Category Archives: Vibrio vulnificans

Research – Long-Term Depuration of Crassostrea virginica Oysters at Different Salinities and Temperatures Changes Vibrio vulnificus Counts and Microbiological Profile

Journal of Food Protection

Previous short-duration depuration studies with the eastern oyster (Crassostrea virginica) demonstrated difficulty in achieving significant naturally incurred Vibrio vulnificus population count reductions. The present study used long-duration depuration (14 days) at controlled temperatures (10 or 22°C) and salinities (12, 16, or 20 mg/g). All depuration temperature–salinity combinations significantly reduced V. vulnificus counts, with greatest reductions seen in 12 mg/g, 10°C seawater (2.7-log CFU/g reduction) and in 20 mg/g, 22°C seawater (2.8-log reduction). Mesophilic vibrios dominated the overall microflora of freshly harvested oysters, whereas refrigerated storage selected for psychrotrophic bacteria (Pseudomonas spp., Aeromonas spp., Shewanella spp., Psychrobacter spp.) as well as did depuration at 10°C (Pseudoalteromonas spp., Shewanella spp., Vibrio spp.). Depuration at 22°C retained dominance of mesophilic vibrios, including pathogenic species, followed by Shewanella spp., Pseudoalteromonas spp., and Photobacterium spp. Although aerobic plate counts were lower in 22°C depurated oysters (5.0 log versus 6.0 log) compared with 10°C, depuration at 10°C offered greater V. vulnificus population reductions than depuration at 22°C. This advantage was only seen at 12 mg/g salinity, with no impact at 16 and 20 mg/g salinities. No depuration treatment reduced V. vulnificus counts to nondetectable levels. Use of prolonged depuration may be a helpful intervention to control V. vulnificus populations in oysters.

Research – How to kill pathogens on seafood

Food Processing

Controlled release antimicrobial film makes seafood safer.

Seafood may be contaminated with bacterial pathogens, such as Vibrio and Salmonella, which can survive long-term freezing conditions. Vibrio naturally occur in marine environments and Salmonella can contaminate seafood during production or processing and both are concerns for the seafood industry.

However, a solution may be at hand. A biodegradable, edible film made with plant starch and antimicrobial compounds may control the growth of foodborne pathogens on seafood, according to a group of international researchers.

Catherine Cutter, professor of food science, Penn State, explained, “We have the ability to develop a film with antimicrobial activity that can kill foodborne pathogens on food surfaces. Given the recent outbreaks that we have seen with a number of food products, coming up with something that can be used by the industry to kill microorganisms on the surfaces of food is a noble area of research to investigate.

Vibrio and Salmonella are somewhat susceptible to freezing,” Cutter said. “So, if you treat bacterial cells with antimicrobials and then freeze them, the approach can be more lethal.”

Freezing does not kill bacteria. However, when freezing food, ice crystals can form from the water in food. The ice crystals, Cutter said, can act like “daggers” and pierce the bacterial cell wall, causing damage to the cell.

Researchers used a blend of thermoplastic starch, a biodegradable polymer made from tapioca powder and a gelatin coating containing antimicrobials known as Nisin Z and lauric arginate (LAE).

 

USA – Vibrio vulnificus in Florida in 2018

Outbreak News Today

CDC Vibrio

Florida state health officials have reported 39 Vibrio vulnificus cases through Dec. 14, down from last year’s total of 50. Of this total, nine fatalities have been reported.

Lee County saw the most with four cases, while nine counties reported two cases each. Deaths were reported from Hillsborough (2), Dade, Indian River, Jackson, Okaloosa, Sarasota, Volusia and Walton counties.

People can get infected with Vibrio vulnificus when they eat raw shellfish, particularly oysters. The bacterium is frequently isolated from oysters and other shellfish in warm coastal waters during the summer months. Since it is naturally found in warm marine waters, people with open wounds can be exposed to Vibrio vulnificus through direct contact with seawater. There is no evidence of person-to-person transmission of Vibrio vulnificus.

Vibrio vulnificus can cause disease in those who eat contaminated seafood or have an open wound that is exposed to warm seawater containing the bacteria. Ingestion of Vibrio vulnificus can cause vomiting, diarrhea and abdominal pain. Vibrio vulnificus can also cause an infection of the skin when open wounds are exposed to warm seawater; these infections may lead to skin breakdown and ulcers.

USA – Flooding from Hurricane Michael creates food safety issues across South

Food Safety News

Strong winds and heavy rain continue to wreak havoc across parts of the South today as Hurricane Michael meanders out of Georgia and heads up the mid-Atlantic Coast.

