13 sick pulling mussels from the shell

I love my shellfish – mussels and scallops (oysters are sorta gross) – but the kid was diagnosed with a shellfish allergy so they’re an occasional lunch while she’s at school.

Health types in the UK report on six cases of diarrhetic shellfish poisoning (DSP) following consumption of mussels in the United Kingdom (UK). The mussels contained high levels of heat-stable okadaic acid (OA)-group toxins. Here we describe the environmental and epidemiological investigation carried out in response to the outbreak.

In June 2019 (day 0), Public Health England South West was notified by the local authority of three diners who were unwell following consumption of mussels in a restaurant 5 days earlier. The local authority had determined that the restaurant had had received a batch recall notice, also 5 days earlier, from the shellfish producer for the mussels because of elevated toxin levels but this was not seen before the mussels were served that day. On day 1, PHE South West received a report from the county neighbouring the first of gastrointestinal illness linked to mussels from the same producer. A multi-agency outbreak control team was therefore convened on day 2 and led by the PHE South West health protection team.

An alert was sent to all health protection teams across England on day 2 asking about any reported cases of gastrointestinal illness following consumption of mussels. Local authorities in areas of product distribution were informed of the identified risk by email. Persons reporting illness who were identified by local authorities as having consumed the affected mussels were asked by PHE to complete a bespoke questionnaire on exposure and clinical data.

A probable case of DSP was defined as an individual with diarrhoea, three or more loose stools in 24 h, or vomiting or abdominal cramps or nausea, with date of onset from 7 days before to 1 day after notification of the outbreak, and time of onset 30 min to 24 h following consumption of mussels harvested from the affected site. Confirmed cases were as probable, but with an absence of pathogens in a stool sample that would otherwise explain illness.

Thirteen individuals reported to have been unwell after consumption of mussels were contacted. Completed questionnaires were received from seven individuals, of which three were confirmed, and three probable cases. The cases ate at four separate venues. One respondent did not meet the case definition as symptom onset was more than 24 h following consumption.

The mean age of cases was 59 years (range: 37–76 years); three were male and three were female. All cases reported eating steamed mussels. Five cases ate mussels as a main course and one as a starter. Reported portion sizes ranged from 11 to 50 mussels.

The mussels were produced in an offshore marine area. A routine shellfish monitoring programme is in place throughout England and Wales, including at the affected site. As a part of this programme, the water column is sampled every 2 weeks from April to September and cell counts of potentially harmful algal species are measured. Shellfish flesh samples are also tested for the presence of selected European Union (EU)-regulated biotoxins every 4 weeks during April to September each year unless phytoplankton counts and/or shellfish toxins are quantified above specified warning limits that require further precautions, including re-testing and closure.

Lipophilic toxin determination, including that for OA-group toxins, is routinely carried out using the method specified in in the EU-Harmonised Standard Operating Procedure for determination of lipophilic marine biotoxins in molluscs by LC-MS/MS [1]. Additional flesh and water samples were taken in advance of the planned sampling date following a report to the local authority from a local fisherman of a red-coloured algal bloom six miles offshore from the production site.

The local authority determined the source of the mussels by questioning venues linked to reports of illness. Subsequently, the shellfish producer provided the outbreak control team with a complete list of all businesses who had received the affected mussels. Mussels from the site were harvested daily from 9 to 5 days before notification of the outbreak for commercial sale. The mussels were not tested by the producer for the presence of toxins. A large volume of mussels was distributed to seafood wholesalers, restaurants and pubs, and subject to the recall notice distributed by the producer 5 days before reports of illness to PHE. A limited number of businesses not linked to any known cases, including wholesalers, retailers, restaurants and pubs, responded to the recall stating they had sold some of the affected produce. No produce was found to still be in circulation at the time of the outbreak response.

Water column and shellfish flesh sampling results are summarised in Table 2. Measured densities of Dinophysis spp. in the water column increased rapidly from being undetectable 16 days before outbreak notification to 1,600 cells per litre 7 days before, coinciding with the time of harvesting of the affected batch and exceeding the England, Wales and Northern Ireland Food Standards Agency trigger level of 100 cells per litre. The level of total OA-group lipophilic toxins in mussel flesh was 338 µg OA equivalents (eq) per kg, following application of measurement uncertainty, 7 days before outbreak notification. This exceeded the maximum permitted limit (MPL) of 160 µg OA eq per kg defined by European Commission (EC) regulation 853/2004 [2]. Toxin concentrations quantified showed that an average of 94% of the OA-group toxins present in the mussels consisted of OA itself, with the remainder being dinophysistoxin 2 (DTX2).

