Paradise Parasites — Challenges To Controlling Rat Lungworm Disease

“Tropical parasites in our food? No way!” most Americans think.  Its time to think again.  In May Hawaii’s Department of Health announced three more cases of rat lungworm in recent visitors. Already endemic in Hawaii, Asia, Australia, Brazil and the Caribbean, the exotic foodborne menace is also emerging in Florida and other southeastern states.

Rat lungworm survives using clever, earthy tactics. Adult worms live in rats—snails and slugs get infected by eating rat droppings—rats get infected by eating parasite-laden snails and slugs. Humans are “dead-end hosts,” meaning we can’t transmit the disease to others. But we can still fall gravely ill when larvae migrate, grow and die in our brains.

Last year, ten people officially contracted rat lungworm in Hawaii, presumably from eating locally-grown greens harboring mollusks. But human cases are underreported, according to the state’s Department of Health. Consider the risk in fauna. In Hawaii, up to 70 percent of a newly-invasive semi-slug carry rat lungworm larvae… meanwhile a 2017 Florida study found the parasite in one in five rats and one in 50 snailsIn Florida, it has killed or sickened zoo animals; in neighboring states, it has also sickened a handful of humans.

What if plants grown in Hawaii or the Southeast spread infected mollusks to new locales? If tiny, larval-laden snails enter the Salinas Valley—especially if temperatures and rainfall continue to climb—could California’s leafy greens someday spawn cases? We believe the answer is yes.

The risk to tourists is equally worrisome. More than 9 million visit Hawaii every year and visitors have developed the disease. Returning travelers face many diagnostic obstacles, including the lack of definitive blood tests.

In the 1980s, one of us saw toddlers in Taiwan initially diagnosed with bacterial meningitis before unusual cells in their spinal fluid pointed to rat lungworm. Thirty years later, the situation hasn’t changed. Unless a doctor thinks of it, then performs a spinal tap, requests special tests and prescribes the right medications, patients can suffer dire harm.

More lessons can be gleaned from a landmark outbreak. In 1999, 23 medical students traveled to Jamaica on spring-break and shared a final celebratory feast. Weeks later, eleven of the twelve who ate Caesar salad tested positive for rat lungworm at the CDC. Three sufferers were well enough to remain outpatients, while a fellow student was hospitalized for weeks and—despite intravenous steroids—required a dozen spinal taps to relieve sky-high pressure in her brain.

Saddest of all is the story of Sam Ballard from Australia. In 2010, while in Sydney, the 19-year old ate a slug on a dare, thus contracting rat lungworm. After awakening from a coma, Ballard was fully paralyzed, and in 2018, he died. Hawaii has witnessed similar tragedies.

This P. martensi, the semi-slug, is not shown at actual size in this photograph. Big Island Invasive Species Committee

What can be done?
In Hawaii, especially near Hilo, a non-native semi-slug with high larval loads likely accounts for worsening infections. This small species with a toenail-sized shell on its back enters gardens, houses and water tanks. Controlling the semi-slug and other intermediate hosts is an uphill but necessary battle.

Physicians on the mainland still lack knowledge about rat lungworm disease. Education is needed, as are better diagnostic tests.

Education is also needed for visitors to Hawaii, Florida and other places where the parasite is present. Sensible advice? Eat only local produce that has been thoroughly washed. Don’t throw fresh leafy greens into a blender for a Kermit-colored smoothie. Don’t drink from a hose where a snail or slug might hide. Don’t let children play with snails!

Finally, what rat lungworm teaches is the dynamic ecology of foodborne parasites and one more basic truth. Parasites are not just “over there” — but here.

Cyclospora, which causes diarrhea, is another example. Until last year, foodborne outbreaks in the U.S. were solely linked to produce imported from Central and South America. But in 2018, a salad mix from California caused more than 500 cases in people who ate romaine at fast-food restaurants in 15 states and New York City. Not only was Cyclospora found in unopened bags of the salad mix, it was also detected for the first time in romaine grown on California farms.

