Enjoy the Water, but be Smart and Avoid the Vibrios

After the particularly chilly winter of 2014, local residents will head to the water for fishing, swimming, and a host of other water activities that define our lives here on the coast. Most people are unaware of a dangerous flesh eating bacterium, Vibrio vulnificus, which thrives in our coastal salt water. Scientists have identified more than 100 distinct species of Vibrio bacteria.
But only a few are pathogenic and harmful to humans. Among those are 
Vibrio cholerae, 
the bacterium that causes cholera which still kills over 500,000 people annually. CDC states that Vibrio parahaemolyticus causes on average about 45,000 cases of disease in the U.S. each year, 86% of which are food-borne gastorenteritis. By comparison, CDC estimates that Salmonella causes 1 million cases of gastroenteritis annually, Shigella 500,000 and Listeria 1,600. The V. parahaemolyticus death rate is low, about 2% for gastroenteritis and 20-30% for wound-related cases.

Vibrio vulnificus bacterium. Source: safeoyster.org

The subject of this article, Vibrio vulnificus, can cause both food-borne and wound-related illnesses. The CDC reports a long-term average of 96 cases of serious Vibrio vulnificus infection per year, including food-borne and wound-related. The overall death rate is slightly over 50%, said by many experts to be the highest human fatality rate for any bacterium. According to FDA, 90% of all Vibrio vulnificus illnesses (morbidities and motalities) in the U.S. result from consumption of raw Gulf coast oysters. However, this article focuses on wound-related illness caused by Vibrio vulnificus.
Vibrio vulnificus is not the only Vibrio known to cause wound infections, but it is the most likely to cause disease. During the winter, populations of Vibrio vulnificus are lower and seem almost dormant, so they present little threat to the general public. As temperatures rise, Vibrio vulnificus multiplies. Warmer weather also brings coastal residents and visitors into contact with the water. This increases the chance of encountering the organism. Infections are seasonal; over 85% occur between April and October. Read on to learn about the threat and how to stay safe.

Every Gulf state from Florida to Texas has reported Vibrio vulnificus wound infections. Here in Ocean Springs, Joseph Smith contracted Vibrio while fishing in 2012 and physicians had to remove his leg. In Florida, there were nine deaths in 2012 and 13 deaths in 2011 attributed to the bacterium. Last year in June and July at Grand Isle, Louisiana there were several cases of wound infections of Vibrio vulnificusthat resulted in hospitalization and one death.

A Gonzales, Louisiana man contracted Vibrio vulnificus after scraping his leg on barnacles while fishing in Grand Isle, Louisiana in June 2013.  Garey survived and kept his foot, but only because his attending physician knew Vibrios. Even closer to home, Mississippi coast resident Joseph Smith lost his right leg to a Vibrio vulnificus infection he believes he contracted on a fishing trip.
A Vibrio Vulnificus infection showing redness and swelling, soon after the patient was admitted to the emergency room. Photo courtesy of Louisiana Sportsman.
Later, after multiple surgeries to remove affected tissue. The patient required weeks of ongoing wound care following his hospital stay. Photo courtesy of Louisiana Sportsman.

The CDC states that Vibrio infections may be under-reported. Since 1988, the CDC has maintained a voluntary surveillance system for culture-confirmed Vibrio infections in Alabama, Florida, Louisiana, Mississippi, and Texas. Between 1988 and 2006, CDC received reports of more than 900 infections from the Gulf Coast states. In 2007, surveillance was expanded to national notification of infections caused by any Vibrio species. Wounds account for approximately 60% of all U.S. Vibrio vulnificus cases.

Vibrio vulnificus cases in the U.S. by year 1998-2004
Dark purple bars show total cases. Light pink bars show cases resulting from eating shellfish. The difference between the two represent wound-related cases. Source: safeoyster.org

Dr. Jay Grimes, Professor of Marine Microbiology at GCRL, reports that with global climate change, Vibrio vulnificus populations are increasing as water temperatures rise. The rising water temperatures promote the increase in Vibrio vulnificus not only in our own coastal waters.  New cases of the bacterium are being found in waters where they were not previously perceived as a threat.

