Even before the recent sewage spill, the murky Ala Wai Canal has long had a reputation as an incubator of hazardous bacteria.

But germs with the potential to kill also can be found lurking in unpolluted coastal waters, idyllic mountain streams and your own backyard. They can even be in your nose and throat and on your skin.

The April 6 death of Oliver Johnson six days after he plunged into the sewage-contaminated waters of the Ala Wai Boat Harbor has increased fears of the invisible threat posed by virulent germs invading through cuts and scrapes. Johnson died from organ failure due to septic shock brought on by an infection of Vibrio vulnificus, a bacterium in the same family that causes cholera.

More common in Hawai'i than V. vulnificus are the potentially fatal bacterial infections leptospirosis, staphylococcus aureus and group A streptococci, which can lead to necrotizing fasciitis, known as "flesh-eating" disease.

State health officials say fatalities from these four bacterial infections are still relatively rare, but people with open wounds or weakened immune systems are at increased risk. Certain conditions, such as warm seawater or freshwater streams and ponds likely to be contaminated with animal urine, boost the chances of exposure.

However, many bacterial infections with severe complications are just a case of bad luck.

"With all the people who get cuts and abrasions throughout the state of Hawai'i, only a small number come out with serious life-and-limb infections. It's an uncommon event, unless you're unlucky and pick up the wrong bug, the one that produces those chemical toxins" that can rapidly advance through the human body, said Dr. Scott Hoskinson, an infectious disease specialist at Maui Memorial Medical Center.

"Unfortunately ... with those strains that can be very dangerous and tend to kill people; there is no way by looking at the skin to tell whether it is a more aggressive strain," he said.

What scares most people about these infections is the speed at which they can ravage victims. While all can be subdued in their early stages with antibiotics, patients can be fooled by flu-like symptoms and may delay seeking medical treatment until it's too late.

VIBRIO INFECTIONS KILL

V. vulnificus lives in warm seawater and is known mostly in the Gulf Coast. In Hawai'i, there have been five deaths from Vibrio infections since 2001, four from V. vulnificus.

The majority of the state's Vibrio cases are from wound or blood infections and ear infections, said Michele Nakata, chief of the Department of Health's Disease Investigation Branch. Among healthy people, the bacteria can cause vomiting, diarrhea and abdominal pain. V. vulnificus infections can be easily cured within the first day or two, but if the infection invades the bloodstream, there is a 50 percent chance of survival, according to the Centers for Disease Control and Prevention.

Dr. Alan Tice, an infectious disease specialist with the University of Hawai'i's John A. Burns School of Medicine, said V. vulnificus is from a family of bacteria that is "particularly happy" in seawater. It usually does not attack people, he said, but can adapt into an invasive form that can overwhelm the body's defenses, especially in patients — like Johnson — with chronic liver disease.

"Vibrio is unusual because most organisms are transmitted by one means, either by ingestion or through open wounds. But Vibrio can infect you both ways," said microbiologist Roger Fujioka of the UH Water Resources Research Center. And once in your body, the bacteria can develop a protective coating and other mechanisms to defeat the body's germ-fighting defenses.

"These organisms don't have brains but they know what they want and they can sense their environment, and if there's something good for them, they go for it," Fujioka said. "Once it progresses to a certain level, it's too late. It's already multiplying in the system all through your body. You reach a certain level where antibiotics just won't work."

In Johnson's case, the deadly infection spread from his injured foot.

The 34-year-old mortgage broker fell or was pushed into the Ala Wai Harbor on March 31. He received outpatient medical care at The Queen's Medical Center, but the following day complained of pain in his legs. On April 2, he was taken by ambulance to Queen's, where he went into septic shock and was placed in a medically induced coma. His right leg was amputated the next day in an unsuccessful attempt to halt the spread of the infection.

When Johnson died April 6, his heart, liver and kidneys had shut down, his intestines had been eaten up by bacteria and his bowels were rupturing. His body had swollen to three times its normal size.

V. vulnificus is the same "bug" that killed a 72-year-old man on Feb. 26, 2001, two days after he'd gone swimming in a popular saltwater pool next to the ocean at Ahalanui Beach Park in Puna. The thermal pond is warmed by underground volcanic sources, reaching temperatures of up to 93 degrees.

Herbert Wiesenfeld, a retired psychoanalyst from Carmel, Calif., was suffering from psoriasis, a chronic skin condition, when he entered the water at Ahalanui. He emerged from the pond with legs bloodied from where his scabs had been nibbled off by the little fish that live in the warm water.

The next morning Wiesenfeld exhibited flu-like symptoms and his legs were swollen and red. As the day wore on he became disoriented and agitated. He was taken to Hilo Medical Center that night, and died the following day despite massive doses of antibiotics.

A 77-year-old man who swam at the pond in October 2002 also became seriously ill but recovered.

RISK OF OPEN WOUNDS

At the urging of Wiesenfeld's widow, the state Health Department advised the county in late 2002 to post signs warning swimmers that the water at Ahalanui is not disinfected and that people with open wounds should not swim in thermal ponds because of the risk of bacterial infection.

But residents and visitors continue to flock to Ahalanui Beach Park, with as many as 350 at once in the heated pool on a sunny weekend day, according to county ocean safety officer Chris Birkholm.

