Category Archives: Microbiology

Research – Lowest number of recorded Hepatitis A cases, five other food and waterborne diseases rising towards pre-pandemic levels

ECDC

Hepatitis A cases in 2021 were at their lowest levels since EU-level hepatitis A surveillance began in 2007, while five other food and waterborne diseases are rising towards pre-pandemic levels. The information is revealed in the Annual Epidemiological Report 2021, of which six chapters are published today by ECDC.

The chapters cover diseases causing  the highest number of  food- and waterborne infections in the EU/EEA, namely campylobacteriosis, salmonellosis, yersiniosis, shigatoxigenic Escherichia coli infection, listeriosis, and hepatitis A.  

In the EU/EEA, the hepatitis A notification rate was exceptionally low in 2021, with 0.92 cases per 100 000 population, compared to 2.2 in 2019. This can be attributed primarily to the COVID-19 pandemic and restrictions, including reduced international travel.  

However, a sharp decline in the trend of hepatitis A cases has also been evident in the EU/EEA over the last five years. Additional factors contributing to this may be the heightened awareness of hepatitis A transmission, increased preventive measures such as practising good hygiene and increased vaccine uptake among at-risk groups. Increased natural immunity in at-risk groups following a large multi-country outbreak occurring in 2017 and 2018 may also be of importance.  

In 2020, the number of cases of campylobacteriosis and salmonellosis, the two most commonly reported gastrointestinal infections in the EU/EEA, decreased notably due to the COVID-19 pandemic. Unlike hepatitis A, these appeared to increase in 2021, but the levels are still well below those of the pre-pandemic years. This could partly be an effect of reduced travel as travel-related infections were at their lowest in 2021. 

Listeriosis, shigatoxigenic Escherichia coli infections and yersiniosis trends decreased less notably in 2020 and the number of cases returned to the pre-pandemic levels in 2021. This might be due to the more severe symptoms caused particularly by listeriosis and shigatoxigenic Escherichia coli infections, which are then more likely to be diagnosed and reported. Additionally, many of the cases are acquired  within the EU/EEA, and the numbers are not as affected by international travel restrictions.  

In 2021, although the COVID-19 pandemic was still ongoing, the gradual reduction of COVID-19 restriction measures, along with the return to normal daily life (social events, doctor’s visits, travel), the reopening of bars, restaurants and catering facilities (i.e. schools, workplaces), may explain the increase in cases of the five food- and waterborne diseases.   

Research – Campylobacteriosis – Annual Epidemiological Report for 2021

ECDC

The notification of campylobacteriosis is mandatory in 22 EU Member States, Iceland, Liechtenstein, and Norway. In five EU Member States (Belgium, France, Greece, Italy, and the Netherlands) notification is voluntary. The surveillance systems for campylobacteriosis have full national coverage in all EU Member States except four (France, Italy, the Netherlands, and Spain). The coverage of the surveillance system in 2021 is estimated to be 20% in France and 64% in the Netherlands. These proportions were used when calculating notification rates for these two EU Member States. No estimate of population coverage in Italy and Spain was provided, so notification rates were not calculated for these two countries. The drop in cases in Luxembourg in 2019 is a surveillance artefact caused by a change to non-culture-based methods (PCR) in private laboratories, resulting in a reduced number of isolates sent to the national reference laboratory. From 2020, laboratory confirmation with PCR is included in the notification system which, along with a new electronic laboratory notification system, is expected to result in an increase in Campylobacter notifications. Greece has reported data on laboratory-confirmed cases collected from public hospitals from 2018 onwards. For 2020 and 2021, Spain has not yet received data from all regions normally reporting and the case numbers are therefore lower than expected. All countries reported case-based data except Belgium, Bulgaria, and Greece, which report aggregated data. Both reporting formats were included to calculate numbers of cases, notification rates, disease trends, and age and gender distributions.

Click to access campylobacteriosis-annual-epidemiological-report-2021.pdf

Research – A Comprehensive Review of Variability in The Thermal Resistance (D-Values) of Food-Borne Pathogens—A Challenge for Thermal Validation Trials

MDPI

Abstract

The thermal processing of food relies heavily on determining the right time and temperature regime required to inactivate bacterial contaminants to an acceptable limit. To design a thermal processing regime with an accurate time and temperature combination, the D-values of targeted microorganisms are either referred to or estimated. The D-value is the time required at a given temperature to reduce the bacterial population by 90%. The D-value can vary depending on various factors such as the food matrix, the bacterial strain, and the conditions it has previously been exposed to; the intrinsic properties of the food (moisture, water activity, fat content, and pH); the method used to expose the microorganism to the thermal treatment either at the laboratory or commercial scale; the approach used to estimate the number of survivors; and the statistical model used for the analysis of the data. This review focused on Bacillus cereus, Cronobacter sakazakii, Escherichia coli, Listeria monocytogenes, and Clostridium perfringens owing to their pathogenicity and the availability of publications on their thermal resistance. The literature indicates a significant variation in D-values reported for the same strain, and it is concluded that when designing thermal processing regimes, the impact of multiple factors on the D-values of a specific microorganism needs to be considered. Further, owing to the complexity of the interactions involved, the effectiveness of regimes derived laboratory data must be confirmed within industrial food processing settings.
 

