A potentially life-threatening serious gut infection is on the rise across England, with cases increasing by almost 50% in five years.
Cases of Clostridioides difficile (C. diff) infection in England rose from 22.2–33.3 cases per 100,000 people between 2020 and 2021 and 2024 and 2025, according to UK Health Security Agency (UKHSA) data. The 49.8% increase marks the highest incidence rate since 2011 and 2012, with 18,970 total cases reported in 2024 and 2025.
The upward trend has been recorded in both hospital-onset and community-onset cases and spans all age groups.
Dr Godwa, clinical research leader at Trialmed, notes that public perception often overlooks the main driver behind the increase: “People hear about C. diff outbreaks and assume it is about dirty hospitals, but the evidence tells a different story. Antibiotic use, not environmental cleanliness, is the single biggest driver of who develops this infection.”
Understanding C. diff and its drivers
C. diff is a bacterium that naturally inhabits the gut of some individuals without causing harm. However, when the balance of “good” bacteria in the bowel is disrupted, the bacterium can multiply rapidly and produce toxins. This can cause symptoms ranging from diarrhoea, fever, and stomach cramps to severe inflammation of the colon.
“Antibiotic overuse remains the core problem,” Dr Godwa added. “Every course of antibiotics, particularly broad-spectrum ones, wipes out protective gut bacteria and gives C. diff room to take hold.”
Antibiotics do not solely target the bacteria causing an illness; they can also eliminate large sections of the healthy gut microbiome that normally compete with C. diff for space and nutrients. Consequently, individuals are up to 10 times more likely to develop a C. diff infection while taking antibiotics and during the month after finishing a course, with longer treatment durations further increasing the risk.
Under UK prescribing classifications, broad-spectrum antibiotics in the Watch and Reserve categories carry a particularly high risk. “Certain antibiotics carry a particularly high risk, including clindamycin, cephalosporins, fluoroquinolones such as ciprofloxacin, and broad-spectrum penicillins, all of which can cause extensive disruption to gut bacteria,” Dr Godwa explained.
High-risk groups
While anyone currently taking or recently finished a course of antibiotics is at risk, UKHSA data and clinical evidence highlight specific high-risk populations
People aged over 65
Rates are highest among those aged 85 and over. “Older adults account for the vast majority of cases, with more than 80% of infections reported in the over-65 age group. This is largely down to a combination of weaker immune defences, more frequent antibiotic exposure through repeat courses for other infections, and greater contact with healthcare settings, all of which can increase the risk of C. diff taking hold,” Dr Godwa stated.
People with weakened immune systems
“Those with cancer, organ transplants, or taking immunosuppressant drugs are significantly more vulnerable to infection taking hold,” noted Dr Godwa. “A properly functioning immune system helps limit how much C. diff can multiply and how severe the resulting inflammation becomes, so when that response is suppressed by illness or medication, infections tend to progress further and recovery takes longer.”
Anyone with a previous C. diff infection
“Prior infection raises the risk of recurrence, with relapse occurring in around 20%–30% of patients, and that risk climbs to 40%–60% after a first recurrence,” Dr Godwa explained. “Recurrence happens for two main reasons: dormant spores left behind in the gut after the first infection can germinate again once conditions allow, or a person can be reinfected from a contaminated environment, and in most documented cases it is the original strain relapsing rather than a fresh infection.”
Preventive measures and patient advice
Dr Godwa highlights key steps to reduce the risk of C. diff infection and protect the gut microbiome: “Only take antibiotics when clinically necessary. Avoiding unnecessary antibiotics is the most effective way to protect the gut’s natural bacterial balance, because it is specifically the depletion of protective bacteria, and the bile acids and nutrients they help regulate, that creates the opening C. diff needs to establish an infection.”
“Where antibiotics are unavoidable, choosing a narrower-spectrum option and the shortest effective course limits the amount of collateral damage done to the microbiome. If you develop diarrhoea while or after taking antibiotics, that is a reason to contact a GP rather than stopping the tablets on your own.”
Dr Godwa advises patients currently taking antibiotics who develop diarrhoea or feel very unwell to speak with a doctor so they can adjust the treatment or investigate for C. diff.
Health officials continue to monitor the upward trend across England and stress the ongoing importance of antimicrobial stewardship to limit further increases in C. diff infections.