In the current study, published last month in Applied and Environmental Microbiology, researchers analyzed the genetic sequences of 1,077 samples of noroviruses found in oysters. Some sequences had been stockpiled in genetic databases since 1983.
The scientists found that 80 percent of the known human noroviruses matched those found in oysters. The majority of the matches were in oysters from coastal waters, more likely to be contaminated with human sewage.
Noroviruses mutate very quickly, as do influenza viruses, and big outbreaks usually begin after a new strain emerges. There was a “convergence” between new strains circulating in oysters and those circulating in humans, the researchers also found.
Yongjie Wang, a food science specialist at Shanghai Ocean University and lead author of the study, concluded that oysters were an important reservoir for human noroviruses — a place where they can hide between outbreaks and mutate. They also can be transmitted back to humans, presumably when oysters are eaten raw.
The restaurant, in conformance with its own corporate policy, voluntarily closed the facility, threw out all remaining food products, cleaned and disinfected the facility including all food contact surfaces, and excluded all employees with symptoms from working in the restaurant. EHD staff conducted an inspection the following day to confirm that the food had been removed, the restaurant was adequately disinfected, and the 18 employees had been excluded from work.
As part of the investigation the EHD and Public Health staff interviewed affected customers and restaurant staff to determine when the illness began and what had been eaten. The EHD also ordered that all affected restaurant employees submit specimens for laboratory analysis in an attempt to determine the cause of the illnesses. As of Sep. 3, 2015, 7-out-of-18 samples tested positive for Norovirus. The employees with positive test results will continue to be excluded from the restaurant until subsequent laboratory analysis results are negative for the virus and the Public Health Division has cleared them to return to work. There have been no further reports of illness since the initial reports two weeks ago.
CBS is reporting that almost 700 students, about 14% of the district, missed school today due to gastro illnesses that appear to be from norovirus, according to CBS News.
Superintendent Danny Holloman said there were 668 absences in the district Thursday, or 14 percent of the student population. Most of the absences came from Person High School, where more than 300 students stayed home.
Holloman said it’s not known how many students are actually sick and how many stayed home as a precaution.
CBS Raleigh affiliate WRAL reports Holloman realized something was going around just before lunch time yesterday, when large numbers of students were going home sick.
According to the Person County Health Department, a local doctor’s office experienced a similar situation with several patients and staff members coming down with virus-like symptoms last week. The North Carolina Division of Public Health asked that samples be collected from students to use for testing. The samples will be tested for both norovirus and other enteric pathogens, officials said.
Sick kids can spread gastrointestinal viruses around pretty quickly. I write from experience, my kids have brought home what was likely norovirus a couple of times from school/preschool and spread it to Dani and I.
Once the perfect human pathogen is in a restaurant, grocery store, or cruise ship – or school – it’s tough to get it out without some illnesses.
Part of the problem with noro (beyond the low mean infectious dose; environmental stability; and, 10^9 virus particles per gram of vomit/poop) is a vomit event can lead to particles floating through the air. And maybe moving 30 feet from the barf splatter.
According to ABC 11, over 100 students in Person County, NC are suffering from something that looks like norovirus.
Person County Schools says more than 100 students were sent home from school Wednesday due to illness.
The problem appeared to be come kind of virus that caused stomach problems.
Sources said 84 students and 6 teachers from Person County High School and 17 students from Helena Elementary School in the Timberlake area went home.
Managing a norovirus outbreak is a bit tricky, here are a couple of infosheets we’ve used/developed over the years that might be of use.
More than 80 percent of human norovirus genotypes were detected in oyster samples or oyster-related outbreaks,” said corresponding author Yongjie Wang, PhD.
“The results highlight oysters’ important role in the persistence of norovirus in the environment, and its transmission to humans, and they demonstrate the need for surveillance of human norovirus in oyster samples,” said Wang, who is Professor in the College of Food Science and Technology, Shanghai Ocean University, Shanghai, China.
In the study, the investigators downloaded all oyster-related norovirus sequences deposited during 1983-2014 into the National Center for Biotechnology’s GenBank database, and into the Noronet outbreak database. They conducted genotyping and phylogenic analyses, and mapped the norovirus’s genetic diversity and geographic distribution over time.
In earlier research, the investigators found that 90 percent of human norovirus sequences in China came from coastal regions. The current research showed that the same is true all over the world, except in tropical regions, from which sequences are absent.
Oysters’s status as reservoirs and vectors for human norovirus transmission is likely abetted by their presence in coastal waters, which are frequently contaminated by human waste, said Wang. Previous research suggests that noroviruses can persist for weeks in oyster tissues, and commercial depuration fails to expunge them.
Norovirus causes stomach pain, diarrhea, nausea, and vomiting. It is extremely contagious, and infects more than 6 percent of the US population, annually, resulting in around 20 million cases, including 56,000-71,000 hospitalizations and 570-800 deaths, according to the Centers for Disease Control and Prevention. Even touching a contaminated surface can result in infection.