In addition to the devastating damage that is immediately visible today, less obvious hazards in the wake of the massive storm are expected to last weeks. Food safety dangers come in various forms and can cause severe illnesses and deaths as floodwaters recede.

Among the most vulnerable foods are fresh fruits and vegetables. They are breeding grounds for pathogens when power outages cause the loss of refrigeration and temperature control. Fresh produce that comes into contact with floodwater can be instantly contaminated with a wide range of bacteria, viruses and parasites.

The toxic composition of floodwater is such a serious food safety hazard that federal law prohibits the sale, distribution or donation of any produce or other food crops from fields that are flooded. Special inspections are required before such crops can even be used for animal feed. 

USA Today

Hurricane Michael leaves behind a treacherous, dangerous landscape that will likely pose risks to human health for weeks to come, experts say.

The water itself can carry bacteria and viruses that pose a major health hazard.

Among the medical dangers are cholera, Hepatitis A and vibriosis, said Dr. Robert Glatter, an emergency room physician at Lenox Hill Hospital in New York City. Glatter said storm victims need to stay focused on staying healthy while they await recovery efforts. That may mean not rushing outside as soon as the skies clear.

“Don’t panic— try to take things one step at a time when you feel overwhelmed,” he said.

South Korea – Man, 71, had hand amputated when skin started rotting 12 hours after eating sushi – Vibrio vulnificans

New England Journal of Medicine 

71-year-old man presented to the emergency department with a 2-day history of fever and excruciating pain in his left hand that had developed 12 hours after eating raw seafood. He had a history of type 2 diabetes mellitus and hypertension and was undergoing hemodialysis for end-stage renal disease. At the time of presentation, hemorrhagic bullae measuring 3.5 by 4.5 cm had developed on the palm of his left hand (Panel A), and erythematous swelling with confluent tense bullae and ecchymoses had developed on the dorsum of the hand and forearm (Panel B). Surgical intervention was performed urgently, and Vibrio vulnificus was isolated from the bullae. Postoperatively, the patient received intravenous ceftazidime and ciprofloxacin. V. vulnificus can cause skin infections after wound exposure to contaminated seawater, as well as primary septicemia through the consumption of contaminated raw or undercooked seafood. Patients with immunocompromising conditions, including chronic liver disease and cancer, are at increased risk for infection and complications. Despite treatment, the skin lesions progressed to deep necrotic ulcers, and amputation of the left forearm was performed 25 days after presentation. The patient did well after the surgery and was discharged home.

USA – Third case of Vibrio confirmed in Mobile County

WKRG 

MOBILE, Ala. (WKRG) — The third case of Vibrio in 2018 has been reported to the Mobile County Health Department (MCHD). The case is currently under investigation by MCHD’s Infectious Diseases & Outbreak division.

MCHD says the exposure took place while cleaning crabs in the coastal waters of Mobile Bay. The species has been identified as Vibrio vulnificus. Necrotizing fasciitis — an infection that results in the death of the body’s soft tissue — was present in this case.

Vibrio bacteria naturally live in certain coastal waters and are present in higher concentrations between May and October when water temperatures are warmer. However, the bacteria can be present throughout the year in some areas. While Vibrio bacteria can enter the body through a break in the skin, it can also come from consuming contaminated seafood.

The Alabama Department of Public Health has issued a news release titled “Do not enter bodies of water if you have cuts or abrasions; if injured, clean wound at once to reduce risk of infection.” Here is the link: http://www.alabamapublichealth.gov/news/2018/06/15.html/

Of the more than 70 species of Vibrio that exist, about a dozen can cause human illness — known as Vibriosis. The Centers for Disease Control and Prevention estimates that each year in the United States 80,000 individuals become sick with Vibriosis, and 100 people die from their infection. About 52,000 of these illnesses are estimated to be the result of eating contaminated food.

USA- Alabama: Mobile County reports 2nd Vibrio case

Outbreak News Today 

 

Vibrio_vulnificus_01

Image CDC Enter a caption

The Mobile County Health Department (MCHD) reported Monday on the second case of Vibrio in 2018.  The species has been identified as Vibrio vulnificus.

The exposure took place while swimming in either Mobile Bay or Gulf of Mexico waters. Necrotizing fasciitis — an infection that results in the death of the body’s soft tissue — was not present in this case. The case is currently under investigation by MCHD’s Infectious Diseases & Outbreak division.