Human infections due to foodborne parasites are preventable. We should all stay vigilant and informed, not just about rat lungworm, but the next emerging threat. And the next. After all, from a parasite’s point of view, it’s all about surviving and thriving, which is what the rat lungworm has done for millennia.  

Summer May Soon Fade Away, But Some Outbreaks Are Hanging Around

There’s always a lot to remember when you are going back to school. And this year, it includes a considerable number of foodborne disease outbreaks that are not yet over, according to the federal Centers for Disease Control and Prevention.

The outbreaks that kept CDC investigators busy all summer involved those Cavi Brand whole fresh papayas, deli meats, ground beef, and bison. From the animal-borne side of the house, there are pig ear dog treats, pet hedgehogs, and all that backyard poultry.

Indeed, the summer is ending with active outbreaks involving the three top food-related pathogens; E. coli, Listeria, and Salmonella. For all those going back to school or college early, or maybe taking a late summer vacation, it’s a lot to remember. Here’s a recap:

E. COLI - A seven-state outbreak of Shiga toxin-producing Escherichia coli O103 and 0121 has infected 21 people. Recalled ground bison is the likely cause.  Northfork Bison Distribution on July 16 recalled ground bison and bison patties. Bison Burgers and Buffalo Burgers were other names for the products. Also included was a 4-ounce burger patty.  Northford is a Canadian company based in Saint-Leonard, Quebec.

No deaths are associated with the outbreak, but eight infected people required hospitalization. The CDC cautions consumers not to eat and restaurants and retailers not to sell or serve any of the recalled ground bison products.

Regulatory officials collected records from the restaurants where ill people ate ground bison. “These records showed that the ground bison produced by NorthFork Bison Distributors, Inc. was sold in several restaurants where ill people ate ground bison,” CDC reports.  No cases of the hemolytic-uremic syndrome, a sometimes fatal kidney disease, are connected to the outbreak. The CDC; the US Food and Drug Association; and the Canadian Food Inspection Agency are continuing the investigation.

LISTERIA - This past spring deli meat and cheese sickened eight people in four states with listeriosis. One death occurred. But, there’s been nothing more since that report on April 17.

Both FDA and USDA’s Food Safety and Inspection Service are “monitoring the outbreak,” according to the CDC. Epidemiologic and laboratory evidence indicated that meat and cheeses sliced at deli counters were responsible for the outbreak.  The outbreak strain was present at multiple deli counters.  The CDC did not advise consumers to avoid eating deli products.   It did warn retailers to clean and sanitize deli slicers. And, people at high risk, especially the elderly and pregnant women, were advised to be careful with deli meat and cheeses.

SALMONELLA -  Pig ears, a treat for dogs, have spread Salmonella illnesses to 127 people in 33 states. The dog treats have not killed anyone, but they’ve sent 26 people to the hospital.

And the outbreak strain is antibiotic-resistant to amoxicillin-clavulanic acid, ampicillin, cefoxitin, ceftriaxone, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfisoxazole, and tetracycline.

The CDC and FDA have warned consumers not to buy or feed any pig ears, including any that are already purchased. This outbreak appears to be ongoing as the number of illnesses increased by 34 during the last two weeks of July.

Pig ear victims also include the very young. More than one in five are younger than five years old. Pig ear dog treats from multiple suppliers are blamed for the outbreak.   “No single supplier, distributor or common brand of pig ear treats have been identified that could account for all the illnesses,” CDC reports.

The initiation of three pig ear recalls during July are associated with the Salmonella outbreak. They include Pet Supplies Plus, Lennox Intl Inc., and Lennox Intl. All three recalled their pig ears for possible contamination with Salmonella.

CAVI BRAND WHOLE, FRESH PAPAYAS - An outbreak of Salmonella Uganda with 71 cases reported in eight states is blamed on imported whole fresh papayas sold under the Cavi brand.  On the day after the Fourth of July, CDC warned consumers, saying no one should sell or serve the Cavi brand papayas. Eating any papayas imported from Mexico was also discouraged.

