time of fish death, fish was isolated in its own tank. About the same time, man developed bumps on his hand and fingers, which had an open wound at the same time. These bumps were biopsied at a dermatologist's and the diagnosis of M. marinum was confirmed. He took an antibiotic and the bumps (granulomas) began dissipating; his doctor told him the bumps would dissipate on their own but that it could take upwards of a year.

8….Man got pinched by blue crab, and infection developed; Mycobacterium marinum was diagnosed. After two surgeries and two months on three antibiotics, infection decreased. Third surgery was done to cut adhesions of tendons to flesh of palm and to clean out foci of infections.

9….Man in water offshore cut foot in several places on barnacles. Wounds were not healing after two months; and he was attended by two doctors who gave different antibiotics that did not work. His big toe was dark purple including a black toe nail. The toe changed colors - one day it was all black, next day it was dark purple, then black again. Long bout to healing.

10….Woman who was diabetic fell and cut her arm. The sore (at cut) got very large and open and pus- filled. It would not heal. She was taking antibiotics and started getting more sores around the original one. After seeing many doctors relatives took her to an infectious disease specialist. He told her he thought that she had a bacteria from her fish. She has a betta fish in her home and may have cleaned the bowl the day before she cut her arm. The sores were purple, some bigger than others and were pus filled.

1….Mycobacterium marinum might have survived on her arm for one day prior to her getting cut.
2….Diabetes leads to poor circulation, and lower temperature of an extremity, thus fish TB can easier spread in those with diabetes. People with diabetes also have a weakened immune system and would be more prone to infections.

Mycobacterium chelonae

1….A female (in her 30's) undergoing breast surgery was infected with Mycobacterium chelonae, apparently either while undergoing surgery or bathing after surgery, via infective bacteria being in the tap water. M. chelonae is usually found in soil and water and gets into public water reservoirs. Improperly treated water is then delivered to homes, hospitals, etc, where people can get infected. Numerous surgeries and various antibiotics did not cure the infection. Patient finally had infected breasts removed and reconstructive surgery begun.

Vibrio spp. (diagnosed or strongly suspected):

1….Vibrio parahaemolyticus infection is usually associated with ingestion of raw shellfish, recently there was a case locally where a man got arm infection while using a cast net. He almost lost his arm and life.

2….Vibrio parahaemolyticus infected the captain of fishing charter boat via his handling of fish. Took massive doses of antibiotics to cure.

3….Woman working in a shrimp culture facility got stuck by shrimp spines. Infection from Vibrio resulted; took several months to cure.

Herpetic whitlow:

1….A woman working in a seafood store got stuck while thawing shrimp 13 years ago. After much trouble with her hands, including the development of severe arthritis-like conditions, she was guessed at having M. marinum infections by some doctors, and herpetic whitlow by another. No causative agent has yet been isolated. Her problems continue.

Unknown infection:

1….A male freshwater marina worker was picking up trash along the water's edge of a lake. He did not wash his hands prior to going to rest room. Subsequently, he developed an external infection of the penis. It is suspected that boats were dumping raw sewerage into the lake, maybe even at the marina, and he picked up a human STD or other disease from the sewerage water on the trash he picked up.

2….Several years ago, while scraping the bottom of his boat, a man got infected after a small piece of the wire from the brush became lodged in the knuckle joint of one of his fingers. Symptoms were: pain in the joint radiating up his arm, a popcorn kernel-like covering spreading out from the center of the joint, and a symmetrical web of something like 5-o'clock shadow which pushed up through the surrounding tissue. Unknown cause.

3….A male got a bad eye infection after swimming in waters off a resort area. He had bilateral eye swelling, redness, soreness, thick opaque mucous discharge, and severe tearing. Infection was presumed to be due to his swimming in sewerage pollution.

