The Centre for Health Protection (CHP) of the Department of Health is investigating a suspected outbreak of food poisoning in a tour group, and hence urged the public to maintain good personal, food and environmental hygiene to prevent food-borne diseases.
Because all foodborne illness is caused by poor personal hygiene, and not contaminated product.
Not
The outbreak affected six members of the tour group, comprising two men and four women aged from 44 to 80, who developed abdominal pain, diarrhoea and vomiting 14 to 40 hours after their lunch buffet in a restaurant in a hotel in Macau on August 13 arranged by a travel agent in Hong Kong.
Among them, three sought medical attention in Hong Kong and required no hospitalisation. All affected persons have been in stable condition.
The stool specimen of one patient tested positive for Vibrio parahaemolyticus upon laboratory testing.
A foodborne illness outbreak linked to raw oysters has sickened at least 25 people who dined at local restaurants recently, King County reported on Tuesday. The news comes after the county reported last week that a handful of people got sick eating raw oysters at two Seattle restaurants – The Salted Sea and The White Swan Public House.
The restaurants, however, are not the source of the outbreak, King County says. Most likely, the oysters were mishandled or contaminated before reaching local restaurants, although no specific local oyster beds have been connected to the outbreak.
County health officials believe diners have been sickened by Vibrio, a marine bacteria commonly found in oysters.
“Eating undercooked or raw shellfish, especially raw oysters in warm-weather months, is the main risk for acquiring vibriosis from infection with Vibrio parahaemolyticus,” King County said.
That finding, from UT Southwestern Medical Center, was reported today in PLoS Pathogens. Without a working cytoskeleton, infected cells are unable to produce defensive molecules called reactive oxygen species (ROS) that normally attack bacterial DNA, said Dr. Marcela de Souza Santos, lead author of the study and a postdoctoral researcher in the laboratory of senior author Dr. Kim Orth. Dr. Orth is a Professor of Molecular Biology and Biochemistry at UT Southwestern as well as an Investigator in the prestigious Howard Hughes Medical Institute.
“Vibrio parahaemolyticus bacteria deploy a needlelike apparatus called a Type III Secretion System (T3SS) that injects toxic bacterial proteins, known as effectors, into cells that line the intestine, resulting in severe gastroenteritis,” Dr. de Souza Santos said.
Usually V. parahaemolyticus causes only a few days of gastrointestinal distress in the form of vomiting or diarrhea. On rare occasions, however, particularly in people with chronic health conditions like diabetes or liver disease that compromise the immune system, the bacteria can escape from the gut and enter the bloodstream, causing life-threatening systemic infection.
Of the nearly 80 known Vibrio strains, only about a dozen infect humans. The Centers for Disease Control and Prevention (CDC) estimates Vibrio cause 80,000 illnesses and 100 deaths in the U.S. annually. Of those, an estimated 45,000 people are sickened by V. parahaemolyticus. Another Vibrio strain, V. vulnificus, can cause life-threatening infections in people with open wounds exposed to warm seawater. As with other Vibrio strains, people who are immunocompromised are at highest risk.
“Vibrio parahaemolyticus is the reason for the old saying that you shouldn’t eat oysters in months without an ‘r’ in them, meaning the summer months,” said Dr. Orth, holder of the Earl A. Forsythe Chair in Biomedical Science and a W.W. Caruth, Jr. Scholar in Biomedical Research. “With the warming of the oceans, the risk now starts earlier in the year and the bacteria’s geographical range is spreading.” The CDC’s fact sheet says that 80 percent of U.S. vibriosis infections occur between May and October.
The state of Alaska reported its first V. parahaemolyticus outbreak in July 2004. Another strain of Vibrio sickened more than 80 people exposed to contaminated seawater during a heatwave in Northern Europe in 2014. The first Vibrio strains were identified in the 18th century.
Until recently, it was believed that Vibrio bacteria remained outside cells, doing their damage by shooting effectors into cells. However, in 2012, the Orth laboratory identified a way that V. parahaemolyticus tricks random cells lining the gut into engulfing the bacterium and bringing it inside the cell. The current study indicates how the T3SS protein VopL aids V. parahaemolyticus infection by helping the pathogen secure a niche within the cell for bacterial replication.
It’s a good strategy for a bacterium to infect random cells only, Dr. Orth said. If a pathogen were to infect most of the host’s cells quickly – as is thought to occur with the Ebola virus – the pathogen might kill its host so fast that it could undermine its own survival, she said.
