UK Salmonella Outbreak Linked to Imported Eggs

The UK Health Security Agency has declared a national outbreak of salmonella food poisoning after one person died and hundreds more fell ill. Although not yet proven, imported eggs or dishes containing them are the leading suspects as to the cause. Evidence suggests people caught the bug while eating out, rather than at home, with catering and food services such as restaurants, cafes or take-aways likely to play a part.

## What is salmonella and how do you catch it? Salmonella are a family of bacteria that typically live harmlessly in the digestive tract of animals, including cattle, pigs, and chicken. The bacteria are shed in animal faeces. You can catch the bug by eating contaminated food that has not been cooked properly, drinking contaminated water, coming into contact with infected animals, or cross-contamination after mixing raw and cooked food in the kitchen.

## What are the symptoms and how to protect yourself? Signs to watch out for include stomach cramps, diarrhoea, vomiting, or fever. These usually develop between 12 and 72 hours after becoming infected. In most cases, people recover without further help, but older people, babies, and people with weakened immune systems are at greatest risk of severe disease. Cooking eggs and other food thoroughly can prevent infection. Other ways to protect yourself include washing your hands before preparing food, after using the bathroom, and after contact with animals.

## Where is the outbreak happening and what is being done? The majority of recent cases have been in England, including 47 in London and 38 in Yorkshire and Humber. There have been six cases in Scotland, one in Wales, and another in Northern Ireland. The Food Standards Agency has issued guidance to catering businesses on the storage and handling of eggs. Scientists used a type of comprehensive genetic fingerprinting called whole-genome sequencing, which revealed the bugs involved are all closely related. Tests show there are only a handful of differences in their DNA sequences, which indicate the infections are part of the same outbreak, with a common source.

The UKHSA has alerted other countries about this outbreak so they can check for any genetically similar infections. Local authorities will be carrying out tests on businesses that are likely to be involved as well as carrying out some opportunistic testing. Experts will also need to look at the whole supply chain, investigating where the eggs or egg products have been eaten, supplied, stored, and farmed, for example. Once they have enough information, an important step would be to limit further infections. The exact source and country of origin will need to be traced.