Jeremy Enos of 'Ainaloa was there recently with his 3-year-old daughter, Amaya. Enos, 27, said he has been swimming at Ahalanui since he was a small boy and has never gotten sick. He wasn't aware of Wiesenfeld's death but even with the warning signs, Enos said he is not concerned about infections.

But his father, Marvin Enos, 46, refuses to swim there. The elder Enos sat high and dry on the low rock wall that surrounds the pond, watching his sons and grandchildren splash in the pond.

"I just ain't gonna take my chances," he said.

Birkholm said he used to swim laps in the pool, but stopped because of repeated ear infections. Still, he considers the water to be clean, noting the state tests the water quality weekly.

"If you're healthy and in good shape, there's usually no problem with getting in this water," Birkholm said.

Fujioka said research indicates that V. vulnificus is more prevalent in locales such as Hawai'i with warmer year-round ocean temperatures. The same conditions also encourage year-round ocean recreation, creating more opportunities for infection.

He said to be wary of swimming in thermal ponds and even the ocean, if you have open cuts, ill health or other conditions that could invite V. vulnificus.

"It's not something you would worry about unless you have liver or immuno problems. It doesn't seem to affect people engaged in ordinary activities, but it's out there," he said.

FRESHWATER BACTERIA

Hawai'i's icy-cold streams and mountain pools have their own appeal — and risks. Many of these freshwater sources contain bacteria from the urine of feral pigs, goats and rodents infected with leptospirosis. Humans become infected by swallowing contaminated water or through the eyes or nose, or broken skin.

The state has the highest rate of leptospirosis in the country, and tourists, especially, may not be aware of the threat, Tice said. "You have to be careful and cautious about it. We have some unusual organisms that can cause disease," he said.

People infected with leptospirosis may suffer mild or no symptoms at all, and death is rare, although it is believed cases are underreported because patients may not associate their illness with recent outdoor activity. There have been nine fatalities from leptospirosis contracted in Hawai'i since 1974. The two most recent deaths occurred in the past two years and involved visitors from the Mainland who died after returning home.

The disease was not diagnosed in Pahoa college student Simon Hultman, 22, until after he died Jan. 26, 2004, at a Maryland hospital. Hultman had gone hiking and swimming while visiting his family on the Big Island during the holidays. He returned to Washington College in Chestertown and five days later went to a hospital emergency room complaining of fever and other flu-like symptoms. He died a week later.

Physicians interviewed by The Advertiser were split on whether to swim or wade in freshwater streams and ponds. Tice avoids that activity, preferring to surf in the ocean. "I wouldn't do it. It's not a good idea," he said.

Hoskinson said he does swim in freshwater sources, but looks for briskly flowing streams and stays away from stagnant ponds. Public health officials also advise against dunking your head underwater, if possible.

STAPH INFECTIONS

The commonly occurring bacteria staphyloccocus and streptococcus don't live in the sea or in mountain streams, but in and on your body.

"Nobody has a great reason for it, but in tropical climates, staph is the most common skin-associated infection. And since it's prevalent on the human body and in the environment, there's nothing specific you can do to avoid the bacteria," Hoskinson said.

The Islands' warm and moist climate likely encourage the bacteria to multiply more easily than in colder and drier regions, he said, and people here wear less clothing and footwear, with less protection from abrasions and cuts.

People may carry group A streptococci in their throat or on the skin and have no symptoms of illness. Most infections are relatively mild illnesses such as strep throat or impetigo. On rare occasions, these bacteria can cause severe and even life-threatening diseases.

Nearly a year after his 47-year-old daughter died of an infection caused by a combination of staph and strep bacteria, Charles Kauluwehi Maxwell Sr. is still stunned by the speed at which the disease destroyed her body.

"It's on my mind every day," said Maxwell, a noted Hawaiian cultural specialist and activist.

Debbie Kamali'i, a kumu hula who worked with inmates at the Maui Community Correctional Center, suffered a superficial scratch on her inner right thigh on May 20. She began feeling ill, and within two days had a fever and chills and was vomiting. "She thought she was coming down with the flu," Maxwell said.

Because the scratch was in a hard-to-see area, Kamali'i was unaware of the festering wound on her thigh until the morning of May 23, when her family convinced her she needed to be taken by ambulance to Maui Memorial Medical Center.

"The only time we found it out was in the emergency room when the nurse turned her over and, 'Oh, my god, what is this rash from the scratch?' It was huge," Maxwell said. Kamali'i became so bloated from the infection that her Hawaiian bracelet had to be cut from her wrist.

"In a matter of an hour and a half of arriving, the doctors were telling us that the infection was shutting down her functions and that she might not make it," Maxwell said.

Kamali'i died that night.

"We had no clue she was that sick. It was like a bad dream," he said.

Maxwell, who is diabetic, said he more closely monitors any skin wounds. "The minute I have a sore, I go right to the doctor," he said.

A thorough cleansing with soap and water is still the best protection against infections, doctors said. Wounds should be closely watched over the first 24 to 48 hours.

"If it's not healing and it's more swollen, red and painful, and there's a fever and flu-like symptoms, that's the giveaway," Hoskinson said.

Tice said problems with antibiotic-resistance bacteria mean early medical care for suspected infections is essential to reduce the chance of a deadly outcome. "See a doctor earlier than usual if you see a problem," he said.

Reach Christie Wilson at cwilson@honoluluadvertiser.com.