In a study published last month in Science Signaling, the Orth laboratory did something unprecedented: It followed V. parahaemolyticus infection over time – flash freezing samples every 15 minutes – to chart the pathogen’s effect on host signaling. That study identified 398 genes whose expressions were changed by Vibrio infection, said lead author and postdoctoral researcher Dr. Nicole De Nisco.
In the current study, the researchers found that one of V. parahaemolyticus’ many effectors – VopL – paralyzes the cytoskeleton through a novel mechanism. The cellular machinery, or complex, that makes the ROS sits on the cell surface, but the molecules that the cellular factory needs to assemble ROS are created inside the cell. A working, flexible cytoskeleton is necessary to move the molecules to the ROS factory, she explained.
To confirm their observation, the researchers created two V. parahaemolyticus strains, one able to make VopL and another not. Using confocal microscopy, they found that the Vibrio able to produce VopL inactivated the assembly of ROS by gathering the cytoskeleton into nonfunctional filaments. In contrast, the mutant bacterium unable to produce VopL was vulnerable to ROS attack.
This study identifies the virulence factor used by V. parahaemolyticus to suppress host ROS generation and also reveals an unprecedented mechanism used by a microbial pathogen to do so, said Dr. Orth.
“By hijacking the cytoskeleton, VopL prevents the cell from launching one of its major weapons, reactive oxygen species,” said Dr. Orth. “We hope our work will lead to a better understanding of host defense, which, in turn could lead to new ways to undermine the pathogens.”
Ben Tinker of CNN reports a 31-year-old Texas man went to get a tattoo on his right leg. Beneath an illustration of a cross and hands in prayer, the words “Jesus is my life” were written in cursive.
As tattoo artists will tell you, there are some critically important rules to follow in the hours and days after getting inked. Most important: keeping your new body art clean and covered while the skin has a heightened susceptibility to bacterial infection.
Every time a tattoo gun pierces your skin, the needle is opening a wound — and another pathway by which germs can enter your body. The larger the tattoo, the more you increase your risk of possible infection.
A report published last week in BMJ Case Reports, a prominent peer-reviewed medical journal, reveals only that the subject was a Latino man living in Texas.
Five days after getting his tattoo, the man decided to go for a swim in the Gulf of Mexico. Just three days after that, he was admitted to Parkland Memorial Hospital in Dallas with severe pain in both of his legs and feet. His symptoms included a fever, chills and redness around his tattoo and elsewhere on his legs.
“A lot of our patients, when they come to our institution, come in sick — and he was certainly among the sicker of the patients that we’ve had come in,” said Dr. Nicholas Hendren, an internal medicine resident at University of Texas Southwestern Medical Center and lead author of the report. “He said he had a lot of pain in [his right leg]. That, of course, drew our attention right away.
“Within a few hours, things had progressed pretty quickly,” he said. “There’s darkening skin changes, more bruising, more discoloration, what we call bullae — or mounds of fluid that were starting to collect in his legs — which, of course, is very alarming to anyone, as it was to us.
“He was already in the early stages of septic shock, and his kidneys had already had some injury,” Hendren said. “Very quickly, his septic shock progressed from … early stages to severe stages very rapidly, within 12 hours or so, which is typical for this type of infection.”
To make matters worse, the man had chronic liver disease from drinking six 12-ounce beers a day. He was immediately placed on a ventilator to help him breathe and given potent antibiotics.
The man tested positive for Vibrio vulnificus, a bacterium commonly found in coastal ocean water. The CDC estimates that this infection, called vibriosis, causes 80,000 illnesses and 100 deaths every year in the United States. The strongest risk factors are liver disease, cancer, diabetes, HIV and thalassemia, a rare blood disorder.
“In the USA, most serious infections appear to occur with the ingestion of raw oysters along the Gulf Coast, as nearly all oysters are reported to harbor V. vulnificus during the summer months and 95% of cases were related to raw
Most of the time, the only symptoms someone will experience are vomiting and diarrhea, according to Hendren. Most healthy people don’t end up in the hospital, he said, because their immune system is strong enough to fight the infection.
But “Infections can also occur with exposure of open wounds to contaminated salt or brackish water; however, this represents an uncommon mechanism of infection,” according to the report.
Hendren never got the opportunity to ask the patient directly whether he was aware of the advice against swimming soon after getting a tattoo but said the man and his family were unaware of how a serious infection can progress so quickly.
For the next few weeks, the man was kept largely sedated. After initial pessimism about the man’s prognosis, Hendren and his colleagues became cautiously optimistic. The patient was removed from the breathing machine 18 days after being admitted to the hospital and began “aggressive rehabilitation.”
