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What to know about raw oysters and flesh-eating bacteria
Author of the article:Washington Post
Washington Post
Lindsey Bever
Published Sep 10, 2025 • 4 minute read
Join the conversation
raw oysters
Raw oysters
Is it true that raw oysters are dangerous?
Many raw dishes such as steak tartare and sushi carry a risk of illness.
But raw oysters “are among the riskiest foods that we consume regularly,” said Benjamin Chapman, the department head of agricultural and human sciences at North Carolina State University.
In recent months, multiple states have reported cases of a deadly flesh-eating form of a bacteria that, in rare cases, can be spread by raw oysters. Vibrio vulnificus – which is usually spread through open wounds in contaminated seawater, but in an estimated 10 percent of cases can come from eating raw or undercooked shellfish – has led to at least five deaths in Florida and four in Louisiana, state health officials said.
Oysters and other mollusks such as clams and mussels live in coastal waters that contain bacteria, viruses and other contaminants. Some oysters may carry these pathogens, including the bacterium Vibrio that causes an infection called vibriosis.
Both Vibrio parahaemolyticus and Vibrio vulnificus can cause nausea, vomiting, diarrhea and fever. But Vibrio vulnificus may enter the bloodstream, leading to septicemia or serious wound infections that sometimes result in amputations or death. An estimated 1 in 5 cases of Vibrio vulnificus infections are fatal, the CDC stated.
There are some 80,000 cases of vibriosis each year in the United States, and most people get vibriosis from eating raw or undercooked shellfish, particularly oysters, that have the bacteria, according to the Centers for Disease Control and Prevention.
Raw oysters also can spread viruses such as hepatitis A and norovirus, the notorious and highly contagious stomach bug.
The Food and Drug Administration requires seafood processors, including oyster processors, to follow Seafood Hazard Analysis and Critical Control Point regulations. They mandate that processors identify and control hazards. Additionally, under the federal-state National Shellfish Sanitation Program, oyster beds are routinely tested, and only certified suppliers can harvest, handle and store oysters from approved waters.
State and local agencies regulate restaurants where oysters are sold, experts said.
But it is not possible to test every oyster, and there is no way to tell by sight, smell or taste whether an oyster is carrying disease or whether a person will get sick from it, experts said.
Moreover, season and other factors are not reliable predictors. While Vibrio vulnificus, for instance, is more common in coastal waters during warmer months, the adage that people should eat raw oysters only in months that end in R – or cold-weather months in North America – is “a myth” as oysters may be harvested and imported from warmer waters, Chapman said.
“It’s not fail-safe because we import oysters from all over the place,” he said. “Raw oysters are a risky food regardless of the time of year.” Because of climate change-related increases in coastal water temperatures, Vibrio is becoming more common. (People can also get infected by swallowing water or through an open wound while swimming in a contaminated area.)
The most reliable way to eliminate pathogens is to cook the oysters. Many recipes call for steamed, grilled or roasted oysters, oftentimes cooking them in butter, herbs or seasonings. “Cooking will inactivate these harmful microorganisms very readily,” said Keith Schneider, a professor in food science and human nutrition at the University of Florida.
People who want to consume them raw may consider oysters that have undergone high-pressure processing in which the oysters are exposed to cold water and high pressure to help reduce Vibrio while keeping the raw texture, said Razieh Farzad, an assistant professor and a seafood safety extension specialist at the University of Florida. But, she said, only some processors use the technology, and that information may not be easily accessible for consumers.
Many experts suggest that people who are at higher risk, including older people and those who are immunocompromised, have liver disease, diabetes or are pregnant, should consider avoiding raw oysters. But experts are not necessarily against the delicacy for those who are not at increased risk.
“As long as people have the information and they are aware of the risks with choices they’re making, I think that’s a good place for us to be,” Chapman said.
What else you should know
Oysters are rich in essential micronutrients, including copper, iron, vitamin B12, and contain more zinc per serving than any other food, said Alison Kane, a registered dietitian at Massachusetts General Hospital.
While most minerals are retained during the cooking process, some nutrients may be lost at high temperatures, particularly when frying, which also adds extra calories and fat from the oils or batter, she said.
But grilling and steaming “are gentler cooking methods that don’t introduce additional fats or sodium and retain most of oysters’ nutrient density,” Kane added.
The bottom line: While many people enjoy raw oysters, the mollusks carry higher risks than many other foods and should be avoided by those who are more susceptible to potential infection. There are methods for mitigating risk,, but the most reliable way to kill pathogens is to cook the oysters.
torontosun.com
Author of the article:Washington Post
Washington Post
Lindsey Bever
Published Sep 10, 2025 • 4 minute read
Join the conversation
raw oysters
Raw oysters
Is it true that raw oysters are dangerous?