Importers, suppliers, and other foodservice providers were warned not to sell or serve any Cavi brand papayas, which were distributed by Agroson’s LLC.

Epidemiologic and traceback evidence indicates the Cavi brand whole, fresh papayas imported from Mexico are “a likely source of this outbreak,” according to CDC. Agroson’s LLC did not recall the Cavi brand papayas.   

More than 60 people are confirmed sick with Salmonella infections in a multi-state outbreak linked to fresh papayas from Mexico, according to a public alert issued this afternoon.  Consumers should check their homes for papayas imported from Mexico and dispose of them. Anyone who has fresh papayas of unknown origin should error in the side of caution and also throw away the fruit.

“Throw the papayas away, even if some of them were eaten and no one has gotten sick. Do not eat fruit salads or other mixes that include papayas from Mexico,” the CDC’s alert says. “If you aren’t sure the papaya you bought is from Mexico, you can ask the place of purchase. When in doubt, don’t eat the papaya. Throw it out.”

Anyone who has had papayas from Mexico, including consumers, restaurants and other foodservice operations, should wash and sanitize places where papayas were stored: countertops and refrigerator drawers or shelves. 

Current outbreak details - Salmonella Uganda As of today, a total of 62 people infected with the outbreak strain of Salmonella Uganda have been reported from eight states. Illnesses started on dates ranging from Jan. 14 to June 8. Most illnesses have occurred since April. Ill people range in age from 1 to 86 years old, with a median age of 60. Fifty-three percent of ill people are female. 

BACKYARD POULTRY - By mid-July, there were 768 human Salmonella illnesses in 48 states in deadly outbreaks caused by keeping a backyard flock of chickens. The outbreak blamed on backyard poultry grew by 489 between mid-June and mid-July.

The outbreak involves multiple Salmonella serotypes. Two deaths have occurred, one in Texas and one in Ohio. For 122 or 29 percent of the Salmonella cases, hospitalization was required.   Epidemiologic and laboratory evidence points to contact with backyard poultry, such as chicks and ducklings, from multiple hatcheries are the likely source of the outbreaks. Of 315 interviews with ill people, 237 or 75 percent reported contact with chicks or ducklings.

Others reported visits to agricultural stores or hatcheries. From others, environmental samples came from backyard poultry environments.  “Backyard poultry from multiple hatcheries are the likely source of these outbreaks,” CDC reports. “Regardless of where poultry is purchased, they can carry Salmonella germs that can make people sick.”

Pet hedgehogs are the likely source of the Salmonella Typhimurium that’s sickened 47 people in 21 states. Eight required hospital stays, but no deaths are associated with the outbreak.

The outbreak, which started last year, continued to grow over this summer. It added 20 cases between May and August this year.  In interviews, 26 or 74 percent of 35 ill people interviewed said they’d had close contact with a pet hedgehog. The ages of the unfortunate run from 2 to 95 years of age. The median age is17 years old, and 67 percent are female.

SAN DIEGO COUNTY FAIR OUTBREAK - The June outbreak that took the life of a 2-year old boy and infected nearly a dozen other children with E. coli O157: H7 likely occurred from exposure to the bacteria at the San Diego County Fair.  DETAILS - Toddler dies from E. coli infection after visit to petting zoo at county fair.  A 2-year-old is dead and three other children aged 2 to 13 are sick after visiting a San Diego County Fair petting zoo.  According to the San Diego Health and Human Services Agency (HHSA), the children were infected with a Shiga-toxin causing E. coli  bacteria, or STEC, from contact with farm animals at the fair. HHSA... 

San Diego County’s environmental health inspectors have collected samples from individual animals who were at the fair along with swabs of the surrounding environment. The county sent the samples to the federal Centers for Disease Control and Prevention in Atlanta for testing and analysis.

