Poliovirus detected in routine sewage surveillance from Leeds, London and West Sussex – an update

A rapid communication has been published in Eurosurveillance (1) which provides an overview of the recent linked detections of Vaccine Derived Poliovirus Type 2 (VDPV2) in 5 countries in Europe: Spain, Poland, Germany, the United Kingdom (UK) and Finland.

This updates the latest findings for the UK published on 10 December 2024.

UK findings

Testing of sewage samples collected in November 2024 identified VDPV2 in one sample from East Worthing Sewage Treatment Works (STW), which covers some of West Sussex local authority and adjacent areas, 2 samples from Leeds Knostrop SWT, one sample from London Beckton SWT and one sample from London Crossness SWT. At that time, sampling at the sites where the VDPV2 was detected was increased to fortnightly to inform a timely investigation and any necessary response.

Testing of sewage samples in December detected VDPV2 from a single sample collected from London Beckton STW on 10 December. All other sites tested negative for poliovirus in December.

All sites (including all those with VDPV2 detections in November) had tested negative for poliovirus as of 23 January 2025.

Europe findings

The PV isolates found in the UK are genetically linked to a VDPV2 that has been widely circulating in several African countries in recent months, unrelated to any previous PV found in the UK. All strains detected from the 5 countries in Europe are genetically linked between them, classifying these isolates as circulating VDPV2 (cVDPV2) as per Global Polio Eradication Initiative (GPEI) requirements for VDPV classification and reporting.

To date, however, there is no evidence of community transmission in the UK and the risk to the public is low. UKHSA is coordinating the public health investigation and response to these detections with system partners at the national, regional and local level. Vaccine-derived PVs, such as the ones detected, have the potential to spread, particularly in communities where vaccine uptake is lower. On rare occasions it can cause paralysis in people who are not fully vaccinated. These latest findings are a timely reminder of the importance of local areas ensuring any children not fully up to date with their polio vaccinations have caught up.

These results highlight the value of sensitive and effective environmental surveillance established across England, led by UKHSA and the Medicines and Healthcare products Regulatory Agency (MHRA), for the early detection of PV importations which may then lead to community transmission.

Reference

1. ECDC. Detection of circulating vaccine-derived poliovirus type 2 (cVDPV2) in wastewater samples across Europe: a wake-up call, Finland, Germany, Poland, Spain, the United Kingdom, 2024 January 2025

SSIs in NHS hospitals in England: 2023 to 2024 annual report in summary

The latest annual report, summarising data submitted to the national Surgical Site Infection Surveillance Service by 189 NHS hospitals and 8 independent sector NHS treatment centres in England, has been published. The report presents SSI risk benchmarks for each of 17 surgical categories, trends in SSI incidence and variation among participating hospitals. It also includes risk-stratified SSI incidence including, for the first time, time to infection.

Surveillance data on 135,619 operations and 1,276 SSIs detected during inpatient stay or on readmission to hospital were submitted in 2023 to 2024 (1). The number of procedures submitted increased by 8.4% compared to the previous year, surpassing the pre-pandemic levels for the first time. NHS trusts performing surgery in any of 4 orthopaedic categories (hip replacement, knee replacement, reduction of long bone fracture and repair of neck of femur) are required to undertake surveillance of SSI for a minimum of one 3-month surveillance period per financial year. Trust-level SSI risk results for mandatory orthopaedic categories can be found as accompanying supplementary tables (2).

Among the main findings were that:  

• almost two-thirds of hospitals carried out continuous surveillance in hip and knee replacement categories (64.5% and 62.8%, respectively)
• in 2023 to 2024, one eligible trust did not meet the mandatory participation surveillance requirements, compared to 2 trusts in the previous year
• 10-year trends in the annual inpatient and readmission SSI risk varied by surgical category, with 8 out of 10 categories seeing overall decreases in SSI risk during this period
• year-on-year SSI risk has increased marginally for 9 out of 10 categories with at least 5 hospitals participating between 2022 to 2023 and 2023 to 2024
• there was an indication of elevated SSI risk among black patients undergoing reduction of long-bone fracture (Risk Ratio (RR) 2.96, 95% CI: 1.11 to 7.94) and some evidence of reduced SSI risk in Asian patients undergoing coronary artery bypass graft surgery (RR 0.75; 0.62 to 0.91)
• among SSIs with accompanying microbiology data, Enterobacterales continued to make up the largest proportion of isolates for both superficial SSIs (29.9%) and deep or organ and space SSIs (30.1%)
• the highest proportion of organ or space infections was in bile duct, liver or pancreatic surgery (69.2%), cranial surgery (51.5%) and large bowel surgery (48.9%)
• median time to infection across all categories was 16 days, ranging from 7 days for small bowel surgery to 25 days for knee replacement
• 2 trusts were identified as high outliers for the mandatory surveillance categories (both in repair of neck of femur category) in 2023 to 2024

References

1. UKHSA. Surveillance of surgical site infections in NHS Hospitals in England, April 2023 to March 2024 December 2024

2. UKHSA. Surgical site infections surveillance: NHS Trust tables April 2022 to March 2024 December 2024

Outbreak of Burkholderia stabilis associated with non-sterile ultrasound gel in the UK, 2024

The UK Health Security Agency (UKHSA) has worked with key stakeholders and partners, including the NHS and the Medicines and Healthcare products Regulatory Agency (MHRA), to investigate an outbreak of Burkholderia stabilis sequence type (ST) 1565 associated with non-sterile ultrasound gel use in healthcare settings.

