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Food safety risk during the pandemic
Food Science and Technology ( IF 2.602 ) Pub Date : 2020-05-28 , DOI: 10.1002/fsat.3402_4.x


The COVID‐19 pandemic is one of the largest public health crises in recent history. Sterling Crew reviews the potential food safety challenges presented by SARS‐CoV‐2 and its impact on the food sector's management and control measures .

The COVID ‐19 pandemic and SARS‐CoV ‐2

COVID‐19 is the name of the disease caused by the novel coronavirus SARS‐CoV‐2. COVID‐19 has changed all of our lives so fundamentally in so many ways. As well as the critical health concerns, it has brought into sharp focus the importance of food and, in particular the availability of safe, healthy and nutritious food through our very complex global supply network.

At the end of December 2019 the severe acute respiratory syndrome COVID‐19 expanded globally from its origins in Wuhan, China. In March 2020 the World Health Organisation (WHO) declared a global pandemic.

This novel coronavirus is a new strain that had not been previously identified in humans and there is therefore still a level of uncertainty. While the virus originally passed from an animal to a human in China, the current cases are a result of human to human transmission. The principle mode of transmission is via respiratory droplets released when people sneeze, cough or exhale. This is why social distancing and the need to stay at least two metres away from others are important. The virus can be spread indirectly when droplets land on objects and surfaces around the infected person, such as tables, doorknobs and handrails. People can become infected by touching these objects or surfaces, then touching their eyes, nose or mouth. That is why it is important to wash your hands at critical moments.

Coronaviruses are a large family which may cause illness in animals and humans. SARS‐CoV‐2 is a strain of a group of severe acute respiratory syndrome‐related coronavirus (SARSr‐CoV). SARS‐CoV‐2 is an enveloped, positive‐sense, single stranded RNA virus. It is a large pleomorphic spherical particle that forms the eponymous corona.

It is believed to have zoonotic origins and has close genetic similarity to bat coronaviruses, suggesting it emerged from a bat borne virus. In humans, several coronaviruses are known to cause respiratory infections ranging from the common cold to more severe diseases, such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS), which caused the 2002 outbreak.

COVID ‐19 transmission by food and its packaging

In such uncertain and challenging times it is important that we use trusted sources and are guided by scientific principles and medical advice. The opinion held by a series of trusted sources (including WHO[1] , The European Food Safety Authority, The Food and Drugs Administration, The Center for Communicable Disease, Public Health England, the Food Standards Agency and Food Standards Scotland) is that COVID‐19 is a respiratory illness. It is not known to be transmitted by exposure to food or food packaging.

The FSA comments in its ‘Qualitative risk assessment on the risk of food or food contact materials as a transmission route for SARS‐CoV‐2’[2] , ‘We consider that the probability that UK consumers will receive potentially infectious exposures of SARS‐CoV‐2 via consumption of food or handling food contact materials or packaging is very low ’. However it acknowledges that the uncertainty factor is high.

This resonates with EFSA's position: ‘It is very unlikely that people can catch COVID‐19 from food. COVID‐19 is a respiratory illness and not known to be transmitted by exposure to food or food packaging. There is no evidence that food is a likely source or transmission route of COVID‐19 ’. However, EFSA is closely monitoring the scientific literature for new and relevant information. EFSA's chief scientist commented ‘Experiences from previous outbreaks of related coronaviruses, such as severe acute respiratory syndrome coronavirus (SARS‐CoV) and Middle East respiratory syndrome coronavirus (MERS‐CoV), show that transmission through food consumption did not occur. At the moment, there is no evidence to suggest that coronavirus is any different in this respect .’

The third party auditing process, which helps drive continuous improvement, food safety and quality and gives a degree of assurance to customers, has had to be put on hold.

The UK Government advises that food business operators should continue to follow the FSA guidance on good hygiene practices in food preparation and their Hazard Analysis and Critical Point (HACCP) processes.

It is particularly important to maintain good hygiene practices around open food (e.g. unpackaged bread, cakes, fruit, salad bars etc.) as this will reduce the risk of contamination of the food. As with food packaging, efforts should be made to ensure it is handled in line with usual food safety practices.

Potential indirect food safety impact

The global food sector is being dramatically impacted both economically and socially, across the entire food network in relation to:

• human resources, such as changes in key personnel;

• supply chains of ingredients, packaging, finished products and equipment;

• sourcing, transportation of people, materials and goods.

The restrictions which many countries have put in place to manage the spread of COVID‐19 have also in turn severely impacted the food sector. The sector may need to rely on alternative suppliers at short notice. Certain ingredients and packaging might be in short supply and food businesses may need to consider leaving out or substituting ingredients in a product. Taking on new staff will require training and ensuring they adopt the business's food safety culture, which is no mean task as some might not have a food background.