Water column sampling 7 days before outbreak notification did not detect other harmful algal species apart from Pseudo-nitzschia spp., the causative diatom for domoic acid responsible for amnesic shellfish poisoning, at 1,320 cells per litre. This is below the trigger level of 150,000 cells per litre for this species.

Routine shellfish sampling at the same site during the same time period did not detect paralytic shellfish poisoning toxins. Trace levels of yessotoxins were detected, but along with traces of azaspiracids, they were well below regulatory levels. Amnesic shellfish poisoning toxins were below the limit of quantitation (LOQ).

In response to the elevated toxin levels quantified and reported 5 days before outbreak notification, the shellfish bed was immediately closed for harvesting as per standard practice in England. The Food Standards Agency urgently contacted local authorities of places where the affected product had been distributed to ensure that wholesalers and venues had acted upon the recall. Venues were asked whether any product had been frozen, for example in the form of stock, as this would not deactivate the toxin, but there was no evidence this had been done.

Discussion

We report on six cases of DSP associated with consumption of mussels harvested in the South West of England. Without an available validated test for relevant toxins in human samples, the diagnosis was made based on characteristic clinical symptoms, including diarrhoea, abdominal pain, nausea and fever/chills, elevated levels of OA-group toxins in the flesh of mussels from the same batch as those consumed, the absence of faecal pathogens in stool of cases and epidemiological evidence of exposure to the produce.

DSP occurs following consumption of seafood containing high levels of the heat-stable OA-group toxins produced by dinoflagellates including Dinophysis spp., and is characterised by a rapid-onset of self-limiting gastrointestinal illness [3,4]. Recognised outbreaks of DSP are rare. Seventy cases were identified in 2013 following consumption of mussels harvested around the Shetland Islands [5] and 49 cases were identified in 1998 following consumption of UK-harvested mussels in London [6]. Outbreaks have been recorded in recent years in China, the United States, France and Canada [4,79].

The lowest-observed-adverse-effect level of OA is 45 to 50 µg OA eq per person [4,10]. In our study, an average main course portion of mussels (500 g in shell) would provide 41 µg OA eq., using a flesh weight yield of 24% [11]. This level of exposure is consistent with DSP as the cause of illness considering variability in portion sizes, flesh yield, body weight and toxin levels at the production site. Individual mussel sizes served were unavailable but would likely vary. Therefore, overall estimated portion weight was used to calculate the exposure dose. A limitation is that body weight (bw) was not recorded for cases and because of this, OA eq per kg bw could not be calculated.

A shellfish biotoxin programme monitoring the occurrence of harmful algal blooms and toxins in classified shellfish production areas in the UK, alongside food business operator checks, remains a robust system to protect population health. Nonetheless, a rapid increase in concentrations of Dinophysis spp. cells within the waters of the production site may have contributed to the outbreak, in tandem with shellfish harvesting occurring before official control results were reported and site closure. Whyte et al. (2014) demonstrated that a similar rapid increase in Dinophysis levels, resulting from a change in prevailing wind direction, occurred in the 2013 Shetland Islands origin outbreak [5]. Transdisciplinary research is required to predict future risk and inform monitoring, particularly given likely changes in the distribution of potentially-toxic species particularly if temperature of ocean water increases [12]. Our investigation suggested that affected produce may have been sold by restaurants and pubs with no known linked cases. Given that DSP is a self-limiting illness that may be under-reported by cases and has low awareness among clinicians, the actual number of persons affected in this outbreak is likely to be higher [13].

This outbreak highlights that clinicians and public health professionals should be aware of algal-derived toxins as a potential cause of illness following seafood consumption, and that the need for effective end-product testing of shellfish to ensure food safety remains.

Outbreak of diarrhetic shellfish poisoning associated with consumption of mussels, United Kingdom, May to June 2019

28.aug.19

EuroSurveillance

Nick Young, Charlotte Robin, Et al

https://eurosurveillance.org/content/10.2807/1560-7917.ES.2019.24.35.1900513

NZ mussels at centre of food poisoning outbreak

Seafood lovers have been warned to be careful with raw mussels after an outbreak of food poisoning.