Many raw dishes such as steak tartare and sushi carry a risk of illness.
But raw oysters “are among the riskiest foods that we consume regularly,” said Benjamin Chapman, the department head of agricultural and human sciences at North Carolina State University.
In recent months, multiple states have reported cases of a deadly flesh-eating form of a bacteria that, in rare cases, can be spread by raw oysters. Vibrio vulnificus – which is usually spread through open wounds in contaminated seawater, but in an estimated 10 percent of cases can come from eating raw or undercooked shellfish – has led to at least five deaths in Florida and four in Louisiana, state health officials said.
Oysters and other mollusks such as clams and mussels live in coastal waters that contain bacteria, viruses and other contaminants. Some oysters may carry these pathogens, including the bacterium Vibrio that causes an infection called vibriosis.
Both Vibrio parahaemolyticus and Vibrio vulnificus can cause nausea, vomiting, diarrhea and fever. But Vibrio vulnificus may enter the bloodstream, leading to septicemia or serious wound infections that sometimes result in amputations or death. An estimated 1 in 5 cases of Vibrio vulnificus infections are fatal, the CDC stated.
There are some 80,000 cases of vibriosis each year in the United States, and most people get vibriosis from eating raw or undercooked shellfish, particularly oysters, that have the bacteria, according to the Centers for Disease Control and Prevention.
Raw oysters also can spread viruses such as hepatitis A and norovirus, the notorious and highly contagious stomach bug.
The Food and Drug Administration requires seafood processors, including oyster processors, to follow Seafood Hazard Analysis and Critical Control Point regulations. They mandate that processors identify and control hazards. Additionally, under the federal-state National Shellfish Sanitation Program, oyster beds are routinely tested, and only certified suppliers can harvest, handle and store oysters from approved waters.
State and local agencies regulate restaurants where oysters are sold, experts said.
But it is not possible to test every oyster, and there is no way to tell by sight, smell or taste whether an oyster is carrying disease or whether a person will get sick from it, experts said.
Moreover, season and other factors are not reliable predictors. While Vibrio vulnificus, for instance, is more common in coastal waters during warmer months, the adage that people should eat raw oysters only in months that end in R – or cold-weather months in North America – is “a myth” as oysters may be harvested and imported from warmer waters, Chapman said.
“It’s not fail-safe because we import oysters from all over the place,” he said. “Raw oysters are a risky food regardless of the time of year.” Because of climate change-related increases in coastal water temperatures, Vibrio is becoming more common. (People can also get infected by swallowing water or through an open wound while swimming in a contaminated area.)
The most reliable way to eliminate pathogens is to cook the oysters. Many recipes call for steamed, grilled or roasted oysters, oftentimes cooking them in butter, herbs or seasonings. “Cooking will inactivate these harmful microorganisms very readily,” said Keith Schneider, a professor in food science and human nutrition at the University of Florida.
People who want to consume them raw may consider oysters that have undergone high-pressure processing in which the oysters are exposed to cold water and high pressure to help reduce Vibrio while keeping the raw texture, said Razieh Farzad, an assistant professor and a seafood safety extension specialist at the University of Florida. But, she said, only some processors use the technology, and that information may not be easily accessible for consumers.
Many experts suggest that people who are at higher risk, including older people and those who are immunocompromised, have liver disease, diabetes or are pregnant, should consider avoiding raw oysters. But experts are not necessarily against the delicacy for those who are not at increased risk.
“As long as people have the information and they are aware of the risks with choices they’re making, I think that’s a good place for us to be,” Chapman said.
What else you should know
Oysters are rich in essential micronutrients, including copper, iron, vitamin B12, and contain more zinc per serving than any other food, said Alison Kane, a registered dietitian at Massachusetts General Hospital.
While most minerals are retained during the cooking process, some nutrients may be lost at high temperatures, particularly when frying, which also adds extra calories and fat from the oils or batter, she said.
But grilling and steaming “are gentler cooking methods that don’t introduce additional fats or sodium and retain most of oysters’ nutrient density,” Kane added.
The bottom line: While many people enjoy raw oysters, the mollusks carry higher risks than many other foods and should be avoided by those who are more susceptible to potential infection. There are methods for mitigating risk,, but the most reliable way to kill pathogens is to cook the oysters.
What to know about raw oysters and flesh-eating bacteria
Is it true that raw oysters are dangerous?