 

Research – Prevent Illness From C. perfringens

CDC

CDC Clost perf

Clostridium perfringens bacteria are one of the most common causes of food poisoning. CDC estimates that the bacterium causes nearly 1 million foodborne illnesses in the United States every year.

C. perfringens makes spores, which are inactive forms of the bacterium that help it survive heat, dryness, and other environmental conditions. Under certain conditions, such as when food is kept at an unsafe temperature (between 40°F and 140°F), C. perfringens spores can transform into active bacteria, which multiply in the food. After someone eats food containing C. perfringens, it can produce a toxin (poison) that causes diarrhea.

Foods cooked in large batches and held at unsafe temperatures are typically involved in outbreaks of C. perfringens food poisoning. Specific foods commonly linked to C. perfringens food poisoning include

  • Poultry, such as turkey and chicken
  • Meat, such as beef and pork
  • Gravy

Outbreaks of C. perfringens food poisoning tend to happen in settings where large groups of people are served and keeping food at proper temperatures may be difficult—for example, hospitals, school cafeterias, prisons, nursing homes, and large events with catered food.

Most of these outbreaks happen in November and December. Many of them have been linked to popular holiday foods, such as turkey and roast beef.

New Zealand – Don’t contaminate your plate this summer – be a Chicken Scene Investigator – Campylobacter

MPI

It would be a crime for your whānau and friends to come down with foodborne illness this festive season – so New Zealand Food Safety and the Chicken Scene Investigators have got your back.

“Each year, over our summer, there is a rise in cases of foodborne illness and hospitalisations,” says New Zealand Food Safety deputy director-general Vincent Arbuckle.

“The most commonly reported illness is campylobacteriosis – caused by Campylobacter bacteria – with our youngest and oldest having the highest rates of infection.

“There were 5,729 confirmed cases of campylobacteriosis in 2021, with 846 people needing hospital treatment, up from 718 in 2020. And 2022 looks set to follow a similar trajectory, with more than 5,300 cases nationally so far.

“The most common source of Campylobacter from food is raw or undercooked chicken.

“So, one big thing you can do this festive season to keep your whānau and friends healthy is to make sure you handle raw chicken safely. Cook it properly and use separate utensils and chopping boards, and, as with all food, don’t leave it out in the heat of the day, both before cooking and after you’ve finished eating.”

To help you with this, New Zealand Food Safety today launches a new food safety campaign. In a series of videos, our 2 Chicken Scene Investigators invite you to join them to spot the chicken-handling crime.

“Campylobacteriosis symptoms are nasty. They include diarrhoea, fever, headache, muscle aches, abdominal pain, and vomiting. It may also develop into more severe illness such as Guillain-Barré Syndrome, a disorder in which the body’s immune system attacks its nerves, sometimes resulting in permanent paralysis,” says Mr Arbuckle.

If you have symptoms, you can call Healthline for free anytime on 0800 61 11 16, or contact your doctor or practice nurse for advice.

“So, wherever you’re gathering – from BBQs to work do, beach parties to kai at the marae, Christmas lunch or potluck dinner – make sure you don’t contaminate your plate this summer.”

Te Whatu Ora medical officer of health Jay Harrower adds: “Every year thousands of people are diagnosed as being infected with Campylobacter, and for some it can be very serious. Across New Zealand Campylobacter cases are spiking once again this summer, but there are simple steps everyone can take to reduce the risk to them and their whānau.”

Chicken Scene Investigator tips to keep your whānau and friends safe:

  • Keep your raw chicken separate from ready-to-eat and fresh foods, using separate chopping boards, plates, and utensils. Alternatively, wash them properly with hot soapy water before using for other foods.
  • Don’t wash the chicken. Rinsing it will just spread the bacteria to other surfaces. Pat it dry with a paper towel instead, if needed.
  • Wash your hands in warm soapy water after handling raw chicken.
  • Make sure the chicken is fully cooked before serving – it can’t be pink and the juices should run clear. Or use a meat thermometer, if you have one, to ensure the chicken is steaming hot (over 75°C) all the way through.
  • Use a different plate for raw and cooked chicken.
  • If in doubt, clean surfaces and utensils some more, cook your chicken some more.