Wang advised that people who eat oysters and other shellfish should eat them fully cooked, and never raw. He also urged development of a reliable method for detecting noroviruses in oysters, and a worldwide oyster-related norovirus outbreak surveillance network.
Brisbane is equidistant from the equator as Sarasota, Florida, and we have fabulous citrus.
Lemon-lime-and-bitters has become my go-to drink, along with the bubbly water provided by our soda stream.
But will lemon juice reduce my risk of contracting Norovirus?
Maybe.
Researchers at the German Cancer Research Center say that lemon juice could be a potentially safe and practical disinfectant against Norovirus.
I wouldn’t rely on it.
Human noroviruses does not grow in cell culture, so they tested the effects of increasing concentrations of citric buffer on the so called norovirus virus-like particles, which have the same surface characteristics as real viruses. Dr Grant Hansman, head of CHS junior research group at the German Cancer Research Center noroviruses and the University of Heidelberg and his staff show that the virus particles change their shape after citrate binding. X-ray crystal structures revealed that the citrate – from lemon juice or citrate disinfectants – precisely interacts at the binding pocket on the particle that is involved in attaching to host ligands – the so-called histo-blood group antigens.
These new results may explain why citrate reduces the infectivity of noroviruses. “Maybe a few drops of lemon juice on contaminated food or surfaces may prevent the transmission of these viruses,” speculates Hansman. With his staff, he now plans to investigate if citric acid could reduce symptoms in those already infected with noroviruses.
That’s a lot of maybes.
Anna D. Koromyslova, Peter White, and Grant S. Hansman: Citrate alters norovirus particle morphology. Virology 2015, DOI: 10.1016/j.virol.2015.07.009
The Daily Mail delivers what those in the biz call a BJ-piece in a fawning portrait of Heston Blumenthal, whose new menu will take diners on a ‘story-telling’ journey aimed at capturing childhood feelings of adventure when the new menu at his Fat Duck restaurant launches next month.
He has even turned to magician Derren Brown for tips on how to personalise people’s dinner choices by using auto-suggestion techniques so that diners get what they think they most crave.
Get the food safety right first, then indulge yourself with magic.
He also acknowledged that having more than 70 staff make handmade food for 40 seats at each service would likely force up the price of a meal.
I’ve been lucky to be close to some excellent projects, some of the stuff and knowledge created through these projects ends up mattering to food safety nerds – especially those who are making risk management decisions. NC State student Grace Tung-Thompson’s PhD project on vomit spray and norovirus is one of the most impactful. The work was carried out as part of the USDA NIFA-funded NoroCORE project led by my friend Lee-Ann Jaykus.
I’ve talked to lots of Environmental Health Specialists, retailers and food service food safety folks about what Grace and fellow graduate student Dominic Libera put together and many respond with a weird level of enthusiasm for the barf project.
Mainly because a real question they struggle with is how far will virus particles travel from an up-chuck event – knowing this, and then cleaning and sanitizing helps limit the scope of a potential outbreak. Today Grace’s work was published in PLOS ONE.
Matt Shipman, Research Communications Lead for University Communications and all around great guy writes about the project for The Abstract:
Tucked away in a quiet lab on NC State’s Raleigh campus is something that looks like a glorified air compressor with a grotesque clay face. It’s called “the vomiting machine” and it does exactly what you think it does. Researchers are using it to study one of the most widespread pathogens in the United States: norovirus.
Norovirus is a group of more than 30 related viruses that can cause vomiting and diarrhea. Norovirus affects about 20 million people each year in the U.S., with infections that can lead to hospitalization and occasionally to death, particularly in the elderly. About a quarter of the time, “noro” infection is obtained by consuming contaminated foods or water. However, it is most often spread between people in close contact with each other. The epidemic GII.4 strain predominates, but there are others.
But how, exactly, is noro transmitted from person to person?
“Epidemiological studies have suggested that norovirus can be ‘aerosolized’ through vomiting, meaning that small particles containing norovirus can become airborne when someone throws up,” says Grace Thompson, a recent Ph.D. graduate whose work at NC State focused on how norovirus spreads through vomiting and how long it is detectable in vomit. (Fun fact: noro can still be detected in dried vomit after six weeks.)
“According to outbreak reports, it appears that people can become infected with noro if they are directly or indirectly exposed to vomiting events,” Thompson explains. “If aerosolized particles land on a countertop, you could also touch the counter with your hand, then touch your hand to your mouth, leading to infection.”
But while norovirus aerosolization by vomiting has long been suspected, no one knew if it was actually occurring. This is the sort of question that Lee-Ann Jaykus’s lab lives for.
