Food Poisoning Outbreaks UK: 2026 Facts, Data & Key Insights

What Is a Food Poisoning Outbreak?

A food poisoning outbreak is defined as two or more linked cases of illness from a common food source. In the UK, foodborne outbreaks are investigated by UKHSA and its devolved equivalents in Wales (Public Health Wales), Scotland (Public Health Scotland), and Northern Ireland (Public Health Agency Northern Ireland), working alongside the Food Standards Agency, Food Standards Scotland, and local authorities.

Outbreak investigation involves identifying the cases, linking them through epidemiological analysis, tracing the common food vehicle, and taking action to remove contaminated food from the supply chain and prevent further cases. Modern whole genome sequencing (WGS) has dramatically improved outbreak investigation — allowing investigators to match bacterial strains between patient samples and food products with high precision. For the broader context, see our Food Poisoning Statistics UK guide.

Key Facts & Figures (Overview)

• An average of 2,133 food safety incidents were recorded annually in England, Wales, and Northern Ireland between 2019/20 and 2023/24, ranging from 2,478 in 2019/20 to 1,837 in 2023/24.
• More than half of all foodborne illness outbreaks in the UK are associated with catering establishments including restaurants, pubs, cafes, and care homes.
• In 2024, UKHSA investigated five major STEC outbreaks involving 467 cases, nine Campylobacter outbreaks (122 affected), seven Salmonella outbreaks (304 affected), and seven Listeria outbreaks (44 confirmed cases).
• The largest 2024 outbreak was a STEC O145 outbreak linked to salad leaves — 196 confirmed cases, 49% hospitalised, 2 deaths.
• The largest 2024 Campylobacter outbreak involved 61 cases from chicken liver parfait served at a stadium event.
• A quarter of all food safety incidents over 2021/22–2023/24 involved microorganisms with potential to cause illness — including STEC, Listeria, and Salmonella.
• Eating out is responsible for an estimated 37% of foodborne norovirus cases; takeaways 26% — making commercial food premises the setting for the majority of food-associated norovirus outbreaks.
• Norovirus outbreaks in care homes during winter 2024/25 reached the highest levels of norovirus activity since weekly reporting began in 2014 (February 2025 data).
• In 2024, three Campylobacter outbreaks occurred specifically in care home settings, with five of the nine outbreaks linked to liver products.
• Seven Salmonella outbreaks in 2024 affected 304 people — vehicles included red meat, tomatoes, and eggs served at restaurants.

How Outbreaks Are Investigated in the UK

The UK has one of the most sophisticated foodborne outbreak surveillance systems in the world. The key components are:

Laboratory reporting — clinical laboratories report confirmed cases of notifiable foodborne pathogens (including Campylobacter, Salmonella, STEC, and Listeria) to UKHSA via the Second Generation Surveillance System (SGSS).

Cluster detection — statistical analysis of surveillance data identifies when case counts for a particular pathogen or strain exceed expected background levels, triggering investigation.

Whole genome sequencing — once a potential outbreak is identified, WGS is used to compare the genetic profiles of isolates from different patients and from food samples. Exact genetic matches confirm common-source transmission with a precision that older typing methods could not achieve.

Epidemiological investigation — standardised questionnaires are administered to cases to identify common food exposures. Hypothesis-generating (trawling) questionnaires are followed by analytical studies (case-control or cohort) where a suspected vehicle has been identified.

Food chain investigation — the FSA and local authorities trace the implicated food through the supply chain from consumer back to primary production, identifying where contamination occurred and taking action to remove affected products and address the underlying cause.

Root Cause Analysis — food businesses associated with outbreaks are required to submit root cause analyses to the FSA explaining how the contamination occurred and what corrective actions have been taken.

2024 UK Outbreak Summary

The following is a summary of the major foodborne outbreak investigations in England in 2024:

Campylobacter (9 outbreaks, 122 affected):

• Five outbreaks associated with liver products (pâté, parfait made from chicken or lamb liver)
• Three outbreaks in care home settings
• Six outbreaks linked to eating outside the home (pubs, restaurants, events)
• Largest outbreak: 61 cases from chicken liver parfait at a stadium
• No deaths; 5 hospitalisations

Salmonella (7 outbreaks, 304 affected):

• Salmonella Typhimurium: largest outbreak with 109 cases, traced to red meat
• Salmonella Blockley: 81 cases linked to tomatoes
• Salmonella Strathcona: 24 cases linked to tomatoes
• Two Salmonella Enteritidis outbreaks totalling 24 cases, linked to eggs served in restaurants
• Salmonella Anatum: 37 cases, source not identified

STEC (5 outbreaks, 362 affected in England):

• All five outbreaks caused by non-O157 STEC strains
• Largest: 196 cases of STEC O145 linked to salad leaves; 49% hospitalised; 7 developed HUS (kidney failure); 2 deaths
• Three further outbreaks caused by E. coli O26 (affecting 64, 56, and 13 people respectively), linked to specific food products
• One E. coli O103 outbreak with unknown source; 33 cases, 10 hospitalisations

Listeria (7 outbreaks, 44 confirmed cases):

• Sources identified for five outbreaks: smoked fish, garlic sausage, chocolate mousse, strawberry mousse, prepacked sandwiches
• Two outbreaks included cases in Wales as well as England
• Seven deaths associated with Listeria overall in 2024 (across outbreak and sporadic cases)

The Most Common Outbreak Settings

UKHSA outbreak data and FSA incident data consistently identify the same settings as most frequently associated with outbreaks:

Restaurants, pubs, and catering events — the most common single setting for outbreaks. Campylobacter in undercooked liver products, Salmonella from eggs and meat, and norovirus from infected food handlers are the most frequent patterns.