The third party auditing process, which helps drive continuous improvement, food safety and quality and gives a degree of assurance to customers, has had to be put on hold. All of the GFSI recognised food safety certification programmes have issued official positions on how they are handling new certifications and re‐certifications in response to the current pandemic and these are posted on their websites. This crisis might well hasten the move towards remote audits, which have already started to take place.

In my opinion all these factors do have the potential to impact negatively on food safety as the current situation is extremely disruptive and is stressing the whole global food supply network, reducing its capabilities and restricting the availability of food.

Food businesses are fortunate to have tried and tested management systems in place. We already have robust management system controls in situ for food safety such as:

• HACCP for mitigation of unintentional/accidental adulteration

• TACCP (Threat Assessment and Critical Control Points) for food defence and the mitigation of intentional ideologically motivated adulteration

• VACCP (Vulnerability Assessment and Critical Control Points) to address food fraud and mitigation of economically motivated intentional adulteration. When the food supply chain is under pressure, unscrupulous people will try to take advantage of shortages and reduced oversight. There is a need to reinvigorate our authenticity approach for economically driven food fraud, which of course can bring with it consequential food safety risks.

The food sector must continue to adhere to good food safety processes and procedures. We are fortunate that food professionals and handlers are already well informed and trained in hand hygiene and cross contamination and already have robust controls in place. A new guidance has been developed by the FSA with the Department for Environment, Food and Rural Affairs (Defra); it covers a range of areas including good hygiene practice, management of employee sickness and social distancing for specific food business settings. It is important that a food business operator identifies and analyses the new food safety and authenticity related risks created by the COVID‐19 crisis and takes action to mitigate them (Figure 1).

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Figure 1
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Food or Food Contact Materials a source or transmission route?

The public perception

We are all consumers of food, which sustains and nourishes us and plays a large part in our culture. The public perception of the risk posed by COVID‐19 will directly impact on people's behaviour. Even though there is no evidence that food is a likely source or transmission route of COVID‐19, some consumers still remain unconvinced.

The public sometimes struggles to understand legitimate scientific qualification around certainty, such as ‘there is no evidence to suggest’ or ‘it's highly unlikely that’. Consumers are looking for certainty in uncertain times, especially from scientists, a trusted profession. However, people's behaviour in dangerous times can be instinctively driven by an innate precautionary principle and some can find the ‘it is not known to be transmitted by exposure to food or food packaging’ position counter intuitive, especially in the context of other advice on avoiding contaminated surfaces and hand washing.

Aerosol and surface stability

A recent report[3] on SARS‐CoV‐2, when compared with SARS‐CoV‐1, looked at the stability of both viruses on various surfaces. The results showed similar stability of SARS‐CoV‐2 on different surfaces to the closely related coronavirus SARS‐CoV‐1. The COVID‐19 causing SARS‐CoV‐2 remained viable in aerosols throughout the three‐hour duration of the experiment, but with a reduced infection rate. The study also showed SARS‐CoV‐2 can survive for up to 72 hours on plastic and stainless steel, 24 hours on cardboard and less than four hours on copper. Both viruses had an exponential decay in virus titer across all the experimental conditions.

The study also looked at SARS‐CoV‐2 under different conditions of temperature and pH. The virus was highly stable at 4°C but was sensitive to heat at 70°C, with inactivation being reduced to five minutes. SARS‐CoV‐2 was found to be extremely stable over a wide range of pH values. The researchers commented that SARS‐CoV‐2 can be highly stable in a favourable environment but is susceptible to standard disinfection methods. These results re‐emphasise the importance of following proper hand and respiratory hygiene practices, as well as social distancing and effective surface cleaning.

Cleaning and disinfection of surfaces

Studies on efficacy of biocide substances against SARS‐CoV‐2 on surfaces are now starting to become available. They seem to support initial indications from different sources that this virus is not especially resistant to common biocides. This means that there are many options available for surface decontamination and good hygiene can help to contain the spread of this terrible disease. Employees in food processing facilities should continue to follow good food hygiene practices. This is however a good time to review and verify that you have the correct cleaning and sanitising procedures and frequencies in place.

SARS‐CoV‐2 is an enveloped virus with an internal nucleocapsid. Disrupting the lipid envelope matrix layer will inactivate the genetic material. In terms of routine cleaning and disinfection programmes for contact and processing equipment, they should follow good hygienic practice and include a disinfectant product capable of inactivating viral contaminants (Table 1)[4] . The disinfecting agent's viricidal efficacy must comply with BS EN 14476. Whilst the standard does not include the recently identified SARS‐CoV‐2, it does contain Rotavirus, an encapsulated virus. Because a virus is not alive and does not consume nutrients, respire or reproduce unless in a host, it has its own standard and is not included in bacterial tests, such as BS EN 1276 & 13697. As with bacteria, cleaning is the most effective method of contaminant control. Fogging of disinfectant can be considered as a supplementary control measure[4] .

