Doug Powell

About Doug Powell

A former professor of food safety and the publisher of barfblog.com, Powell is passionate about food, has five daughters, and is an OK goaltender in pickup hockey. Download Doug’s CV here. Download C.V. »

Foodborne disease outbreaks in the United States: A historical overview

Understanding the epidemiology of foodborne disease outbreaks (FBDOs) is important for informing investigation, control, and prevention methods.

We examined annual summary FBDO data in the United States from 1938 to 2015, to help understand the epidemiology of outbreaks over time. Due to changes in reporting procedures, before 1998, the mean number of annual outbreaks was 378, and after that, it was 1062.

A mean of 42% had a known etiology during 1961–1998; since then the etiology has been identified in ∼65%, with a marked increase in the number of norovirus outbreaks. From 1967 to 1997, a mean of 41% of FBDOs occurred in restaurant settings, increasing to 60% in 1998–2015. Concurrently, the proportion of outbreaks occurring at a home decreased from 25% to 8%.

The mean size of outbreaks has decreased over time, and the number of multistate outbreaks has increased. Many social, economic, environmental, technological, and regulatory changes have dramatically affected the epidemiology of foodborne disease over time.

Foodborne Pathogens and Disease, Vol. 15 Issue 1

January 2018

Timothy Jones and Jane Yackley

https://doi.org/10.1089/fpd.2017.2388

http://online.liebertpub.com/doi/abs/10.1089/fpd.2017.2388

Teens injesting laundry detergent in what’s dubbed the Tide pod challenge

CBS News reports that in this latest social media fad, teenagers are putting detergent pods in their mouths in what’s being called the “Tide Pod Challenge.”

Ingredients in the pods include ethanol, hydrogen peroxide and polymers – a highly-toxic mix of detergent meant to wipe out dirt and grime. Manufacturers have been concerned about toddlers mistakenly ingesting them, but now teens are popping them on purpose and posting videos of the results online, reports CBS News correspondent Anna Werner.

Nineteen-year-old Marc Pagan, who did it on a dare, told CBS News he knew better but did it anyway.

“A lot of people were just saying how stupid I was or how – why would I be willing to do that,” he said. “No one should be putting anything like that in their mouths, you know?”

Ann Marie Buerkle, acting chairman of the Consumer Product Safety Commission, says ingesting any of the liquid carries a deadly risk.

“This is what started out as a joke on the internet and now it’s just gone too far,” Buerkle said.

The pods are bright and colorful and to children they can look like candy. At least 10 deaths have been linked to ingesting these pods. Two were toddlers, eight were seniors with dementia.

Procter & Gamble, the maker of Tide products, told CBS News: “They should not be played with… Even if meant as a joke. Safety is no laughing matter.”

More than 62,000 children under the age of six were exposed to laundry and dishwasher detergents, between 2013 and 2014.

The next year, Consumer Reports said it would no longer recommend detergent packets, citing “the unique risks” while urging the “adoption of tougher safety measures.”

“Laundry detergent pods are highly concentrated detergent,” says Tammy Noble, a registered nurse and spokeswoman for the Iowa Poison Control Center. “Biting into them can cause diarrhea, some vomiting and sometimes that vomiting can even go on and on, excessive vomiting where we worry about it leading into dehydration.” Even if it’s being done as a joke and the person never intends to swallow the detergent, biting into the pod will likely make it squirt right down their gullet.

“It can cause burns in the mouth, the throat and the stomach,” Noble says. “Or there’s been cases where it accidentally gets into the lungs, where they aspirate it. That can cause significant breathing problems and sometimes that patient needs to be put on a ventilator to help them breathe.”

Modeling to reduce risks of Salmonella in alfalfa sprouts

We developed a risk assessment of human salmonellosis associated with consumption of alfalfa sprouts in the United States to evaluate the public health impact of applying treatments to seeds (0–5-log10 reduction in Salmonella) and testing spent irrigation water (SIW) during production.

The risk model considered variability and uncertainty in Salmonella contamination in seeds, Salmonella growth and spread during sprout production, sprout consumption, and Salmonella dose response.