Care homes — a disproportionate share of the most severe outbreaks, due to the vulnerability of the resident population. Three of the nine 2024 Campylobacter outbreaks were in care homes.

Farms and agricultural events — petting farms and lambing events generated multiple outbreaks in 2024, including very large Cryptosporidium outbreaks (781 cases in one outbreak) and STEC outbreaks linked to direct animal contact.

Food supply chain — outbreaks linked to contaminated products distributed through retail including supermarkets and food service. The salad leaf STEC O145 outbreak and the smoked fish Listeria outbreaks illustrate how supply chain contamination can affect large numbers of people across wide geographic areas simultaneously.

Drinking water — a Cryptosporidium outbreak in South Devon in April 2024 linked to mains water affected hundreds of people, illustrating that even regulated water supplies can occasionally fail.

Seasonal Patterns in UK Outbreaks

UK foodborne outbreaks show consistent seasonal patterns that reflect the biology of different pathogens and the seasonal behaviour of the food supply chain:

Summer (June–September): The peak season for Campylobacter, Salmonella, and STEC O157. Barbecue cooking of poultry drives Campylobacter and Salmonella summer peaks. Farm visits and outdoor events drive STEC O157 in children. The largest stadium-linked Campylobacter outbreak in 2024 occurred during the outdoor events season.

Autumn and winter (November–March): The peak season for norovirus — winter 2024/25 reached the highest norovirus activity recorded since weekly reporting began in 2014. Non-O157 STEC strains, unlike O157, peak in autumn rather than summer — a pattern that became more significant as PCR testing revealed their true prevalence.

Spring: Elevated Cryptosporidium risk from lambing events and petting farms, as demonstrated by multiple April 2024 outbreaks linked to these settings.

Outbreak Investigation: Recent Developments

The UK's outbreak investigation capability has been significantly enhanced by several developments:

PCR diagnostic testing — the widespread adoption of PCR testing in frontline NHS laboratories has dramatically increased the detection of non-O157 STEC, Norovirus, and other pathogens previously missed by culture-based methods. Non-O157 STEC cases have nearly tripled since 2019, largely reflecting improved detection.

Whole genome sequencing (WGS) — the FSA and UKHSA have invested substantially in WGS as a routine outbreak investigation tool. WGS enabled the rapid identification and confirmation of the STEC O145 salad leaf outbreak in 2024, allowing the source to be traced quickly and the implicated products recalled.

FSA Food Industry Liaison Group — increased membership to 40 organisations in 2024/25 improves the speed with which industry can be engaged during outbreak investigations and the quality of Root Cause Analysis information the FSA receives.

Expanded NFCU powers — the National Food Crime Unit received expanded powers in 2025, including the ability to apply for and execute search warrants, improving the investigation of criminal food fraud that can contribute to contamination events.

The Undercount Problem: Most Outbreaks Are Never Detected

The formally investigated outbreaks discussed in this guide represent only a fraction of the true number of foodborne illness clusters that occur in the UK each year. The vast majority of food poisoning outbreaks are never detected, investigated, or reported because:

• Most people with mild food poisoning do not seek medical attention
• Of those who do, many are not tested for specific pathogens
• Even where cases are diagnosed, the link between multiple cases and a common food source may not be made — particularly for small clusters affecting only a few people
• Norovirus in particular generates enormous volumes of foodborne illness with very few formally investigated outbreaks relative to its true burden

The FSA estimates 2.4 million foodborne illness cases per year in the UK — of which only a tiny fraction are ever connected to a formally investigated outbreak. The iceberg of undetected illness vastly exceeds the visible tip of investigated cases.

Written by Food Safety Experts

This guide was produced by the team at Food Hygiene Certificate, a UK provider of RoSPA-approved and CPD-accredited online food hygiene training. The pathogens and settings featured in this guide's outbreak data — Campylobacter in poultry, Salmonella in eggs and meat, STEC in produce and beef, Listeria in ready-to-eat foods — are all covered in depth in our food hygiene courses at Level 1, 2, and 3. For the full UK food poisoning picture, see our Food Poisoning Statistics UK guide, and for pathogen-specific data see our guides to Campylobacter, Salmonella, E. coli, Norovirus, and Listeria.

Sources & References

• UKHSA – Campylobacter Data 2015 to 2024 (June 2025)
• UKHSA – Shiga Toxin-Producing E. coli Cases Rise in England (July 2025)
• FSA – Annual Report of Incidents, Resilience and Prevention 2024/25
• Food Safety News – Early 2025 UK Data Shows Continued Rise in Infections (July 2025)
• Food Safety News – United Kingdom Saw Outbreaks Rise in 2023 (December 2024)
• UK Food Security Report 2024: Theme 5 – Food Safety