Table 1. Generic products for inactivation of coronaviruses[4]
ALCOHOL BASED available as a ready to use solution or a pre impregnated wipe based on 70% Propyl alcohols. The product needs verified viricidal efficacy under BS EN 14476
PERACETIC ACID based (foaming) – an OPC disinfectant containing at least 250ppm PAA at 1% v/v
PERACETIC ACID 5 and 15% w/w concentrates suitable for CIP. The products have verified viricidal efficacy under BS EN 14476
SODIUM HYPOCHLORITE solutions typically 14–15% delivering 1,000ppm free Chlorine
HYDROGEN PEROXIDE Only useable as a stabilised solution often in a ready to use trigger spray based on Hydrogen Peroxide, stabilised with ionic silver (other methods may leave a residue) and a suitable shelflife at ambient temperatures. The product needs verified viricidal efficacy under BS EN 14476.
IN‐SITU GENERATION e.g. hypochlorous acid (electrolysis of a brine solution), chlorine dioxide and Ozone. Each of these can demonstrate viricidal efficacy, however they require suitable generation equipment and monitoring systems for effective control.

Cleaning outside food production areas

Although not a direct food safety issue, enhanced cleaning of frequently touched surfaces in areas outside production areas, such as offices, may be required to prevent person to person spread of Covid19. Particular focus is needed on high risk communal areas, such as break rooms, locker rooms, toilets, first aid areas and surfaces like door knobs, hand rails, telephones, taps, electronics etc. Some critical members of the facility's technical and operational team, such as NPD and supply chain members, may not be based in the factory. If such key staff go absent this could potentially impact food safety capability.

Food businesses closed or in hibernation

We live in a time of contradiction; some food businesses have never been busier, while others are struggling to keep afloat. Due to hoarding, retailers have seen high sales figures more akin to Christmas and whereas the industry prepares all year for Christmas, this uplift has occurred at a couple of weeks’ notice, stressing supply chains and resources. Conversely what a dreadful time we have seen in the food service sector with restaurants, hotels and pubs closing their doors to the public. Some are surviving by converting to takeaways and using on‐line platforms.

The movement from a restaurant to a takeaway has its own potential food safety risks. Management might not be familiar with additional food safety controls, such as ensuring allergen labelling and communication is clear. Food businesses may need to amend and update their food safety management systems if a review of new activities identifies additional hazards that require control measures. Thought should be given to how the business can ensure the correct storage temperatures of hot and cold food are maintained until they are handed over to the customer.

Those that have closed restaurants need to ensure they take the right precautions when closing and then the right food safety start up precautions so they are safe when they reopen. Has food been stored under the correct conditions, have pests been excluded from the premises and has an effective sanitisation programme been carried out before reopening to eliminate any other hazards, such as Legionella?

Personal protective equipment (PPE )

Those working in the food sector have to consider the use of PPE. The wearing of face masks by food handlers could introduce an additional potential food safety risk. There is always a temptation for a food handler to touch and readjust a face mask. They can be very uncomfortable to wear. Adjusting a face mask could bring their hands into contact with their face and risk the spread of Staphylococcus aureus , which may be present in the nose and mouth, onto food via their hands.

It is vital that good standards of personal hygiene are maintained by food handlers to prevent food poisoning. Contaminated hands will spread bacteria around a food preparation area quickly. That is why it is essential to wash your hands after touching your face. I believe the wearing of face masks has the potential to increase this risk unless it is managed very carefully. Under normal circumstances, it is usual practice to wear a mask in some food industry sectors for occupational health reasons.

There is no need for food workers to wear gloves to protect against the virus; it is perfectly acceptable to prepare and handle food with bare hands provided proper hand‐washing procedures are in place.

Normal fitness to work procedures operated in food businesses should ensure that infected workers do not handle food.

Food business operators should ensure that staff are aware of the COVID‐19 situation and the advice being given by the HSE in relation to symptoms, social distancing, restricted movement, self‐isolation and travel.

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Conclusions

Hindsight is the only exact science. Only once this pandemic ends will we be able to fully assess the health, social and economic impact of this global disaster and we should then be able to learn lessons in terms of public health and impact on the global food supply network for any future similar pandemics.

In the meantime in our legitimate concern to feed the nation and provide food security, we should be careful that in our haste to provide this much needed food, we do not inadvertently compromise food safety. The management of the COVID‐19 situation, decision making, communication, implementation and the review of effectiveness of new and existing measures all need to be carefully organised and controlled.

The IFST is continuously monitoring and responding to this outbreak. It has created a COVID‐19 Advisory Group and a COVID‐19 Knowledge Hub to consolidate advice, practical guidance and links to resources to support individuals, smaller food businesses and larger food operations.

更新日期:2020-05-28
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