Over the next month, however, the man’s condition slowly began to worsen. About two months after he was first admitted to the hospital, he died of septic shock.
“For patients who are healthy, this organism very rarely infects people,” Hendren said. “If they are infected, most people do fine and essentially never present to the hospital. But in patients who do have liver disease, they’re susceptible to much more infection.”
Since most infections are the result of eating raw oysters, Hendren stressed the only way to kill the bacteria is by cooking them. People with liver disease or iron disorders should never eat raw oysters because they’re at such high risk for these infections, he said.
Hendren said the message isn’t that people shouldn’t get tattoos.
“It’s if you choose to get a tattoo, do it safely, do it through a licensed place, and make sure you take care of the wound and treat it like any other wound,” he said. “That’s important.”
Michael Casey of The Charlotte Observer reports that for the past 25 years, researcher Stephen Jones has tried to understand the threat that bacteria may pose to oysters in New Hampshire’s Great Bay estuary. He often couldn’t get funding to study the problem. But that is beginning to change as scientists notice “something is going on.”
“We have this situation in the northern part of the United States and other cooler climates where people haven’t thought this had been a problem,” said Jones, of the Northeast Center for Vibrio Disease and Ecology at the University of New Hampshire. “In the last 10 or 20 years, it’s become very apparent that there is something going on.”
In a paper in the science journal PLOS One, Jones and other scientists reported their findings that illnesses from vibrio bacteria have jumped significantly in New England — from five cases in 2000 to 147 in 2013. Disease-causing bacteria can contaminate oysters, leading to infections such as diarrhea, vomiting and abdominal pain.
Jones and his colleague, Cheryl Whistler, concluded that warmer waters in the Great Bay, higher salinity and the presence of chlorophyll all contributed to higher concentrations of one of the more common vibrio species that makes people sick — vibrio parahaemolyticus. The researchers are hoping their findings will serve as the foundation of an early warning system for the region’s booming oyster industry.
Currently, all experts can do is monitor the waters and rapidly cool harvested oyster to halt bacteria growth.
An August report in the Proceedings of the National Academy of Sciences found that warming waters were linked to waterborne food poisoning, especially from eating raw oysters.
“There is similar reporting in Alaska where it has been found that increased cases have been occurring where it has not been reported before because of the temperature rise,” said the study’s lead author, Rita Colwell, of the University of Maryland.
The industry has welcomed Jones and Whistler’s work, noting that outbreaks like the one that occurred last month in Massachusetts need to be avoided. Nearly 75 people were sickened.
“When you are involved with a recall because people have gotten sick, you are a losing tremendous amount of money and a tremendous amount of credibility,” said Tom Howell, president of Spinney Creek Shellfish Inc., in Eliot, Maine, which harvests oysters from the Great Bay. A predictive model would allow the industry to move more aggressively to avoid an outbreak, he said.
But Howell and Chris Nash, New Hampshire’s shellfish program manager, said that day could be far off.
“We are still learning what seems to trigger these pathogenic strains to multiply … We don’t have that knowledge yet and it may be that we never do,” Nash said. “We are talking about biological organisms … They react to their environment different, the same way humans do.”
Vernal Coleman of the Seattle Times reports that fish bought from a Bellevue supermarket is the likely source of a woman’s rare, life-threatening bacterial infection, according to health officials.
The woman was diagnosed with Vibrio vulnificus on Nov. 10, said officials with Public Health — Seattle & King County. Often found in contaminated seawater, the infection can cause symptoms ranging from vomiting and diarrhea to flesh-eating skin wounds.
Officials suspect the woman was infected after cutting her finger while preparing the fish. According to officials, the woman, who is in her 50s, bought the tilapia fish from the Asian Food Center, at 14509 N.E. 20th St. She was later hospitalized and has since returned home.
The supermarket’s fish stock was disposed of, while the tanks and other equipment used to process fish at the market were decommissioned until they can be cleaned and disinfected, officials said. Department investigators will work with the Food and Drug Administration to investigate any food and product distributors found to be the source of contaminated food, officials said.
Princeton researchers have for the first time revealed the mechanics of how bacteria build up slimy masses, called biofilms, cell by cell. When encased in biofilms in the human body, bacteria are a thousand times less susceptible to antibiotics, making certain infections, such as pneumonia, difficult to treat and potentially lethal.