But county health officials say none of their 32 environmental samples turned up an exact source at the fairgrounds. Petting zoo, pony rides, and cattle areas were all suspected, but no positive results came back.   “Even though we have not found a specific animal that we can say the outbreak came from,” said Dr. Eric McDonald, “we have known that the cases all were people who went to the fair and had animal exposure in the livestock barn area.”

Many animals were removed from the livestock barn before the environmental samples were collected. Competition at the fair requires weekly rotating of the animals kept in the livestock barn.


(CNN)  Its safe to say 183 tons is a lot of crab meat. It's certainly a lot of crabmeat to import from other countries and repackage as US-raised blue crab. 

The vice president of a Virginia seafood company pleaded guilty in federal court this week to taking part in this weighty scam. According to a release from the Department of Justice, Michael P. Casey of Casey's Seafood admitted to conspiring with others within the company to falsely label imported crab meat and re-sell it to grocery stores and retailers. 

All in all, the crabmeat involved in the five-year-long bait-and-switch amounted to a wholesale value of $4.3 million. 

G. Zachary Terwilliger, U.S. Attorney for the Eastern District of Virginia, said the scam violated the Lacey Act, which prohibits the import, export or sale of fish plants or wildlife that have been possessed or acquired in ways that violated state or federal law. It also violated the trust of the local seafood industry. 

"This fraud causes real financial harm to the fragile maritime economies here in the region, and threatens to tarnish the good name of the watermen and women who have worked this estuary for generations," Terwilliger said. 

The Justice Department noted a significant blue crab decline beginning in 2010, which Casey claimed in his plea deal made it harder for Casey Seafood to produce enough blue crab to meet demand. 

"As part of the guilty plea, Casey further admitted that beginning at least as early as 2010, and continuing through June 17, 2015, he was aware that company employees had been directed to unpack foreign crab meat from suppliers' containers, comingle it with domestic blue crab and other types of crab, and re-pack that crab meat into Casey's Seafood containers, all of which were labeled 'Product of USA,'" the release reads. 

Michael P. Casey is the second person at the seafood company to plead guilty to the scam. James R. Casey the founder of Casey's Seafood Inc and Michael P. Casey's father, was sentenced to three years in prison in January for his part in the scam. 

Researchers Find Animals In Salad Discoveries Not As Rare As Believed
Most reports of animals being found in fresh produce involved frogs, according to a University of Illinois study.  More than 50 percent of 40 incidents involved frogs, but lizards, snakes, mice, birds, and a bat, were discovered in salad greens, green beans, or mixed vegetables. Ten of these – nine frogs and one lizard – were alive.

Researchers reviewed online media coverage of wild vertebrates found in prepackaged produce by customers in the United States. They discovered 40 incidents 95 percent occurring during 2008 to 2018, suggesting their frequency may have increased in the last decade.

At least seven incidents involved Pacific Treefrogs and for three it was Green Anoles. At least two frogs were released into non-native areas. Six rodents and three birds were also reported.

Most reports involved amphibians (52.5 percent) and reptiles (22.5 percent), while fewer contained mammals (17.5 percent) and birds (7.5 percent), according to the study published in Science of the Total Environment journal.

“There’s a big food safety concern about any wildlife that gets into fields where fresh produce is grown, leading to various control measures, sometimes even drastic tactics,” said Daniel Hughes, postdoctoral researcher in the Department of Animal Sciences at the University of Illinois and lead author.

Incidents were reported from 20 states and eight had at least two issues. Texas and Florida recorded the most with five each and California and New York had four each.

In April 2017, a dead bat was found in packaged salad from a grocery store in Florida. Fresh Express recalled some cases of Organic Marketside Spring Mix distributed to certain Walmart stores.