Burkholderia stabilis (B. stabilis) is a member of the Burkholderia cepacia complex (Bcc). This is a group of Gram-negative bacteria that are widely found within the environment and are naturally resistant to many antibiotics. Bcc rarely cause infection but can cause severe infections in people with weakened immune systems and those living with cystic fibrosis. They are a recognised cause of contamination of aqueous-based medical and personal care products, such as ultrasound gel.

In October 2024, the UKHSA Antimicrobial Resistance and Healthcare Associated Infections (AMRHAI) reference laboratory identified a geographically dispersed cluster of B. stabilis ST1565 isolates. This included 3 isolates from a critical care unit in a hospital in England, where a suspected common exposure to ultrasound gel had been identified by the local Infection Prevention and Control (IPC) team. 

As of 16 January 2025, there were 6 confirmed and one probable case, with specimen dates between 4 July and 2 October 2024, in 4 regions across England. No cases were identified in Scotland, Wales or Northern Ireland. Cases were aged 11 to 79 years, with a median age of 68 years. Four cases were male. Five cases were from inpatient settings, including 3 confirmed cases from a critical care unit.

Two confirmed cases (29%) were considered to have clinically significant infections attributable to B. stabilis, where B. stabilis was thought to have caused infection by the clinical team and/or the patient received antibiotics to cover potential B. stabilis infection. However, establishing the contribution of B. stabilis on the patient’s condition was difficult as both cases were critically ill prior to the positive result.

Distribution of confirmed and probable cases by week of specimen date between 1 July 2024 and 16 January 2025 (n = 7), showing key dates and interventions in the UK, 2024

A multi-stakeholder Incident Management Team (IMT) was convened, led by UKHSA with representation from MHRA, devolved governments, clinical teams, NHS England and NHS Supply Chain, the Department of Health and Social Care (DHSC) and other representatives from the health and care sector. Through close partnership-working, a contaminated medical product was identified as the potential source.

As part of the investigation, UKHSA asked hospitals with cases to submit products to the UKHSA Food Water and Environment (FWE) laboratory. B. stabilis was recovered from multiple bottles (opened and unopened) of a non-sterile ultrasound gel product from different hospital sites. In addition, 5 cases (71%) had a documented exposure to ultrasound gel, further supporting the hypothesis that contaminated ultrasound gel product was the likely source. All ultrasound gel isolates were subsequently typed as ST1565.

The IMT conducted a risk assessment, including potential impact on product supply chain. UKHSA supported MHRA to engage and inform the manufacturer who undertook a voluntary recall, issuing a Field Safety Notice on 17 October 2024. This recall was extended on 7 November 2024 to include a second lot of the same product, and again on 20 December 2024 to include multiple lots of 2 further non-sterile ultrasound gel products from the same manufacturer.

The implicated ultrasound gel product was non-sterile and not intended for use in sterile procedures. This outbreak highlights the importance of appropriate use of ultrasound gel, and potential risk associated with these products. UKHSA has previously published guidance on the safe use of ultrasound gel in healthcare settings. The guidance outlines measures to reduce risk to patients associated with the use of non-sterile ultrasound gel and when to use sterile gel. In light of this outbreak, UKHSA has updated this guidance to reinforce recommendations for healthcare providers, clinicians and practitioners using ultrasound gel. UKHSA previously issued a National Patient Safety Alert to ensure alignment to this guidance and contents of this alert remain valid.

There have been no new confirmed cases since 2 October 2024. UKHSA will continue to follow up new cases and monitor for emerging clusters of B. stabilis. UKHSA would like to thank colleagues for their help and support in this investigation, particularly:

• clinical and IPC teams from affected NHS trusts
• MHRA
• DHSC
• UK devolved governments
• NHS Supply Chain
• NHS England
• all other individuals involved in the Incident Management Team and in supporting investigations

Infection reports in this issue

Group A Streptococcal infections: first update on seasonal activity in England, 2024 to 2025

Hepatitis C (England and Wales): 2022

Vaccine coverage reports in this issue

RSV maternal vaccination coverage in England: September 2024

RSV vaccine coverage report in older adults for catch-up cohorts in England: December 2024

Shingrix vaccine uptake report (adults eligible from September 2023 to August 2024 and vaccinated to the end of October 2024): England

Meningococcal ACWY (MenACWY) vaccine coverage for adolescents in England, academic year 2023 to 2024

Td/IPV vaccine coverage for the NHS adolescent vaccination programme in England, academic year 2023 to 2024

Quarterly vaccination coverage statistics for children aged up to 5 years in the UK (COVER programme): July to September 2024