Based on an estimated prevalence of 2.35% for 6.8 kg seed batches and without interventions, the model predicted 76,600 (95% confidence interval (CI) 15,400–248,000) cases/year. Risk reduction (by 5- to 7-fold) predicted from a 1-log10 seed treatment alone was comparable to SIW testing alone, and each additional 1-log10 seed treatment was predicted to provide a greater risk reduction than SIW testing. A 3-log10 or a 5-log10 seed treatment reduced the predicted cases/year to 139 (95% CI 33–448) or 1.4 (95% CI <1–4.5), respectively. Combined with SIW testing, a 3-log10 or 5-log10 seed treatment reduced the cases/year to 45 (95% CI 10–146) or <1 (95% CI <1–1.5), respectively. If the SIW coverage was less complete (i.e., less representative), a smaller risk reduction was predicted, e.g., a combined 3-log10 seed treatment and SIW testing with 20% coverage resulted in an estimated 92 (95% CI 22–298) cases/year.

Analysis of alternative scenarios using different assumptions for key model inputs showed that the predicted relative risk reductions are robust. This risk assessment provides a comprehensive approach for evaluating the public health impact of various interventions in a sprout production system.

Risk assessment of salmonellosis from consumption of alfalfa sprouts and evaluation of the public health impact of sprout seed treatment and spent irrigation water testing

January 2018, Risk Analysis

Yuhuan Chen, Regis Pouillot, Sofia Farakos, Steven Duret, Judith Spungen, Tong-Jen Fu, Fazila Shakir, Patricia Homola, Sherri Dennis, Jane Van Doren

DOI: 10.1111/risa.12964

http://onlinelibrary.wiley.com/doi/10.1111/risa.12964/epdf

‘Disease from outer space’ States confront the spread of CWD in deer

In March, 1996, the UK government confirmed what had been known for years: bovine spongiform encephalopathy (or mad cow disease) was killing humans in the UK.

The various forms of transmissible encephalopathies have different names according to the species – scrapie in sheep, feline spongiform encephalopathy in cats, Creutzfeldt-Jacob disease in humans, chronic wasting disease in deer and elk.

But they’re all the same affliction, caused by infectious proteins, or prions.

I haven’t been following the CWD outbreak in deer, but it seems to be where BSE was about 1993: There’s this mysterious new disease no one ever thoughts would cross over to humans, but now, maybe?

Jim Robbins of the New York Times writes that, as darkness closed in, one hunter after another stopped at this newly opened game check station, deer carcasses loaded in the beds of their pickups.

They had been given licenses for a special hunt, and others would follow. Jessica Goosmann, a wildlife technician with Montana’s Fish, Wildlife & Parks Department, stepped outside to greet them, reaching for the neck of each freshly killed deer to cut an incision and remove a lymph node for testing.

On the edge of this south-central Montana village, where deer hunting is a way of life, the game check station has become the front line of the state’s efforts to stop the spread of a deadly infection known as chronic wasting disease.

It has ravaged deer herds throughout the United States and Canada and forced the killing of thousands of infected animals in 24 states and three Canadian provinces. It has also been found in Norway and South Korea. With the disease widespread in Wyoming, the Dakotas and the province of Alberta, Montana officials had been bracing for its emergence.

So in November, when biologists discovered it in six deer in this part of Montana and in another near the Canadian border, officials began setting up special hunts and stations for testing.

“It wasn’t a surprise that we found it,” said John Vore, game management bureau chief for the Montana Department of Fish, Wildlife & Parks. “It was a disappointment, but not a surprise.”

On Friday, the department announced that two more deer from this region, taken early in the special hunt, tested positive for the disease. Other test results are pending.

Chronic wasting disease is a contagious neurological disease that infects elk, deer, moose and caribou, and reduces their brains to a spongy consistency. Animals become emaciated, behave strangely and eventually die. It’s not known to be transferred to humans. Neither is it known to be spread from wild to domestic animals. There is no treatment, although a vaccine has been successful in tests in wild deer.

It is among a class of diseases known as transmissible spongiform encephalopathy, or TSE. Most experts believe the infectious agent is something called a prion, a misfolded cellular protein found in the nervous system and lymph tissue. The disease was first noted in captive deer in Colorado in the 1960s. The most closely related animal disease is scrapie in sheep.

“It’s a very unusual disease,” said Matthew Dunfee, an expert at the Wildlife Management Institute in Fort Collins, Co. and project director for the Chronic Wasting Disease Alliance. “Some experts say it’s a disease from outer space.”

 

Black death: Plague was spread by people, not rats, and controlled by basic sanitation

Between 1340 and 1400, the Black Death spread throughout Europe, killing more than 20 million people. For hundreds of years, it was thought that fleas carried by black rats spread the deadly disease. But new research suggests that the “vermin” might not be to blame.