In a study published Sept. 6 in the Proceedings of the National Academy of Sciences, a team at Princeton tracked a single bacterial cell as it grew into a mature biofilm of 10,000 cells with an ordered architecture. The findings should help scientists learn more about bacterial behavior and open up new ways of attacking biofilms with drugs.
“No one’s ever peered inside a living biofilm and watched it develop cell by cell,” said Bonnie Bassler, a senior author of the paper and the Squibb Professor in Molecular Biology at Princeton, as well as a Howard Hughes Medical Institute Investigator. “With this paper, we can now understand for the first time how communities of bacteria form a biofilm.”
The discovery became possible thanks to a special microscopy method pioneered at Princeton by a former postdoctoral research associate, Knut Drescher, which allowed the imaging of single cells, letting researchers follow a budding biofilm in real time.
“We have used a state-of-the-art technique to see into the core of a living, growing biofilm,” said postdoctoral research associate Jing Yan, lead author of the new study. Along with membership in Bassler’s lab, Yan belongs to the Complex Fluids Group led by paper senior co-author Howard Stone, the Donald R. Dixon ’69 and Elizabeth W. Dixon Professor of Mechanical and Aerospace Engineering at Princeton. Yan is further advised by paper senior author Ned Wingreen, the Howard A. Prior Professor of the Life Sciences and acting director of the Lewis-Sigler Institute for Integrative Genomics at Princeton.
“The research that produced this paper sits at the frontier between materials science, engineering, physics and biology and represents a fantastic collaboration across Princeton University,” said Bassler.
Along with Yan, Bassler, Stone and Wingreen, a fifth co-author of the paper is Andrew Sharo, a former undergraduate in Princeton’s Department of Physics and now at the University of California-Berkeley.
The researchers chose Vibrio cholerae for their model biofilm organism because of its long history of study and threat to human health, causing the diarrheal disease cholera. A curved, rod-shaped bacterium, V. cholerae lives as a free-swimming cell in brackish water or saltwater. When V. cholerae makes contact with a food particle, perhaps on the shell of a crab or a shrimp, or a human intestinal cell during disease, the bacterium attaches itself and begins to reproduce. The expanding colony’s members secrete a glue-like substance to keep from getting washed away and to protect themselves from competing bacteria.
Previous efforts to delve into how the cells in a burgeoning biofilm interact had failed because of insufficient optical resolution; basically, what one cell was doing in the opaque mass could not be distinguished from its neighbors.
The Princeton researchers overcame this problem in several ways. First, they genetically modified the bacterial strain so the cells produced proteins that glow brightly when illuminated by specific colors of light. The proteins selected offer the brightest available fluorescence, making each cell easier to pick out, while reducing the intensity of potentially cell-damaging light required for the experiment.
The team then used a confocal microscope, a device that focuses on a single portion of a specimen from a certain distance. By making hundreds of such observations, images can be stacked together to create a three-dimensional image of the entire specimen. “It’s like looking deep into the interior of a biofilm without having to slice it open,” said Yan.
Another boost for the research team came from computer algorithms originally developed for fields like materials science. The algorithms differentiated closely clustered sources of light, in this case the many bunched-up V. cholerae cells in a thickening biofilm.
What the Princeton team saw was remarkable. At first, the bacterial colony expanded horizontally on the given surface in the experiment. As each cell split, the resulting daughter cells firmly attached to the surface alongside their parent cells. Squeezed by increasing numbers of offspring bacteria, however, the cells at the heart of expanding colony were forced to detach from the surface and point vertically. The bacterial colony thus went from a flat, two-dimensional mass to an expanding, three-dimensional blob, all held together by gunk in the developing biofilm.
The Princeton team dug a bit deeper into the genetics behind this cellular behavior. A single gene, dubbed RbmA, is key to behavior in which new cells connect in such a way to develop a three-dimensional biofilm. When the researchers deactivated the gene, a big, diffuse and floppy biofilm formed. When RbmA performed as normal, though, a denser, stronger biofilm resulted as the cells stayed linked to each other. Thus, RbmA provides the biofilm its resilience, providing insight into a potential Achilles heel that could be targeted for therapeutic intervention.
Ongoing work is now measuring the physical forces experienced by cells uplifting at the biofilm’s center so the overall mechanics can be precisely worked out. “We are currently trying to develop a mathematical model for how the bacterial colony grows in time and how the spatial features are linked to typical mechanical features of the biofilm,” said Stone.
Knowing the survival characteristics of foodborne pathogens in raw ready-to-eat (RTE) seafood is the key to predicting whether they pose a microbiological hazard. The present study examined the survival of Escherichia coli O157:H7, Salmonella Typhimurium, Vibrio parahaemoliticus, Listeria monocytogenes, and Staphylococcus aure- us in raw RTE crab marinated in soy sauce.