Oldest known lizard ancestor discovered in England
Author of the article:AFP
AFP
Published Sep 10, 2025 • Last updated 1 day ago • 2 minute read
New Zealand's tuatara reptile, which bears some striking similarities to the lizard ancestor discovered in England. Photo by Marty MELVILLE /POOL/AFP/File
Paris (AFP) — Scientists announced Wednesday they have discovered the oldest-known member of the lizard family in southwest England, a tiny creature that used its surprisingly large teeth to hunt cockroaches 242 million years ago.
The ancient reptile, which lived during the Middle Triassic epoch shortly before the rise of the dinosaurs, was so small its entire body could fit in the palm of a human hand.
“The new animal is unlike anything yet discovered and has made us all think again about the evolution of the lizard, snakes and the tuatara,” the latter of which is a New Zealand reptile, Dan Marke of the University of Bristol said in a statement.
The skeleton of the oldest known member of the lepidosauria order, a family of reptiles, was found at a fossil-rich beach in Devon, southwest England, in 2015.
But figuring out what it actually was took the scientists years, and the discovery was announced in a study in the journal Nature on Wednesday.
“The new fossil shows almost none of what we expected,” said Marke, the study’s lead author.
Modern lizards and snakes have a partially hinged skull and plenty of teeth on the roof of their mouth — but this ancient ancestor had neither.
“Not only this but it possesses some spectacularly large teeth compared to its closest relatives,” the palaeobiologist said.
It also has a bone running from cheek to jaw, a feature it shares only with the unique tuatara that is often referred to as a “living fossil”.
“The new beast” used these teeth “to pierce and shear the hard cuticles of its insect prey, pretty much as the tuatara does today,” said study co-author Michael Benton, also from Bristol University.
The fossil was difficult to study because it is so small — the skull is just 1.5 centimetres (0.6 of an inch) wide — and was preserved in a large rock.
So the British researchers scanned it using the European Synchrotron Radiation Facility, which works as a kind of huge microscope producing X-rays 100 billion times brighter than those used in hospitals.
The Synchrotron allowed the scientists to “zoom in on large objects and obtain very high-resolution images,” said Vincent Fernandez, a palaeontologist at the facility in France.
The scientists named the lizard ancestor Agriodontosaurus helsbypetrae, after the Helsby Sandstone Formation where it was discovered.
torontosun.com
Author of the article:AFP
AFP
Published Sep 10, 2025 • Last updated 1 day ago • 2 minute read
New Zealand's tuatara reptile, which bears some striking similarities to the lizard ancestor discovered in England. Photo by Marty MELVILLE /POOL/AFP/File
Paris (AFP) — Scientists announced Wednesday they have discovered the oldest-known member of the lizard family in southwest England, a tiny creature that used its surprisingly large teeth to hunt cockroaches 242 million years ago.
The ancient reptile, which lived during the Middle Triassic epoch shortly before the rise of the dinosaurs, was so small its entire body could fit in the palm of a human hand.
“The new animal is unlike anything yet discovered and has made us all think again about the evolution of the lizard, snakes and the tuatara,” the latter of which is a New Zealand reptile, Dan Marke of the University of Bristol said in a statement.
The skeleton of the oldest known member of the lepidosauria order, a family of reptiles, was found at a fossil-rich beach in Devon, southwest England, in 2015.
But figuring out what it actually was took the scientists years, and the discovery was announced in a study in the journal Nature on Wednesday.
“The new fossil shows almost none of what we expected,” said Marke, the study’s lead author.
Modern lizards and snakes have a partially hinged skull and plenty of teeth on the roof of their mouth — but this ancient ancestor had neither.
“Not only this but it possesses some spectacularly large teeth compared to its closest relatives,” the palaeobiologist said.
It also has a bone running from cheek to jaw, a feature it shares only with the unique tuatara that is often referred to as a “living fossil”.
“The new beast” used these teeth “to pierce and shear the hard cuticles of its insect prey, pretty much as the tuatara does today,” said study co-author Michael Benton, also from Bristol University.
The fossil was difficult to study because it is so small — the skull is just 1.5 centimetres (0.6 of an inch) wide — and was preserved in a large rock.
So the British researchers scanned it using the European Synchrotron Radiation Facility, which works as a kind of huge microscope producing X-rays 100 billion times brighter than those used in hospitals.
The Synchrotron allowed the scientists to “zoom in on large objects and obtain very high-resolution images,” said Vincent Fernandez, a palaeontologist at the facility in France.
The scientists named the lizard ancestor Agriodontosaurus helsbypetrae, after the Helsby Sandstone Formation where it was discovered.
Oldest known lizard ancestor discovered in England
The ancient reptile was so small its entire body could fit in the palm of a human hand.
For a lizard to survive 242 Million years of "Climate Change" in England is absolutely remarkable.