Safe barbecuing of food

Campylobacter infection: symptoms and advice

Watch the Chicken Scene Investigators on YouTube

The tea towel (15 seconds) 

The knife (15 seconds) 

Image

Food Safety at Christmas

Norway -Cucumber from Spain is a suspected source of infection in outbreaks of Salmonella

Matportalen

After an extensive outbreak investigation, cucumber from a Spanish supplier stands out as the likely source of infection in a salmonella outbreak that started in November. No new cases of illness have been reported in recent weeks, which may indicate that there are no longer any contaminated products on the market and that the outbreak is probably over.

There are now 72 people registered who have become ill from the gastrointestinal bacterium Salmonella Agona. The peak of infection in Norway was in mid-November, and the last reported case of the disease came on 2 December. Cases of the same outbreak strain have also been reported in Sweden and the Netherlands, in the same period.

– It is not always possible to find the source of infection in such outbreaks, but now some batches of cucumber from a Spanish supplier have been identified as the most likely, says Catherine Svindland, senior adviser at the Norwegian Food Safety Authority.

These batches of cucumber are no longer on the market. The Norwegian importers of cucumbers from the supplier have intensified the sampling of cucumbers as an additional safety measure. Salmonella was not found in these samples. The Norwegian Food Safety Authority has notified the Spanish authorities and other countries in the EU about the suspicion.

The contaminating cucumbers have probably not been on the market since November.

The outbreak investigation continues to, if possible, definitively establish that these cucumbers are the source of infection. This can be challenging, as the polluting products are likely to be out of the market and people’s fridges.

France – Nestlé allowed to restart pizza plant linked to deadly E. coli outbreak

Food Safety News

Nestlé has been given permission to partially reopen a plant in France where pizzas behind a serious E. coli outbreak were made.

French officials from the Nord area of the country in the Hauts-de-France region gave the green light this past week for operations to restart at the Buitoni factory in Caudry.

Approval only applies to production of pizzas with cooked dough. The line making pizzas with no re-baking of dough, such as the Fraîch’Up range, will not restart yet.

Fraîch’Up frozen pizzas were the source of the largest E. coli-HUS outbreak ever documented in France. 

One element of the plan to restart has included the dismantling and cleaning of 19,000 parts on the production line.

England – Differential impact of the COVID-19 pandemic on laboratory reporting of Norovirus and Campylobacter in England: A modelling approach

PLOS One

CDC Campy

The COVID-19 pandemic has impacted surveillance activities for multiple pathogens. Since March 2020, there was a decline in the number of reports of norovirus and Campylobacter recorded by England’s national laboratory surveillance system. The aim is to estimate and compare the impact of the COVID-19 pandemic on norovirus and Campylobacter surveillance data in England.

Denmark – Outbreak of invasive Listeria infection sequence type 7 in Denmark caused by fish meatballs

SSI

Between mid-August and December 2022, the Statens Serum Institut has registered 11 cases of Listeria monocytogenes . The Statens Serum Institut, the Danish Food Agency and the Danish Food Institute DTU have investigated the disease outbreak and identified fish cakes as the source.

About the disease outbreak

Between mid-August and December 2022, the Statens Serum Institut registered 11 people who are infected with the same type of Listeria monocytogenes (figure 1). Among the sick are 4 men and 7 women. In relation to age, there is one child and 10 adults (median age is 77). The patients are infected throughout the country (table 1). Interviews with six patients showed that all had eaten fish cakes.

Number of cases of Listeria monocytogenes sequence type 7 in Denmark per week, 2022 (n=11)

Table 1. Patients with the same type of Listeria monocytogenes in Denmark, August to December 2022, per region (n=11)

Region

Number of patients

The capital  4
Central Jutland 2
Northern Jutland 0
Zealand 2
Southern Denmark 3
Total 11

The investigation of the outbreak

The outbreak is handled by the Central Outbreak Group, which consists of SSI, the Danish Veterinary and Food Administration and the DTU Food Institute. SSI stands for whole-genome sequencing of listeria isolates from the patients and interviews with patients or relatives with a view to identifying a possible source of infection. The outbreak investigation showed that fish meatballs were the cause of the disease outbreak. The fish meatballs were recalled from stores on November 8, 2022.

The outbreak strain

The bacteria is of the type Listeria monocytogenes . By whole-genome sequencing of the Listeria monocytogenes bacteria isolated from the patients, it can be seen that they are very closely related and belong to sequence type 7.