Large outbreak of group B invasive meningococcal disease in young adults in South East England, March 2026 - PMC Skip to main content An official website of the United States government Here's how you know Here's how you know Official websites use .gov A .gov website belongs to an official government organization in the United States. Secure .gov websites use HTTPS A lock ( Lock Locked padlock icon ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites. Search Log in Dashboard Publications Account settings Log out Search… Search NCBI Primary site navigation Search Logged in as: Dashboard Publications Account settings Log in Search PMC Full-Text Archive Search in PMC Journal List User Guide PERMALINK Copy As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsement of, or agreement with, the contents by NLM or the National Institutes of Health. Learn more: PMC Disclaimer | PMC Copyright Notice Euro Surveill . 2026 Apr 16;31(15):2600288. doi: 10.2807/1560-7917.ES.2026.31.15.2600288 Search in PMC Search in PubMed View in NLM Catalog Add to search Large outbreak of group B invasive meningococcal disease in young adults in South East England, March 2026 Jessica I’Anson Jessica I’Anson 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Jessica I’Anson 1 , Charlotte Anderson Charlotte Anderson 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Charlotte Anderson 1 , Shona Arora Shona Arora 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Shona Arora 1 , Ray Borrow Ray Borrow 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Ray Borrow 1 , Neil Bray Neil Bray 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Neil Bray 1 , Helen Campbell Helen Campbell 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Helen Campbell 1 , Colin NJ Campbell Colin NJ Campbell 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Colin NJ Campbell 1 , Meera Chand Meera Chand 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Meera Chand 1 , Stephen A Clark Stephen A Clark 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Stephen A Clark 1 , Paul Crook Paul Crook 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Paul Crook 1 , Obaghe Edeghere Obaghe Edeghere 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Obaghe Edeghere 1 , Stephen Glass Stephen Glass 2 East Kent Hospitals University NHS Foundation Trust, Ashford, United Kingdom Find articles by Stephen Glass 2 , Anjan Ghosh Anjan Ghosh 3 Kent County Council, Maidstone, United Kingdom Find articles by Anjan Ghosh 3 , Natalie Groves Natalie Groves 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Natalie Groves 1 , Florence Halford Florence Halford 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Florence Halford 1 , Kirsty Hewitt Kirsty Hewitt 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Kirsty Hewitt 1 , Susan Hopkins Susan Hopkins 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Susan Hopkins 1 , Rachael Hornigold Rachael Hornigold 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Rachael Hornigold 1 , Reece Jarratt Reece Jarratt 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Reece Jarratt 1 , Merav Kliner Merav Kliner 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Merav Kliner 1 , Nefeli Kouppa Nefeli Kouppa 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Nefeli Kouppa 1 , Shamez N Ladhani Shamez N Ladhani 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom 4 St George’s University, London, United Kingdom Find articles by Shamez N Ladhani 1, 4 , Jay Lucidarme Jay Lucidarme 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Jay Lucidarme 1 , Shobha Luxmi Shobha Luxmi 2 East Kent Hospitals University NHS Foundation Trust, Ashford, United Kingdom Find articles by Shobha Luxmi 2 , Martin CJ Maiden Martin CJ Maiden 5 University of Oxford, Oxford, United Kingdom Find articles by Martin CJ Maiden 5 , Eve Matthews Eve Matthews 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Eve Matthews 1 , Rachel Mearkle Rachel Mearkle 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Rachel Mearkle 1 , Charlotte Mirrielees Charlotte Mirrielees 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Charlotte Mirrielees 1 , Jaime Morgan Jaime Morgan 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Jaime Morgan 1 , Samuel Moses Samuel Moses 2 East Kent Hospitals University NHS Foundation Trust, Ashford, United Kingdom Find articles by Samuel Moses 2 , Rich Myers Rich Myers 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Rich Myers 1 , Grace Oswald Grace Oswald 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Grace Oswald 1 , Steven Riley Steven Riley 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Steven Riley 1 , David J Roberts David J Roberts 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by David J Roberts 1 , Charlene MC Rodrigues Charlene MC Rodrigues 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom 6 Imperial College Healthcare NHS Trust, London, United Kingdom 7 London School of Hygiene and Tropical Medicine, London, United Kingdom Find articles by Charlene MC Rodrigues 1, 6, 7 , Clare Sawyer Clare Sawyer 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Clare Sawyer 1 , Matthew Strutt Matthew Strutt 2 East Kent Hospitals University NHS Foundation Trust, Ashford, United Kingdom Find articles by Matthew Strutt 2 , Ed Waller Ed Waller 8 Kent and Medway Integrated Care Board (ICB), Maidstone, United Kingdom Find articles by Ed Waller 8 , William Welfare William Welfare 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by William Welfare 1 , Trish Mannes Trish Mannes 