Inoculated crabs (initial bacterial population = 4.1–4.4 log CFU/g) were immersed in soy sauce and then stored at refrigeration (5 °C) or room temperature (22 °C) for up to 28 days. At 5 °C, all bacteria (except V. parahaemolyticus) survived in crab samples until Day 28 (counts of 1.4, 1.6, 3.1, 3.2 log CFU/g for E. coli O157:H7, S. Typhimurium, L. monocytogenes, and S. aureus, respectively). Howev- er, at 22 °C, all tested bacteria were more susceptible to the antimicrobial effects of marination. Regardless of tem- perature, foodborne pathogens attached to crab samples were more resistant to marination than those suspended in soy sauce samples; however, the survival pattern for each species was different. Gram-positive bac- teria were most resistant to marination conditions (high salinity, low pH), whereas V. parahaemolyticus was ex- tremely susceptible.
Marination is the only antibacterial step in the manufacturing processes; however, the results presented herein reveal that this is not sufficient to inactivate foodborne pathogens. In particular, the survival of pathogens on crabs at refrigeration temperature may pose a major hazard for the consumption of raw RTE seafood. Thus, appropriate decontamination methods and implementation of safety management practices are needed.
This study provides predictive microbiological information of foodborne pathogens in raw RTE seafood with margination.
Survival of foodborne pathogens (Escherichia coli O157:H7, Salmonella Typhimurium, Staphylococcus aureus, Listeria monocytogenes, and Vibrio parahaemolyticus) in raw ready-to-eat crab marinated in soy sauce
International Journal of Food Microbiology 238 (2016) 50–55, DOI: http://dx.doi.org/10.1016/j.ijfoodmicro.2016.08.041
Jeremy Olson of the Star Tribune reports that city health inspectors in Minneapolis are investigating a summer increase in foodborne illnesses related to norovirus and Vibrio, a bacteria found in raw oysters.
The increases were highlighted in the city’s “food establishment” newsletter, released Thursday.
“The reason for the spike in norovirus outbreaks is not known,” the advisory stated. “The Vibrio outbreaks are due to higher concentrations of bacteria in some oyster beds during the summer.”
Cases of norovirus, a highly contagious bug that causes severe vomiting and diarrhea, are not required to be reported to the Minnesota Department of Health, but the state agency has received reports of a slight uptick that is unusual for this time of year.
Jacqueline Ingles of WFTS Tampa Bay reports, take a ride on Captain Nick Warhurst’s boat and there is just one rule: do not eat raw shellfish.
“I’d rather you not eat anything raw on my boat,” said Warhurst. “If you want to eat them raw you wait till you get to the dock and you’re on your own.”
Married to a nurse, Warhurst says he knows the dangers of eating raw or undercooked shellfish.
“Some people die from this stuff,” he explained.
According to the Florida Department of Health, two Bay area residents did get infected with Vibrio Vulnificus and died this year. One resident was from Citrus County, the other resided in Sarasota County.
Vibrio is a bacteria that occurs naturally in Gulf Coast waters.
You can also get infected if you go into water with an open cut or sore.
So far this year, 23 people have been infected by the bacteria across the states. A total of five people have died from the infections.
However, contracting it is rare.
“It is really, really, really rare, but why take the chance,” asked Terry Natwick, the director of sales and marketing at the Plantation Inn in Crystal River.
The inn, which is a hotspot for tourists who’ve come to scallop stay, offers a catch and cook program.
“Not only do we have somebody who will professionally shuck the scallops for you and keep it on ice and then put it in a Ziplock and then you bring it right to our kitchen where we refrigerate it at the proper temperature and cook if for you either that day at lunch or that night for dinner,” Natwick said.
First time scalloper Nick Tulse is taking the Inn up on it’s offer.
“Oh no no, you cook ’em,” said Tulse, who drove up from Bradenton.
Because all foodborne illness is caused by poor personal hygiene, and not contaminated product.
![Oyster-Vancouver, B.C.- 07/05/07- Joe Fortes Oyster Specialist Oyster Bob Skinner samples a Fanny Bay oyster at the restuarant. Vancouver Coastal Health now requires restaurants to inform their patrons of the dangers of eating raw shellfish. (Richard Lam/Vancouver Sun) [PNG Merlin Archive]](https://barfblog.com/wp-content/uploads/2016/12/raw.oyster.jpg)