Small wounds can happen easily when you are out fishing or enjoying some time on the beaches, for example, getting hooked on your own fishing tackle or stepping on an oyster shell. At the time, it may seem an insignificant injury.  But, the Vibrio vulnificus bacterium can enter through a new wound or through an existing wound, like a tiny cut, scratch or even a mosquito bite. For most healthy individuals, any infection or irritation is minor and hardly noticed. The case is different for people who have weakened immune systems. The bacterium invades the bloodstream, potentially causing a severe and life-threatening illness. Vibrio wound infections happen fast; symptoms may become evident in only four hours.

For prevention, people with open wounds should avoid contact with sea water. But, if you have a wound exposed to warm saltwater and see any combination of redness, swelling, fever, chills and experience pain the get to the hospital immediately and be sure to tell the physician that your wound was exposed to salt water. Physicians recommend that you don’t try to “tough it out!" Dr. Ekenna Okechukwu, Infectious Disease Specialist and Doctor of Internal Medicine at Singing River Health Systems, said The earlier you seek help, the more likely a good outcome is possible. Do not delay in seeking help. Treatment of a Vibrio vulnificus wound infection will usually include antibiotics and surgery in cases of wound infection.

A Vibrio vulnificus infection can be tricky to diagnose and treat.  And many clinicians and physicians have not seen a case first-hand. Anybody - young, old, male, or female - can be exposed to this fast-moving infection, but people who have weakened immune systems are at the highest risk. Dr. Ekenna Okechukwu, states “People with underlying diseases like liver cirrhosis or other chronic liver disease, chronic alcoholism, cancer, or persons on treatment with immunosuppressive drugs, including chemotherapy or steroids may be more prone to get sick and complicated infections, especially if they have an open wound.” One study reported that people with compromised immune systems were 80 times more likely to develop Vibrio vulnificus bloodstream infections than healthy people.

Avoid Wounds

When fishing, harvesting oysters, or handling crab traps, use caution and wear gloves where practical  to prevent wounds, flush any wounds quickly with sterile water and treat them with hydrogen peroxide and povidone-iodine (e.g., BetadineR). Wear protective coverings on your feet and, in general, use caution when in and around coastal waters. Dr. Grimes emphasizes that an ounce of prevention is worth pounds of cure.

If You Have a Wound

If you get a small wound while you are out enjoying the Gulf Coast or enter the water with a small wound or sore, and begin to see symptoms of an infection, don’t take chances.  Immediate medical attention and treatment quickly can be the difference whether you keep all of your limbs and your life. Dr. Grimes recommends that anyone who has a wound exposed to saltwater follow these steps.

Avoid a Vibrio vulnificus Infection in a Wound Exposed to Warm Saltwater

  1. Flush out wound with sterile water. Use bottled water if you are on a boat.  Do not use sea water.
  2. Wash the wound with soap and water.
  3. Flush and clean the wound with hydrogen peroxide. Disinfect with a generous application of Betadine. Hydrogen peroxide and Betadine are available at all drug stores and should be included as part of your first aid kit on any boat.
  4. If your wound starts to swell and turn bright red, go immediately to the closest emergency room. Inform the attending physician about the injury and that it was exposed to saltwater. Tell the ER physician you suspect a Vibrio infection.

The Bottom Line

While Vibrio wound infections present a serious danger in warm saltwater, thankfully, they are not common and rarely affect those with healthy immune systems. Dr. Grimes stresses that common sense precautions will help you avoid infections, and that prompt diagnosis and treatment of a Vibrio infection saves lives and limbs.


Seminar for Clinicians

Scientists here at the Gulf Coast Research Laboratory want to help health care professionals learn the key indicators for spotting Vibrio vulnificus infections in patients. Dr. Grimes was part of a team that offered a half-day program titled Coastal Concerns for Clinicians on May 3, 2014. This program alerted and educated healthcare providers on Vibrio vulnificus, parasites, viruses, harmful algae, and other waterborne threats to humans here in our coastal region.