What is salmonella, how does it spread and are eggs safe to eat?

A recent outbreak of salmonella has infected over 200 people in the UK, with one fatality and 34 hospitalizations reported. The source of the contaminated eggs was traced to imported eggs consumed in restaurants, according to the UK Health Security Agency.

Dr Malick Gibani, a clinical associate professor at Imperial College London, explained that salmonella is not a single bacterium but rather a group of bacteria causing infection in humans. Over 2,500 types exist, but a few are responsible for most infections in the UK. These bacteria commonly reside in contaminated animal products such as meat, dairy, and eggs, although other food items like chocolate, peanut butter, and cucumbers have also been implicated in outbreaks.

Salmonella can spread through various means, including contaminated water, contact with animals, person-to-person transmission, and poor food hygiene. Storing food improperly and failing to cook contaminated food thoroughly are additional risks. The bacteria cause gut infections, leading to gastrointestinal symptoms such as abdominal pain, diarrhea, vomiting, and fever. These symptoms typically appear within hours to days after consumption.

While most cases resolve without treatment in healthy adults, vulnerable groups like children, older adults, immunocompromised individuals, and those with underlying health conditions may experience more severe symptoms. In rare instances, salmonella can cause bloodstream infections, leading to severe sepsis-like illness, particularly in these high-risk groups.

Experts advise consumers to purchase eggs produced in the UK, which bear the red lion mark and have been vaccinated against salmonella. To minimize the risk of infection, it is crucial to cook eggs and dishes containing eggs thoroughly until both the yolk and white are firm, reaching a temperature of 71C. Additionally, avoid using cracked or broken eggs, and refrain from washing eggs before use, as this can increase the risk of contamination.

UK Health Security Agency (UKHSA) emphasizes the importance of public awareness and informed decision-making regarding salmonella consumption. While systems for protecting against salmonella are in place, no regime is entirely foolproof, as demonstrated by this latest outbreak. The UKHSA website offers valuable information for those seeking further guidance on salmonella prevention.