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom Find articles by Trish Mannes 1 ; on behalf of the Incident Management Team 9 Author information Article notes Copyright and License information 1 United Kingdom Health Security Agency (UKHSA), London, United Kingdom 2 East Kent Hospitals University NHS Foundation Trust, Ashford, United Kingdom 3 Kent County Council, Maidstone, United Kingdom 4 St George’s University, London, United Kingdom 5 University of Oxford, Oxford, United Kingdom 6 Imperial College Healthcare NHS Trust, London, United Kingdom 7 London School of Hygiene and Tropical Medicine, London, United Kingdom 8 Kent and Medway Integrated Care Board (ICB), Maidstone, United Kingdom 9 Members of the Incident Management Team are listed under Acknowledgements Correspondence: Jessica I’Anson ( [email protected] ) Received 2026 Apr 1; Accepted 2026 Apr 15. This article is copyright of the authors or their affiliated institutions, 2026. This is an open-access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0) Licence. You may share and adapt the material, but must give appropriate credit to the source, provide a link to the licence, and indicate if changes were made. PMC Copyright notice PMCID: PMC13090753 PMID: 42141888 Abstract An unusually large outbreak of invasive meningococcal disease affecting young adults occurred in South East England between 13 and 18 March 2026, with 21 confirmed cases including two fatalities. Thirteen cases were university students and 19 had attended the same nightclub over a 3-day period. The outbreak strain was a distinct genome within the previously seen type B: P1.12–1,16–183: F1–5: ST-485 (cc41/44). Over 13,000 chemoprophylaxis doses and 11,000 meningococcal B vaccinations were provided to possible contacts. Keywords: meningococcal disease, vaccines and immunisation, Neisseria meningitidis, public health, infectious diseases, invasive meningococcal disease, outbreak, epidemiology, vaccination, vaccine preventable diseases, Immunisation, Meningococcal, bacterial infections, outbreak control Invasive meningococcal disease (IMD) caused by Neisseria meningitidis can present as meningitis and/or sepsis with rapid onset and a high case fatality [ 1 ]. In England, suspected cases of acute meningitis or sepsis are legally notifiable by clinicians to public health [ 2 ]. In mid-March 2026 in South East England, an unprecedented outbreak of IMD with 21 cases triggered a large-scale, multi-sectorial response. Here, we describe the epidemiology and microbiological findings of the outbreak investigation and the public health measures taken to prevent onward transmission. Outbreak identification On 13 March 2026, the United Kingdom Health Security Agency (UKHSA) South East Health Protection Team (SEHPT) were notified of a suspected case of IMD in Canterbury, Kent, England. Additionally, the International Health Regulations National Focal Point of France informed UKHSA of a case exposed in Canterbury and identified in France. This was followed by a rapid sequence of notified cases from the same city over subsequent days, including two deaths. A SEHPT escalation meeting was held on the evening of 14 March followed by a national incident management team (IMT) meeting early on 15 March 2026, when an outbreak was declared. Case definitions were developed ( Box ) and information on demographic, clinical and epidemiological characteristics of cases were obtained via interview with cases or a proxy. Box. Definitions for confirmed and probable cases a for the invasive meningococcal disease outbreak, South East England, 2026. Confirmed case A clinical diagnosis of meningitis, septicaemia or other invasive disease, and at least one of the following: Neisseria meningitidis isolated from a normally sterile site Gram-negative diplococci identified in a normally sterile site meningococcal DNA in a normally sterile site meningococcal antigen in blood, cerebrospinal fluid (CSF) or urine and an onset of infection since 1 March 2026 and an epidemiological link to the outbreak via the nightclub, University A, or close contact with another case. Probable case A clinical diagnosis of meningitis or septicaemia or other invasive disease where a doctor and/or microbiologist considers that meningococcal infection is the most likely diagnosis and an onset of infection since 1 March 2026 and an epidemiological link to the outbreak via the nightclub, University A or close contact with another case. a Based on case definitions in national guidance [ 2 ]. Epidemiology Between 13 March and 26 March 2026, 21 confirmed IMD outbreak cases were identified. Cases became unwell between 9 March and 16 March, with a peak on 13 March (five cases). All were hospitalised, nine required intensive care and two died (case fatality rate: 9.5%) ( Figure 1 ). More information on the timing of hospitalisation of cases can be found in the Supplementary Figure S1 . Figure 1. Epidemiological curve of invasive meningococcal disease outbreak cases a , Kent, South East England, March 2026 (n = 20 b ) a By case category: confirmed MenB with outbreak strain, (B:P1.12–1,16–183); confirmed MenB (strain underdetermined due to low bacterial loads in specimens). b Excludes one confirmed MenB outbreak strain case with missing onset date information. Open in a new tab The cases were aged 18–27 years (median age: 19 years), 11 were female and 10 were male; 13 were university students, 10 of whom attended the same university (‘University A’). Of the University A cases, eight lived on campus but in different flats. Almost all cases were linked to a local