Kristin Hugo of Newsweek reportsstudy published in the Proceedings of the National Academy of Sciences on Monday illustrates how the plague might have spread. Researchers at the University of Oslo ran computerized mathematical simulations of disease spread by human-to-human fleas and lice, by human-to-rat-to-human fleas, and by airborne pathogens.

The researchers compared those computerized simulations to nine examples of the actual spread of the Black Death. They found that the simulations of human-to-human models most closely resembled the actual spread patterns in the nine real studies that they investigated, indicating that rats might not have been involved at all.

A study published in 2011 supports this conclusion. Authors say that the spread of the plague was too fast for rats to have been an intermediary, and furthermore, researchers should have found more dead rats that had succumbed if they were such important disease-carriers.

Another study in 2015 criticized the idea of rats as reservoirs of disease, claiming that the weather was too cold and rainy for rats to thrive and spread the disease widely. And an ecological review in 1986 cited a general lack of evidence for rats as the carriers of the disease.

However, exonerating the rats is likely to prove controversial among historians, who believe that the bacteria must have at least come from rats, or some other animal carrying fleas, at some point. The researchers at Oslo admit that their computer simulations could use more data, according to National Geographic. The more data a program has, the more accurate simulations it can run. 

Notably, the Black Death lost its grip when people started improving sanitation and cleaning themselves regularly, and covering sewers.

Roundworm: The parasite on the playground

Amy, Sorenne and I were walking around Nouvea, New Caledonia this morning, and passed a sushi shop.

I said, no, I don’t eat raw fish, I’m not into worms.

If it’s frozen at sea it should control the worms, but that a long supply loop and I got enough problems.

Sorenne said, why would worms live inside us.

I started on an intro microbiology talk, but she soon became more interested in the next shop, despite my efforts to make it sound gross.

Maybe this story from today’s N.Y. Times by Laura Beil will help.

Millions of American children have been exposed to a parasite that could interfere with their breathing, liver function, eyesight and even intelligence. Yet few scientists have studied the infection in the United States, and most doctors are unaware of it.

The parasites, roundworms of the genus Toxocara, live in the intestines of cats and dogs, especially strays. Microscopic eggs from Toxocara are shed in the animals’ feces, contaminating yards, playgrounds and sandboxes.

These infectious particles cling to the hands of children playing outside. Once swallowed, the eggs soon hatch, releasing larvae that wriggle through the body and, evidence suggests, may even reach the brain, compromising learning and cognition.

The Centers for Disease Control and Prevention periodically tracks positive tests for Toxocara through the National Health and Nutrition Examination Survey. The latest report, published in September in the journal Clinical Infectious Diseases, estimated that about 5 percent of the United States population — or about 16 million people — carry Toxocara antibodies in their blood, a sign they have ingested the eggs.

But the risk is not evenly shared: Poor and minority populations are more often exposed. The rate among African Americans was almost 7 percent, according to the C.D.C. Among people living below the poverty line, the infection rate was 10 percent.

The odds of a positive test rise with age, but it’s unknown whether this reflects recent infections or simply an accumulation of antibodies from past encounters.

Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, calls Toxocara both one of the most common parasites in the country and arguably the most neglected.

“We know in some cases it is linked to lower intelligence and epilepsy,” he said. “So if you were to look at disadvantaged kids living in poverty who are also doing lower on tests of school performance, what percentage of that can be attributed to this worm?”

While much is still unknown, “there’s enough here to warrant doing a major study on a large number of children.”

At the moment, research into Toxocara among Americans is so lacking that the National Institutes of Health funding website lists no grants to study it. Even many of the most basic questions are unanswered, including how often ingested eggs progress to full-blown infection.

Among the country’s overlooked parasitic infections, “Toxocara is probably the one that affects the broadest range of people,” said Sue Montgomery, lead of the epidemiology team at the parasitic diseases branch of the C.D.C. “Dogs and cats are everywhere. Many of them may carry the parasites.”

Studies indicate that owned pets who receive regular veterinary care rarely carry Toxocara. Poorer neighborhoods bear a disproportionate share of strays. In one survey, 8,700 unowned dogs were said to be roaming parts of Dallas.

A survey of New York City playgrounds, presented at a medical conference last year, sampled 21 parks across the city. Toxocara eggs were found in nine parks. Three quarters of samples taken in the Bronx contained eggs in the larval stage, which are more infectious. No parks in Manhattan had eggs with larvae.

26 sick: Multistate outbreak of Salmonella infections linked to Coconut Tree brand frozen shredded coconut

The U.S. Centers for Disease Control (CDC), public health and regulatory officials in several states, and the U.S. Food and Drug Administration (FDA) are investigating a multistate outbreak of Salmonella infections.

