The UK Health Security Agency (UKHSA) has declared a national outbreak of salmonella food poisoning after one person died and 207 others fell ill. Because nothing says 'fun weekend' like a collective bout of foodborne illness.
While the source isn't confirmed, imported eggs or products containing them are the leading suspects. Evidence also suggests people caught the bug while eating out, not at home - so your home cooking is probably safe, but that trendy café might be a gamble.
Salmonella are a family of bacteria that live harmlessly in animal digestive tracts - cattle, pigs, and chickens - which is why eggs and poultry are common culprits. You can get infected by eating contaminated food that isn't cooked properly, coming into contact with infected animals, or cross-contaminating raw and cooked food in your kitchen. Symptoms include stomach cramps, diarrhoea, vomiting, or fever, typically developing 12 to 72 hours after infection. Most people recover on their own, but older adults, babies, and immunocompromised individuals face higher risks and may need hospital care with fluids and antibiotics.
Prevention is straightforward: cook eggs and other food thoroughly, wash your hands before preparing food, after using the bathroom, and after touching animals. The UKHSA's standard advice remains unchanged - thoroughly cooked eggs handled hygienically shouldn't pose a risk.
Of the 207 cases, 199 are in England, including 47 in London and 38 in Yorkshire and Humber. Scotland has six, Wales one, and Northern Ireland one. Whole-genome sequencing revealed the bacteria are closely related, with only a few DNA differences, indicating a common source. Genetic testing suggests similarities with a previous outbreak linked to imported eggs.
UKHSA experts interviewed 114 people; 24 cases had links to five unnamed businesses, with 11 reporting eating egg-containing dishes. These premises may use eggs from multiple suppliers, including imported ones. The UKHSA says there's no identified link to UK-produced eggs or poultry.
Jacquelyn McCormick of the Food Standards Agency reiterates that thoroughly cooked eggs are safe. Infants, young children, pregnant women, and older adults should only eat runny or raw eggs if they have a British Lion mark or are produced under the Laid in Britain scheme. Immunocompromised people should follow their doctor's advice.
Dr Kathleen O'Reilly at the London School of Hygiene and Tropical Medicine suggests checking food hygiene ratings when choosing eateries. Dr Charlotte Hammer at the University of Cambridge notes that vaccinating commercial hens against common salmonella strains since the mid-1990s has been a 'major public health success.' The British Lion Scheme, launched in 1998, requires strict codes including hen vaccination and traceability.
Paul Wigley, professor at Bristol Veterinary School, points out that the UK imports many eggs and egg products, and salmonella could be present because exporting countries may not use the same controls. Mark Williams, chairman of the British Egg Industry Council, advises food businesses importing eggs to verify vaccination information and food safety checks.
Health experts still need to confirm eggs as the source, trace where they came from, and then limit further infections. This is tricky because imported eggs often come from mixed sources. The UKHSA has alerted other countries to check for genetically similar infections. While salmonella outbreaks occur yearly, one linked to a single source causing hundreds of illnesses is relatively unusual - so scientists will examine what led to this situation. In the meantime, maybe give your eggs an extra minute in the pan.