Jaykus is a professor of food science at NC State and scientific director of the U.S. Department of Agriculture-National Institute of Food and Agriculture Food Virology Collaborative, also known as NoroCORE (short for Norovirus Collaborative for Outreach, Research, and Education). They are, quite simply, norovirus experts.
To see if vomiting could really aerosolize norovirus, researchers in Jaykus’s lab (including Grace Thompson) needed a controlled way to observe and study vomiting over and over again. They needed a vomiting machine.
As you may imagine, there is a limited demand for vomiting machines, so the researchers had to design and build their own. They found a partner in Dominic Libera, a graduate student in NC State’s civil, construction and environmental engineering department in Francis de los Reyes’s lab. They also needed data upon which to build their model. Dr. Kenneth Koch, a gastroenterologist with Wake Forest University, provided that expertise.
Working together, the researchers created a machine that is essentially a scaled-down version of the mouth, esophagus, and stomach – made of tubes and a pressure chamber that passes through a clay face to give it the correct vomiting angle. The machine is designed (using engineering similitude principles) to let researchers control the pressure and volume of the vomit, in order to mimic a range of natural vomiting behaviors. The whole thing is enclosed in a sealed plexiglas box and placed under a biosafety hood. (A short video of the machine can be seen here.)
Instead of vomit, the researchers use liquid solutions of different viscosities or thicknesses as “artificial vomitus” to reflect different stages of digestion. And, since they cannot use real norovirus, they used a bacteriophage called MS2, which is a virus that infects E. coli but is harmless to humans. MS2 is easy to culture and is a common stand-in for noro.
Putting The Machine To Work
In 2012 and 2013, the team did extensive testing of the machine, to make sure that it was scaled appropriately and worked the way they wanted it to. And in 2014, Thompson began using the machine for formal experiments.
And what did they find? Well, virus was indeed aerosolized. Although the amount of MS2 aerosolized as a percent of total virus “vomited” was relatively low (less than 0.3 percent), vomit from infected people contains millions of particles. When the math is done, this means that the actual amount of virus particles aerosolized during a single vomiting event ranges from only a few into the thousands, perhaps more. (This work was recently published in PLOS ONE. More information on the findings is available here.)
“And that is enough to be problematic because it only takes a few, perhaps less than 20, to make a susceptible person ill” Jaykus says. “This machine may seem odd, but it’s helping us understand a disease that affects millions of people. This is work that can help us prevent or contain the spread of norovirus – and there’s nothing odd about that.”
Researchers report that the presence of norovirus in shellfish is a public health concern in Europe. Here, we report the results of an investigation into a norovirus gastroenteritis outbreak following a festive lunch which affected 84 (57%) residents and staff members of a nursing home in January 2012 in France. Individuals who had eaten oysters had a significantly higher risk of developing symptoms in the following 2·5 days than those who had not, the risk increasing with the amount eaten [relative risk 2·2 (1·0–4·6) and 3·3 (1·6–6·6) for 3–4 and 5–12 oysters, respectively].
In healthy individuals during those days, 29 (32%) subsequently became ill, most of whom were staff members performing activities in close contact with residents. Genogroup II noroviruses were detected in fecal samples, in a sample of uneaten oysters and in oysters from the production area. Identifying a norovirus’s infectious dose may facilitate the health-related management of contaminated shellfish.
A norovirus oyster-related outbreak in a nursing home in France, January 2012
Epidemiology and Infection / Volume 143 / Issue 12 / September 2015, pp 2486-2493
Loury, F. S. Le Guyader, J. C. Le Saux, K. Ambert-Balay, P. Parrot and B. Hubert
A few weeks ago a fellow food safety nerd and I sat on a Seattle train and watched a woman 20 ft away yack on the floor while her partner consoled her. My friend and I figured that we’d get noro just by being there (we didn’t).
A few years ago my son threw up on a flight which led to a fascinating approach by Delta Airlines involving plastic bags to contain the risk and coffee pods to manage the smell.
According to BBC, a Rynair passenger was forced to sit next to a vomit pile on a flight from Gatwick to London this week.
A 24-year-old was forced to sit in the same aisle as vomit left by a previous passenger on a Ryanair flight from Gatwick to Dublin on Sunday.
Noel O’Hare noticed the smell and mess as soon as he sat down with his friends on the hour and a half flight.
He told Newsbeat the “unsightly mess” was on the ground mixed in with a bag and tissues.
Ryanair cabin staff told him that because Gatwick isn’t their base and their cleaners are in Dublin, it couldn’t be cleaned up until they arrived back in Ireland.
Spray and aerosolization of vomit particles makes being in that adjacent seat particularly fun.
In the current study, published last month in Applied and Environmental Microbiology, researchers analyzed the genetic sequences of 1,077 samples of noroviruses found in oysters. Some sequences had been stockpiled in genetic databases since 1983.