As of January 12, 2018, 25 people infected with the outbreak strains of Salmonella I 4,[5],12:b:- (24 people) or Salmonella Newport (1 person) have been reported from 9 states. One more ill person infected with the outbreak strain of Salmonella I 4,[5],12:b:- has been reported from Canada.

WGS showed that isolates from people infected with Salmonella I 4,[5],12:b:- are closely related genetically. This close genetic relationship means that people in this outbreak are more likely to share a common source of infection.

Illnesses started on dates ranging from May 11, 2017 to November 4, 2017. Ill people range in age from 1 year to 82, with a median age of 19. Among ill people, 19 (76%) are male. Six people (24%) report being hospitalized. No deaths have been reported.

Epidemiologic, laboratory, and traceback evidence indicates that Coconut Tree Brand frozen Shredded Coconut is the likely source of this multistate outbreak. This investigation is ongoing.

In interviews, ill people answered questions about the foods they ate and other exposures in the week before they became ill. Ten (63%) of 16 people interviewed reported eating or maybe eating coconut. Of these 10 people, 8 (80%) reported having an Asian-style dessert drink that contained frozen shredded coconut.

Throughout the outbreak investigation, state and local health officials have collected different food items from restaurants where ill people consumed Asian-style dessert drinks. In November 2017, laboratory testing of a sample from coconut milk made in one restaurant in New York did not identify the outbreak strain of Salmonella I 4,[5],12:b:-, but did identify a strain of SalmonellaNewport. This sample was from coconut milk made with Coconut Tree Brand frozen Shredded Coconut, as well as other ingredients. WGS showed that the Salmonella Newport isolated from the coconut milk was closely related genetically to a Salmonella Newport isolate from an ill person from Massachusetts who had consumed an Asian-style dessert drink.

In December 2017, officials in Massachusetts collected food items from a restaurant where that ill person had consumed Asian-style dessert drinks. One sample from frozen shredded coconut identified a strain of Salmonella that was new to the PulseNet database and has not been linked to any illnesses. This sample was from an unopened package of Coconut Tree Brand Frozen Shredded Coconut. As a result, on January 3, 2018, Evershing International Trading Company recalled all Coconut Tree Brand Frozen Shredded Coconut. The recalled product was packaged in 16-ounce plastic bags.

Officials in Massachusetts returned to the restaurant and collected more Coconut Tree Brand frozen Shredded Coconut in January 2018. On January 12, laboratory testing confirmed that samples from that frozen shredded coconut identified the outbreak strain of Salmonella I 4,[5],12:b:-. Laboratory testing of other samples identified several types of Salmonella bacteria, including Salmonella Javiana, Salmonella Rissen, and Salmonella Thompson. These samples were from unopened packages of Coconut Tree Brand Frozen Shredded Coconut sold before January 3, 2018. CDC is reviewing the PulseNet database to determine if the other Salmonella isolates from the frozen shredded coconut are linked to any illnesses.

Frozen shredded coconut can last for several months if kept frozen and may still be in retail stores or in people’s homes. CDC recommends that retailers not sell, restaurants not serve, and consumers not eat recalled Coconut Tree Brand frozen Shredded Coconut.

Salmonella may have caused a massive Aztec epidemic, study finds

Rebecca Hersher of NPR reports that in 1545, people in the Mexican highlands starting dying in enormous numbers. People infected with the disease bled and vomited before they died. Many had red spots on their skin.

It was one of the most devastating epidemics in human history. The 1545 outbreak, and a second wave in 1576, killed an estimated 7 million to 17 million people and contributed to the destruction of the Aztec Empire.

But identifying the pathogen responsible for the carnage has been difficult for scientists because infectious diseases leave behind very little archaeological evidence.

“There have been different schools of thought on what this disease was. Could it have been plague? Could it have been typhoid fever? Could it have been a litany of other diseases?” says Kirsten Bos, a molecular paleopathologist at the Max Planck Institute in Germany, and an author of a new study published Monday in Nature Ecology and Evolution.

The study analyzes DNA from the teeth of 10 people who died during the epidemic and pinpoints a possible culprit: a type of salmonella that causes a deadly fever.

A new algorithm allowed Bos and her team to identify fragments of ancient salmonella DNA with extreme specificity.

“It was an analytical technique that was really the game-changer for us,” Bos explains. While scientists have been able to extract ancient DNA from bones and other tissue, until recently it was impossible to compare that extracted DNA to a wide variety of potential matches.