The CDC recommended post-exposure rabies treatment for two people. The virus wasn’t detected in remains of the animal found in the bagged salad.  “You’d have to spend minutes checking each plant. Romaine, for example, is lettuce folded on lettuce, where it’s easy for moisture-seeking frogs to hide. From a business perspective, can you really spend minutes to check each leaf?”

NY Officials Investigating Cyclospora Outbreak
For a month now people in New York have been testing positive for parasitic infections that health officials say appear to have a foodborne vector.  There are currently 11 laboratory-confirmed patients infected with the Cyclospora parasite, according to an alert from the New York State Department of Health. At least three specific foodservice providers have been reported by some of the patients. 

“Several of the cases interviewed report they dined at the following establishments: The Italian American Community Center in Albany; A buffet during a private graduation event at Union College in Schenectady; Prime Life Restaurant at Beltrone Senior Living Community Center in Colonie,” according to the state health department.

E. coli from beef to romaine: Can the past be the prelude?
Gary M. Weber, president of G.M. Weber Consulting LLC, submitted this column for original publication in Food Safety News. Numerous E. coli O157:H7 outbreaks linked to Romaine lettuce have been a tragedy for both consumers and the leafy greens industry. The leafy greens industry is aggressively addressing approaches to prevent future outbreaks.... 

Green Giant, Trader Joe’s, other brands of vegetable products recalled for Listeria

By News Desk on Jul 01, 2019 11:07 pm Saying state inspectors found Listeria monocytogenes in a sample of an unspecified fresh vegetable product, Growers Express LLC launched a recall of Green Giant and other brands of products from various retailers in dozens of states. Self-described as “the primary licensed partner of Green Giant Fresh, the exclusive fresh produce arm of the iconic Green…

Sprout, Tofu company warned 18 months after FDA inspectors found bugs, rodents, Listeria in Chicago

By News Desk on Jul 01, 2019 12:04 am The FDA issued a warning letter in recent days regarding an inspection 18 months ago at a sprout and tofu facility where federal officials found live rodents and cockroaches, as well as Listeria bacteria.  In the letter, regional officials with the Food and Drug Administration told Steven Seeto that his company Fortune Food Product Inc.... 

Study finds pathogen issues with ready-to-eat salad and sprouts

By News Desk on Jun 19, 2019 12:01 am A study by German researchers has raised concerns on the microbiological quality of ready-to-eat salad mixes and fresh sprouts. The three-year research project by the Max Rubner Institute also found the microbiological quality of cucumbers, carrots and mushrooms was good.  Mixed lettuce received a good to medium result and herbs were rated as medium. The… 

Diapers And Salmonella

County public health officials in Omaha, NE, have confirmed they are investigating a Salmonella outbreak at a daycare center, but they have not reported how many of the 100 children enrolled at the center are sick.

Health department spokesman Phil Rooney said it could be something as simple as employees not properly washing their hands after changing a child’s diaper and then handling or serving food.

The implicated Elite Childcare Academy location has closed until further notice for cleaning and employee training. The daycare center cannot reopen without permission from public health officials. 

The business operators sent a notice to parents and guardians of children enrolled at the daycare center asking that they complete a survey to help determine the source of the Salmonella.

Last Summer’s Outbreaks Turn Attention TO CYCLOSPORIASIS

It’s uncomfortable to talk about intestinal illness known as cyclosporiasis for many to think about because it’s caused by the microscopic parasite Cyclospora cayetanensis. And as recently as the late 1990s, Americans did not have to worry about it unless they traveled abroad. The world, however, changed in 1996 when Guatemalan-grown imported raspberries gave the Clyclospora parasites the ride they needed to cause a first of its kind cyclosporiasis outbreak across both the United States and Canada.

That first North American cyclosporiasis outbreak in 1996 “was an early warning to public health officials and produce industry that the international sourcing of produce means that infectious agents once thought of as only causing traveler’s diarrhea could now infect at home.”

The federal Centers for Disease Control and Prevention did confirm 2,810 cyclosporiasis patients. That means there were likely thousands of additional people infected, but they were not verified.