New Zealand Food Safety announced on Friday it’s seen an uptick in the number of people contracting food poisoning from Vibrio parahaemolyticus.

Most of the people who got sick ate commercial grown mussels harvested in Coromandel.

“It is possible that the strain of vibrio parahaemolyticus is unusually aggressive, which may mean that even low numbers could cause illness,” NZ food safety director of regulation Paul Dansted said.

“Additional testing of mussels and the waters that they are being grown in is also underway to help us understand why this has happened.

“The mussels at the centre of the outbreak were all bought in their raw state, in the shell. They are not the mussels that can be bought in plastic pottles. Those mussels are cooked and marinated and are not affected.”

NZ Food Safety says people need to be careful when cooking mussels and heat them above 65C. It’s also advised to wash hands after handling shellfish, and avoid cross-contamination between raw and cooked shellfish.

39 sick with Norovirus from frozen mussels in Spain

The appropriately named Olive Press has reported 39 people have become infected by norovirus after eating contaminated frozen mussels.

The outbreak  occured in Valencia, but the infected batch had already been distributed to Andalucia, the Balearic Islands and nine other regions.

The Spanish Agency for Consumer Affairs, Food Safety and Nutrition has issued a warning to anyone who has bought frozen mussels from the batch to throw them away immediately.

The product is frozen cooked mussels from Galicia, called Mejillón media concha súper, under the Estrella Polar brand.

Any packaging containing the lot number 010DOP-18 should be thrown out.

The European Competent Authorities have also been informed through the Rapid Alert System for Food (RASFF).

Bringing mussels to a hospital patient isn’t a good idea

A couple of weeks ago I had a what I thought was the start of a noro nightmare: one of the 9 year-old hockey players I coach told me his stomach wasn’t feeling great. He asked to sit a shift. As I went over to check on him a couple of minutes later, he tilted his head forward and yacked through his mask on the bench. I was in the splash area, forget within the aerosolization zone.

I was lucky. No puking for me.

Norovirus is often linked to events like this, an ill food handler, or a couple of food types: shellfish or berries.

According to the Dunbarton and Vale of Leven Reporter, a couple of these sources got mixed as someone brought mussles into a hospital for a patient and the bivalves led to a bunch of other illnesses.

An outbreak of the winter vomiting bug which forced hospital bosses to ban visitors from wards was caused by someone bringing mussels in for a patient, it has emerged.

Officials have traced its spread to a visitor bringing in mussels for an inpatient at Wansbeck General Hospital in Ashington, Northumberland.

It is thought to have affected at least 180 people.

The trust said it was working hard to allow visitors in to see patients over Christmas.

Bringing in food that can cause illness in a loved one is kinda dumb. That loved one causing 180 people to get sick, is even worse.

Who steals mussels? People in NZ

MPI Fisheries-Northland reports on facebook that yesterday a member of the public reported a group taking too many mussels from the Whangarei Heads area.

mussel.theftFishery Officers responded to the call and met the men as they came ashore with their vessel. The group had a total of 2,683 mussels between three of them.

The trio were directed to our Whangarei office for the purpose of a formal interview, however the men had other ideas. They decided to take a detour and not go to the office as directed, they will now face not only serious Fisheries Act charges for the shellfish but also for obstructing Fishery Officers.

Blatant offending of this nature will not be tolerated, the men could face charges of up to $250,000 as well as forfeiture of their vehicle, vessel and trailer (all of which was confiscated at the time).

Reminder: the daily limit for green lipped mussels in the Northland area is 50 per gatherer.

And I’ve gone with this version of the video because the lyrics are so beautiful.

 

Recall of fresh mussels in Ireland: due to presence of DSP (diarrhetic shellfish poisoning)

The Food Safety Authority of Ireland (FSAI) is advising consumers of a food recall of fresh mussels supplied from Wednesday of this week to some retail stores throughout Ireland.  The mussels were harvested from Roaringwater Bay, Co. Cork on Monday and Tuesday of this week and may contain harmful levels of diarrhetic shellfish poisoning (DSP) toxins.  These mussels were sold loose and in bags at fresh fish counters in some retail outlets nationwide.  The FSAI is warning consumers who may have the product at home not to eat the affected mussels. The implicated mussels have now been removed from sale.

Symptoms of diarrhetic shellfish poisoning are diarrhea, nausea, vomiting and abdominal pain which can start between 30 minutes to a few hours after ingestion. Complete recovery occurs within a number of days.

