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Category Archives: Vibrio
In 2017, five EU/EEA countries reported 17 laboratory-confirmed cases of cholera, which was in the range of previous years. All cases were infected outside of Europe.
Research – Long-Term Depuration of Crassostrea virginica Oysters at Different Salinities and Temperatures Changes Vibrio vulnificus Counts and Microbiological Profile
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.
RASFF-Vibrio parahaemolyticus in frozen squid (Loligo spp.) from India in Greece
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).
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.
Vijaywada: Research scholars from Sri Venkateshwara Veterinary University found that the catla fish being sold in the market is polluted by superbugs that can cause several health problems ranging from simple fever, vomiting and abdominal pain to serious issues like cholera, blood stream infection and septic shock.
According to a report in The Times of India, 15 different species of the bacterium Vibrio, including Vibrio cholerae, the bacterium responsible for cholera outburst, were identified in the fish. These bacteria are being called as superbugs because they are resistant to various potent antibiotics.
The superbugs were found in catla fish, a commercially popular freshwater fish variety. Yet the researchers fear that other species of fish might also get polluted by superbugs if they are caught from the contaminated water bodies.
T Srinivasa Rao, one of the researchers, told TOI that though proper and prolonged cooking can help get rid of the superbugs, their antimicrobial resistance is a matter of concern.
The Centre for Food Safety (CFS) of the Food and Environmental Hygiene Department today (November 26) announced the test results of a recently completed seasonal food surveillance project on the microbiological quality of poon choi. Thirty samples were collected and all passed the tests.
A CFS spokesman said, “As poon choi is popular for gatherings during winter and there were previous cases of bacterial food poisoning associated with poon choi, the CFS has continued to conduct a seasonal food surveillance project this year to assess the microbiological quality of poon choi. A total of 30 poon choi samples were collected from different retailers (including online retailers) for testing of common food poisoning organisms including Bacillus cereus, Clostridium perfringens, Salmonella, coagulase-positive staphylococci organisms and Vibrio parahaemolyticus.”
Despite the satisfactory results of all samples tested, the spokesman reminded people to be careful when purchasing and enjoying this seasonal delicacy. He advised consumers to order poon choi from licensed and reliable shops, avoid prolonged storage of poon choi at room temperature to reduce the risk of bacteria growth, reheat poon choi thoroughly before consumption, consume cooked or reheated poon choi as soon as possible or keep the food at temperatures above 60 degrees Celsius, and stop consuming the food if it tastes or smells abnormal.
“The public should also maintain a balanced diet and avoid eating too much food with high levels of energy, sugar, salt or fat,” the spokesman said.
He also appealed to the food trade not to entertain orders beyond handling capacity. Traders are reminded to check the quality of food and ingredients when they are delivered to them. In addition, to reduce the risk of food poisoning, they should avoid preparing food too far in advance and take note of the temperature in storing, transporting and preparing food.
“All food and food ingredients should be stored at safe temperatures while perishable items should be stored at 4 degrees C or below. The cooling time of cooked food should be reduced as far as possible, for example, by dividing food into smaller portions or placing it in shallow containers. When transporting hot poon choi, it should be kept at above 60 degrees C, and for chilled poon choi, it should be kept at 4 degrees C or below,” the spokesman said.
“Traders should also provide clear advice on the proper methods of storing and reheating of poon choi to consumers so as to further reduce the risk of food poisoning due to improper handling,” he added.
The CFS will continue its surveillance of poon choi available in the market to ensure food safety and protect the health of the public.