Salmonella Outbreak Investigation Continues into Rare Strain Affecting Dozens
Health authorities are continuing their investigation into an unusual Salmonella outbreak that affected more than 50 people across the United Kingdom in 2024, according to multiple media outlets. The UK Health Security Agency (UKHSA) has been leading efforts to identify the source of the rare Salmonella Blockley strain, which resulted in multiple hospitalizations last summer.
Between July 27 and August 24, 2024, officials documented 54 cases spanning three nations within the UK: 36 in England, 11 in Scotland, and 7 in Wales. The outbreak’s scope prompted the formation of a specialized incident management team comprising representatives from Public Health Scotland, Public Health Wales, the Public Health Agency in Northern Ireland, the Food Standards Agency (FSA), and Food Standards Scotland (FSS).
Those affected ranged widely in age, from just two years old to 85, with the highest concentration of cases appearing in people aged 50 to 59. Of particular concern was the hospitalization rate, with 10 of the 21 patients with available medical information requiring hospital treatment, an unusually high proportion that highlighted the outbreak’s severity.
The Salmonella Blockley strain represents an uncommon variant within the broader Salmonella family. While it causes typical Salmonella symptoms including diarrhea, stomach cramps, and fever, medical literature has documented some unusual characteristics of this particular strain. A 2006 case report published in a medical journal described a previously healthy young man who developed persistent arthritis following Salmonella Blockley infection, with symptoms continuing for up to a decade.
Scientific research has also indicated that Salmonella Blockley has demonstrated high rates of multi-drug resistance, potentially complicating treatment in severe cases. This particular strain is more frequently observed in East Asia and the United States, making its appearance in the UK especially noteworthy for epidemiologists.
While most Salmonella outbreaks are linked to specific food sources, investigators have thus far been unable to identify the origin of this cluster of infections. Salmonella Blockley is primarily associated with chicken and eggs, though it can also contaminate other foods such as smoked eel and vegetables. The absence of a clear pattern of international travel among patients suggests the contamination occurred within domestic food supply chains.
Adding to the complexity of the investigation, genetically similar strains of Salmonella Blockley have been identified in one European country, with possible cases appearing in another. This pattern suggests involvement of an international supply chain, though the specific product or ingredient remains elusive.
The European Centre for Disease Prevention and Control reported an increase in Salmonella Blockley cases during 2023, with 83 cases documented – the highest number recorded in the past decade. Authorities have not established whether this broader increase is directly connected to the UK outbreak, however.
The UKHSA initiated a national-level investigation due to several concerning factors: the number of infected individuals, the demographic profile showing higher risk among older adults, and the possibility of an internationally distributed vehicle of infection.
The investigation’s meeting notes, only recently made public, acknowledge that the source of the outbreak remains “unknown” despite extensive testing and contact tracing. While no new cases have been reported since the initial cluster, a UKHSA spokesperson confirmed that the investigation remains active.
Salmonella infections typically resolve within a week with supportive care like maintaining adequate hydration, though antibiotics may be necessary for severe cases, particularly in vulnerable populations such as infants, elderly individuals, or those with compromised immune systems.
Public health officials have continued to emphasize the importance of food safety practices to prevent Salmonella infections, including thorough cooking of meat and poultry, proper handling of eggs, and careful washing of produce.
Pork Scratchings Recalled by UK Grocery Retailer
Grocery chain Lidl Great Britain is voluntarily recalling Sol & Mar Chicharricos BBQ Pork Scratchings due to potential Salmonella contamination.
The recall notice did not specify how the potential for Salmonella contamination was discovered or how widely the recalled product was distributed in the United Kingdom.
- Product – Sol & Mar Chicharricos BBQ Pork Scratchings
- Size – 100 grams
- Best Before Dates – August 5, 2025; August 6, 2025; August 7, 2025; August 8, 2025; August 10, 2025; August 11, 2025; August 12, 2025
The company has asked customers to discontinue use and return the product to the nearest store for a refund.
Commenting on this article, the nation’s leading Salmonella lawyer said, “Salmonella is one of the most frequent causes of foodborne illness each year. Although it typically causes uncomfortable gastroenteritis, it can lead to additional symptoms such as bacteremia and or fever. Any consumer who believes they have been infected with Salmonella should seek medical care.”
