Credit Florida DOH
# 7830
As a native Floridian who has lived a good deal of his life aboard boats or near the ocean, I’m quite aware of both the lure - and the hazards - of Florida’s waters. Like anyplace else, we have our fair share of local dangers. But the ones that tourists tend to worry about; alligator or shark attacks are actually quite rare.
A bit more common – but not well appreciated - are some of the naturally occurring pathogens that can be found in our local salt and fresh waters (but not restricted only to Florida).
While exceeding rare, the `killer amoeba’ called Naegleria Fowleri gets a lot of press attention each summer, as its victims are usually children, and the outcome is almost always fatal. We generally see 2 or 3 cases a year across the southern states each year, usually linked to swimming in stagnant freshwater lakes or ponds.
In mid-August, in Florida Reports Naegleria fowleri Infection we learned of an 12-year-old boy with the infection, in July (see Arkansas: Naegleria fowleri Shuts Water Park) the victim was a 12-year-old girl, while just last month, in Louisiana: St. Bernard Parish Water Supply Tests Positive For Naegleria Fowleri we saw the rare acquisition of the parasite from tap water.
But there is another waterborne pathogen, called Vibrio vulnificus, that is a naturally occurring bacteria that can be found in the warm coastal waters of the gulf coast states (Alabama, Florida, Louisiana, Texas and Mississippi). Over the past week, local and national media have reported on 26 infections, and 9 fatalities this year in Florida.
An active year, but hardly a record. As in 2011 Florida reported 35 cases, and 13 deaths.
Ingestion of Vibrio vulnificus can cause gastrointestinal symptoms, but for healthy people, rarely causes serious illness. The State of Florida warns, however: Vibrio vulnificus infections can be a serious concern for people who have weakened immune systems, particularly those with chronic liver disease
The most common route of infection is by eating raw or undercooked shellfish (oysters, mainly). Between 1988 and 2003, Florida reported 157 Vibrio infections from oyster consumption. Of those, nearly half (45%) died.
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Which is why I’ll take my oysters deep fried or steamed, thank you.
It is also possible to contract this infection from swimming, or wading, in contaminated waters. From the CDC’s Vibrio Vulnificus website:
V. vulnificus can cause an infection of the skin when open wounds are exposed to warm seawater; these infections may lead to skin breakdown and ulceration. Persons who are immunocompromised are at higher risk for invasion of the organism into the bloodstream and potentially fatal complications.
These skin infections can prove quite nasty, and the press often refers to it as a `flesh eating bacteria’. Antibiotics and extensive debridement of necrotic tissue are the standard treatments, and in some instances amputation is required.
It should be noted that millions of people swim in the Gulf and Atlantic waters off Florida every year, and only a small handful are affected. Frankly, you have a far better chance of drowning than acquiring this bacterial infection. Nevertheless . . . .
In 2007, V. vulnificus became a reportable illness to the CDC, and so surveillance and reporting has become more detailed. Here, from the State of Florida Department of Health, is a breakdown of V. vulnificus infections in the state over the past 6 years.
Below is a breakdown of cases in Florida since 2008:
2008 = 15 cases, 5 deaths
2009 = 24 cases, 7 deaths
2010 = 32 cases, 10 deaths
2011 = 35 cases, 13 deaths
2012 = 27 cases, 9 deaths
2013 = so far 26 cases, 9 deaths and of those deaths:
- 2 – unable to determine exposure history
- 3 – consumed raw oysters
- 4 – likely exposure to seawater
2013 deaths occurred in the following counties:
- Broward (2 qty.) Flagler Glades Lee Leon Monroe Okaloosa Walton
This from the Florida’s DOH press release of October 1st, 2013.
How common is Vibrio vulnificus infection?
Vibrio vulnificus is a rare cause of disease, but it is also underreported. Between 1988 and 2006, the Centers for Disease Control and Prevention (CDC) received reports of more than 900 Vibrio vulnificus infections from the Gulf Coast states, where most cases occur. Before 2007, there was no national surveillance system for Vibrio vulnificus, but CDC collaborated with Alabama, Florida, Louisiana, Texas and Mississippi to monitor the number of cases in the Gulf Coast region. In 2007, infections caused by Vibrio vulnificus and other vibrio species became nationally notifiable.
What are some tips for preventing Vibrio vulnificus infections?
- Do not eat raw oysters or other raw shellfish.
- Cook shellfish (oysters, clams, mussels) thoroughly.
- For shellfish in the shell, either a) boil until the shells open and continue boiling for 5 more minutes, or b) steam until the shells open and then continue cooking for 9 more minutes. Do not eat those shellfish that do not open during cooking. Boil shucked oysters at least 3 minutes, or fry them in oil at least 10 minutes at 375°F.
- Avoid cross-contamination of cooked seafood and other foods with raw seafood and juices from raw seafood.
- Eat shellfish promptly after cooking and refrigerate leftovers.
- Avoid exposure of open wounds or broken skin to warm salt or brackish water, or to raw shellfish harvested from such waters.
- Wear protective clothing (e.g., gloves) when handling raw shellfish.
And as a final note, with a tropical system trying to wind up in the Gulf of Mexico this weekend, V. vulnificus infections are a particular concern after a hurricane or tropical storm, as salt or brackish waters can be forced up onto land, and people may be wading through it during the recovery effort.
The follow excerpt is from the CDC’s Vibrio vulnificus After a Disaster webpage.
Concerns in hurricane-affected areas
Persons with immunocompromising conditions and especially those with chronic liver disease should avoid exposure of open wounds or broken skin to warm salt or brackish water, and avoid consuming undercooked shellfish harvested from such waters. More information on caring for wounds may be found in the fact sheet Emergency Wound Care After a Natural Disaster available on the CDC Hurricane website.
After a coastal flood disaster, large numbers of persons with illnesses that affect their resistance to infection may be exposed to seawater. Injury prevention is especially important for high-risk persons. Wounds exposed to seawater should be washed with soap and water as soon as possible, infected wounds should be seen by a doctor, and clinicians should aggressively monitor these wounds.
<SNIP>
Further information about Vibrio vulnificus can be found in Management of Vibrio vulnificus Wound Infections.