The FSAI is warning consumers who may have the mussels to check with the store where they purchased them and not to eat them if they are implicated in this recall.

Food safety inspectors shut down Netherlands mussel trader

Food safety inspectors have stopped a shellfish trader in Zeeland from exporting 47 tonnes of mussels after it failed to take action over two food poisoning incidents in England and Switzerland.

A small quantity of the mussels, which were exported to Ireland, are also being recalled, mussels-500the food safety body NVWA says.

In November, the same company was at the centre of another recall after several people became ill in England after eating mussels containing biotoxins, a poison common in shellfish. Those mussels came from Ireland but had been sold by the Dutch company.

The company was aware of the problem but did not register it with the authorities in time, food safety inspectors say. In December there was a second incident involving mussels in Switzerland. 
Those mussels, said at the time to be of Danish origin, turned out to be from the same Irish consignment as in the English food poisoning case.

Food inspectors have now effectively closed down the trader pending a full investigation and possible criminal charges.

Spring Bay Seafoods Mussels recalled for biotoxin contamination

Damn, these are the only decent mussels I can get in Australia, farmed in Tasmania.

Spring Bay Seafoods Pty Ltd has recalled four blue mussels products from Coles and other retail outlets in VIC, QLD, NSW, TAS, SA, ACT due to naturally occurring marine biotoxin Paralytic Shellfish Toxin (PST). Food products contaminated with Paralytic Shellfish Toxin (PST) may cause illness if consumed. Children and people with weakened immune systems may be more susceptible.

Dozens sick from possibly contaminated mussels

In another case of government-types burying the lede, the Canadian Food Inspection Agency on Sunday warned consumers not to eat certain B.C. mussels.

Half-way through the press release, CFIA stated, “There have been reported illnesses associated with the consumption of these mussels.”

Yesterday, News1130 reported the number of people sick from a bad batch of mussels from Salt Spring Island is now up to 50.

Doctor Eleni Galanis with the BC Centre for Disease Control says they may be contaminated with Diarrhetic Shellfish Poisoning biotoxin or DSP.

"Unfortunately, it’s not a toxin that can be denatured or killed by cooking so even though the mussels have been well cooked, people can still become ill."

The affected mussels were harvested by Island Sea Farms Inc. from the harvest location “Area: BC 13, Sub Area: 15”or “BC 13-15” between July 19 and August 2, 2011.

The following mussels are affected by this alert:

Saltspring Island Mussels
Aquacultured Edulis Mussels
5 lbs (2.27 kg)
All lots up to and including Lot # 289; all harvest dates up to and including August 2, 2011 (2011AU02)
Albion Fisheries Ltd
Mussel N/Shell Saltspring Isl
5 lbs
All harvest dates up to and including August 4, 2011 (8/04/2011)
Pacific Rim Shellfish Corp.
Mussels or Gallo Mussels
Various weights
All harvest dates up to and including July 31, 2011
Albion
SSI Mussels
Various weights
Ship dates of July 20 to August 4, 2011 inclusive
B & C Food
Mussels
Various weights
Processing dates of July 20 to August 4, 2011 inclusive

Retailers and restaurants are advised to check the tags or labels on mussel packages or with their supplier to determine if they have the affected product.
 

Seafood in Kansas sucks, but why is seafood being imported into Hawaii?

I will never buy mussels in Kansas again.

I know, why would anyone buy seafood in the geographic center of the U.S., where the mussels are flown in from Canada, but they’re delicious.

Except the stench from the ones I bought Tuesday still has not left the house. Nasty, nasty stuff.

But why are people in Hawaii importing seafood? Kansas, sure, but Hawaii?

The Hawaii state Department of Health said today it has confirmed 10 cases of salmonella infection on Oahu related to eating previously frozen internationally imported raw ahi.

The people who became ill with Salmonella Paratyphi B reported eating raw ahi, often prepared as poke, that was purchased or served at various locations on Oahu.

The DOH said that as of April 12 there were 13 other confirmed cases of Salmonella Paratyphi B in five other states — California (7), Maryland (2), Pennsylvania (2), Massachusetts (1) and New York (1). The DOH said it is working with the national Centers for Disease Control and Prevention to determine if these cases also involved raw ahi.

The DOH said it also has asked the U.S. Food and Drug Administration to open an investigation of international sources of frozen raw ahi.