4….Girl swam with the dolphins and sea lions at a facility; shortly thereafter she came down with a mysterious malady. Initially it was an infected eye, then a swollen head and pain. Apparently the infection entered via eye or tear ducts. Infection was presumed to be due to her swimming in animal sewerage pollution that was not handled by the filtration system at the facility.

5….Female siphoned a fish tank and ingested part of the foul water. She later developed a bad sore throat and tried to relate it back to tank. Unknown cause.

6….Female caught fish out of a polluted canal, and ended up with rash on left hand (which held fish to remove hook) and going up arm. Small round ulcers just under skin, sometimes raised welts, and itch. Had for over 3 years. Unknown cause.

7….Female working with shedding blue crabs. Her symptoms started with a rash on the back of head. Sores the size of a quarter erupted on her neck and went down her arms, buttocks, legs, and feet. Had 2.5 years, has seen nine doctors, and no diagnosis yet.

8….Man appeared to have developed an allergy to salt/sea water which started after he stepped on a piece of dead coral after visiting a tropical beach. It was a deep scratch which was more painful than the injury looked. The next time he swam in the sea was about one week later at another tropical beach, and he had small lumps on his legs, which were not irritating and went away after about an hour. The second time it was worse in his friend's salt water swimming pool, his hands swelled up after the palms felt itchy and his whole body was covered in the small lumps and he had a slight headache and didn't feel well. The third time he was just paddling about in tropical waters and he could feel his hands swelling and itching coupled with lumps on the legs.. Since his return to home he has seen a doctor and a blood test has confirmed that his antibodies are significantly raised. Doctor has suggested to avoid swimming in the sea and to take antihistamine tablets should he get this reaction again. Unknown cause.

Follow suggestions noted in Tank Safety/Fish TB   to avoid aquatic or tank infections. Also, with increasing human populations and improper sewerage treatment, it is dangerous to swim in many areas of the world, especially after rains that cause sewerage system overflows.

July 2004. Environmental News Service provided the following:

Texas Man Loses Both Legs to Bacteria
HOUSTON, Texas, July 29, 2004 (ENS) - Fun in the sun turned into a nightmare for two Houston men this week. One man had both his legs amputated and the other is in intensive care after they picked up a bacterial infection while fishing in Port O'Connor Bay on the Gulf of Mexico.

The Houston Chronicle reports that the men were infected with the vibrio vulnificus bacteria when they waded into the water with their fishing gear.

They had open cuts through which the bacteria entered, said a spokesperson for Citizens Medical Center in Victoria who declined to release the victims' names at their families' request.

In a separate incident, a Bay City fishing boat captain is in stable condition at Matagorda General Hospital in Bay City with what his doctors suspect is the same bacteria.

The vibrio vulnificus bacterium has been isolated from water, sediment, and plankton as well as oysters, clams and crabs located in the Gulf of Mexico, the Atlantic Coast as far north as Cape Cod and the entire U.S. West Coast. Cases of illness have also been associated with brackish lakes in New Mexico and Oklahoma.

Vibrio vulnificus is also found in raw oysters and shellfish and can cause illness or death if the shellfish is not cooked enough.

The presence of vibrio vulnificus is not associated with pollution. The bacteria is a naturally occurring marine organism that thrives in shallow, coastal waters in temperate climates throughout most of the world, according to the Florida Department of Health and Rehabilitative Services.

The Centers for Disease Control (CDC) states that an average of 50 culture-confirmed cases, 45 hospitalizations, and 16 deaths are reported each year from the Gulf Coast region - Alabama, Florida, Louisiana, Mississippi, and Texas.

Nationwide, there are as many as 95 cases - half of which are culture confirmed - 85 hospitalizations, and 35 deaths, the CDC reports.

Infections are seasonal. Over 85 percent occur between May and October. According to the CDC, environmental factors, such as warm water and moderate salinity, can increase the number of vibrio vulnificus organisms in shellfish.

The vibrio vulnificus infection is fatal in 50 percent of cases after it enters the bloodstream, experts say.