But a new computer program called MALT allowed them to do just that. “The major advancement was this algorithm,” Bos says. “It offers a method of analyzing many, many, many small DNA fragments that we get, and actually identifying, by species name, the bacteria that are represented.”

Bos and her team used MALT to match up the DNA fragments extracted from teeth of epidemic victims with a database of known pathogens. The program didn’t entire save them from mind-numbing work — at one point PhD student and study author Ashild Vagene had to go through the results of the program by hand.

In the end, they found evidence of the deadly Salmonella enterica Paratyphi C bacteria.

The study does not pinpoint the source of the bacteria, which is an area of great interest for biologists and archaeologists alike. The authors note that many epidemics of the period are believed to originate with European invaders who arrived in the region in the early part of the 16th century, but the new research doesn’t present biological evidence for or against that.

Salmonella enterica gemones from victims of a major sixteenth-century epidemic in Mexico

Nature Ecology and Evolution, Published online 15 January 2018, Åshild J. VågeneAlexander HerbigMichael G. CampanaNelly M. Robles GarcíaChristina WarinnerSusanna SabinMaria A. SpyrouAida Andrades ValtueñaDaniel HusonNoreen TurossKirsten I. Bos & Johannes Krause, doi:10.1038/s41559-017-0446-6

https://www.nature.com/articles/s41559-017-0446-6

Indigenous populations of the Americas experienced high mortality rates during the early contact period as a result of infectious diseases, many of which were introduced by Europeans. Most of the pathogenic agents that caused these outbreaks remain unknown.

Through the introduction of a new metagenomic analysis tool called MALT, applied here to search for traces of ancient pathogen DNA, we were able to identify Salmonella enterica in individuals buried in an early contact era epidemic cemetery at Teposcolula-Yucundaa, Oaxaca in southern Mexico. This cemetery is linked, based on historical and archaeological evidence, to the 1545–1550 CE epidemic that affected large parts of Mexico. Locally, this epidemic was known as ‘cocoliztli’, the pathogenic cause of which has been debated for more than a century.

Here, we present genome-wide data from ten individuals for Salmonella enterica subsp. enterica serovar Paratyphi C, a bacterial cause of enteric fever. We propose that S. Paratyphi C be considered a strong candidate for the epidemic population decline during the 1545 cocoliztli outbreak at Teposcolula-Yucundaa.

Madagascar: 10 deaths from sea turtle meat

Continuing with the French imperialism theme, after returning from fishing, villagers in the fokontany of Ambavarano, Mahavanona commune in Ansirtanana II shared sea turtle meat

Immediately after the meal, the first symptoms of food poisoning appeared. They did not stop vomiting and were later evacuated to the hospital.

And despite the intensive care that was provided to the sick, 10 people, including a one-year-old, baby, did not survive. According to the explanations, sea turtles were unfit for consumption.

Currently three other villagers are still receiving treatment at the hospital. Local officials conducted a public awareness campaign to prevent the incident from recurring.

 

Modeling foodborne illness effects in France, 2008-2013

Many thanks to our French correspondent who forwarded this abstract on the latest foodborne illness data from France.

To assess the impact of foodborne infections on human health and to set priorities for surveillance, prevention and control strategies, estimates of food-related morbidity and mortality are necessary. The objective of the present study was to produce the annual number of symptomatic cases, hospitalized cases and deceased cases for 21 foodborne pathogen agents (10 bacteria, 3 viruses, 8 parasites) in metropolitan France for the 2008-2013 period.

Our findings reveal that morbidity and mortality attributed to infectious foodborne diseases remain high in France, representing 1.28-2.23 million illnesses, 15,800-21,200 hospitalizations, and 232-358 deaths. Campylobacter spp., non-typhoidal Salmonella spp. and norovirus infections accounted for the majority of all food-related illnesses and hospitalizations in France. Non-typhoidal Salmonella spp. and Listeria monocytogenes accounted for half of the burden of food-related deaths.

The knowledge of the absolute and relative burden of food-borne infections is useful for all stakeholders (public authorities and operators) involved in the field of food safety.

Estimates of food-related morbidity and mortality in metropolitan France, 2008-2013

Bulletin epidemiologique hebdomadaire

Dieter Van Cauteren, Yann Le Strat, Cecile Sommen, Mathias Bruyand, Mathieu Tourdjman, Nathalie Jourdan-Da Silva, Elisaveth Couturier, Nelly Fournet, Henriette De Valk, Jean-Claude Desenclos

http://invs.santepubliquefrance.fr/beh/2018/1/2018_1_1.html