Dozens of people poisoned this year by salmonella-infected British eggs

Dozens of people have been poisoned after consuming British eggs contaminated with salmonella, an investigation has found, despite recent government assurances that the risk had been virtually eliminated.

At least 45 consumers have fallen ill since January this year in a major disease outbreak health officials have traced back to contaminated eggs and poultry farms. Salmonella can cause food poisoning and – in the most serious cases – can prove fatal. Public Health England (PHE), which monitors salmonella, is not aware of any deaths.

Despite outbreaks of this strain occurring for more than three years, the government has issued no public warnings about the safety of hens’ eggs. In 2017, the Food Standards Agency (FSA) told the public that it was safe for vulnerable people, including pregnant women and the elderly to eat raw, runny or soft-boiled eggs. At the time the head of the FSA said: “The risk of salmonella is now so low you needn’t worry.”

Internal records obtained by the Bureau of Investigative Journalism and the Guardian show that 25 egg-laying poultry flocks in the UK have tested positive for salmonella in 2019 so far, seven of them contaminated with the most serious strains of the bacteria. Two egg-packing factories – one that supplies leading supermarkets – have also been contaminated, records show.

Eggs produced by the infected poultry flocks were placed under restrictions, meaning they cannot be sold to the public and must be sent for processing to kill the bacteria or be disposed of – while birds from infected flocks were culled.

However, some contaminated eggs did reach the public, with PHE confirming that 45 people had become ill after eating eggs infected with salmonella since January. The exact route to the public is unclear.

The government records also reveal that in 2018, 28 flocks tested positive for salmonella, four of them with dangerous strains.

According to PHE a further 55 human cases prior to 2019 were also being linked to the outbreak.

The revelations come just two years after the Food Standards Agency (FSA) declared that almost all eggs produced in the UK were free of salmonella. A major health scare in the 1980s had led to warnings that vulnerable groups should not consume raw or lightly cooked eggs – or food containing them – because of the salmonella risk. The then junior health minister Edwina Currie sparked a public outcry after saying “most” British egg production was infected with salmonella.

But in 2017 the FSA lifted the advice, stating the presence of salmonella in eggs had been “dramatically reduced” and that “British Lion” eggs – which cover about 90% of UK egg production – were safe to eat.

Speaking at the time, the then FSA chair Heather Hancock said: “We are now saying if there is a British Lion egg, you’re safe to do that. The risk of salmonella is now so low you needn’t worry. And that’s true whether you’re a fit healthy adult, or whether you’re pregnant or elderly or young. It’s only people on strictly medically supervised diets who need to avoid those eggs.”

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PHE stated that it had been investigating this strain of salmonella for three years, despite the FSA clearing eggs for consumption.

Three farms supplying Kent-based egg company Fridays Ltd were among those found to be contaminated, with an egg-packing station run by the firm also testing positive for salmonella. The company has supplied egg and egg products to major supermarkets, according to their website.

It is understood that production at the packing factory was temporarily halted as a result of salmonella contamination this year.

The company, which produces 10m eggs a week, confirmed it had removed the farms from its supply chain and disinfected the factory. Fridays said in a statement: “Like all responsible UK egg farmers and egg packers, we carry out regular testing of our firms and those of our suppliers … Salmonella occurs naturally in the environment. However, with regular precautionary testing, vaccination of hens and rigorous control procedures, its prevalence in farming can be minimised.”

The timing of the revelations is awkward for the government as the prospect of a no-deal Brexit throws a spotlight on the UK’s farm hygiene, and food safety for consumers.

One of the sticking points in the negotiations is over a potential hard border in Ireland where animal products destined for the EU would be tested, to prevent infected products being imported or exported. The government is also facing rows over the potential for imports of animal products from countries with lower standards than the EU, such as chlorinated chicken from the US.

Salmonella bacteria is found in the guts of poultry and livestock. Birds and animals can be infected through feed, in hatcheries, or through faeces during transport to abattoirs, where slaughter and processing can also spread the infection. In humans, salmonella poisoning can be life-threatening, particularly in infants and the elderly.

Salmonella infection in eggs is a common cause of food poisoning in humans and can cause serious illness. In the case of poultry, there is a possibility of transmission of infection in or on eggs from both breeding and laying flocks. However, the industry has done a lot to minimise risks, and the introduction of regulations has further helped to improve the control and prevention of salmonella.

A Government spokesperson said: “We take the safety of the nation’s food extremely seriously. The Food Standards Agency and Animal and Plant Health Agency (APHA) are investigating and taking action to control this outbreak alongside industry, Public Health England and local authorities.”

The British Retail Consortium said: “Food safety remains a top priority for UK retailers and all UK sourced eggs are produced to the Lion code of practice. Retailers will comprehensively investigate any safety issues in our food supply and will take swift action as necessary.”