nightclub before illness onset; 19 of 21 cases attended between 5 and 7 March 2026. Of the two cases who did not attend the nightclub, one had contact with friends who had attended on 5 March (8 days before the case developed symptoms); the other had no known links to any attendees. However, as both lived on campus at University A, they may have been exposed via an asymptomatic carrier within the university population ( Figure 2 ). Figure 2. Network diagram of invasive meningococcal disease outbreak cases, by case category and with key exposures, Kent, South East England, March 2026 (n = 21) The diagram displays contexts attended by ≥ 2 cases (‘Nightclub’ and ‘University A’) and known direct and indirect links among cases and between cases and contexts, as defined in the Box . Additional contexts are omitted for clarity where connections to well-established contexts are shown; the diagram does not represent all links. Open in a new tab No newly identified cases linked to this outbreak have been reported to UKHSA since 18 March, and no case had an incubation period suggesting an exposure after 5 to 7 March, when most cases visited the nightclub. Microbiology All suspected and confirmed cases were investigated and managed at local hospitals. Where available, meningococcal isolates from blood cultures were sent to the national Meningococcal Reference Unit for PCR testing, as were whole blood and cerebrospinal fluid (CSF) samples. Neisseria meningitidis serogroup B was confirmed in 21 cases using blood and/or CSF samples: PCR only (n = 15 cases), culture and PCR (n = 5 cases), culture only (n = 1 case). Of the 21 cases, 18 had subtype P1.12–1,16–183 (three had indeterminate subtyping due to low bacterial loads). The first of the six positive cultures underwent whole genome sequencing (WGS), and analysis of the core genome (using pubMLST.org) identified the strain as sequence type 485 (ST-485) within clonal complex 41/44 (cc41/44). A further five isolates were found to be closely related to the first genome with four sharing the Life Identification Number (LIN) code 6_0_0_0_1_27_4_18_0_0_0_0_0 (no differences in the core genome (1,422 genes)) and one having a single gene difference [ 3 ]. There were 33 diverse sequences (LIN Code Group 6_0_0_0_1_27_4) detected from IMD cases since 2020, mainly in the UK. The sequence from the current outbreak is divergent from its closest relatives, all isolated since 2022, though similar levels of diversity are seen across this LIN code group ( Figure 3 ). Figure 3. Core genome multilocus sequence typing neighbour-joining tree containing all sequences within LIN code group 6_0_0_0_1_27_4, South East England and Europe, March 2020–2026 (n = 43) Phylogenetic tree based is based on conserved alleles, with branch lengths representing allelic differences. The sequences from the current outbreak are shown in red. All sequences are labelled with year and country of collection. Generated with sequence data available in PubMLST using MicroReact ( https://microreact.org/project/7Gf85GnXGYFk17s98PDfz6-bigsdb3010564868128673039002 ). Open in a new tab All cultured isolates were susceptible (by E-test) to rifampicin, ciprofloxacin and cefotaxime, with two isolates exhibiting reduced sensitivity to penicillin (minimum inhibitory concentration: 0.38 mg/L; cut-off: > 0.25 mg/L). The outbreak strain was predicted to be covered by both UK-licensed meningococcal B (MenB) vaccines (phenotypic and/or genotypic testing): Bexsero (4CMenB fHbp peptide 4, NHBA testing pending; GSK) and Trumenba (MenB-fHbp peptide 4; Pfizer). The vaccine reactivity of the outbreak strain is further described elsewhere [ 4 ]. Public health actions In line with national public health guidance [ 2 ], the SEHPT conducted contact tracing for all confirmed and probable cases. Close contacts were provided with public health advice and coordinated antibiotic prophylaxis to eliminate carriage of N. meningitidis and limit further spread. Mass antibiotic prophylaxis (oral ciprofloxacin 500 mg, single dose) was commenced within 6 h of outbreak declaration, initially targeting occupants of University A accommodation blocks where suspected cases were resident. As more suspected cases were detected, this expanded to all persons living on campus at University A, persons who attended the nightclub during 5–15 March, and senior students in four secondary schools where suspected cases had been identified, in addition to close contacts. As of 30 March 2026, over 13,000 people had received antibiotic chemoprophylaxis, not including those who received antibiotics via their general practitioner (GP). The SEHPT liaised with all affected educational and community settings to provide public health information. Local healthcare providers were alerted on 15 March and a national alert of the outbreak was published the same day [ 5 ], with further information communicated on 18 March to healthcare providers summarising the situation and recommendations. Meningococcal B vaccination with Bexsero was offered from 18 March to those offered antibiotic prophylaxis. As of 30 March 2026, over 11,000 people had received the first dose of Bexsero, not including those who received vaccination via their GP, and will be offered a second dose. Discussion The emergence of cases in this outbreak was unprecedented in both speed and size and garnered national and international media coverage. There were 15 cases in young adults reported within 48 h, whereas previous outbreaks of IMD among students have usually been limited to two to nine cases [ 6 ]. While the case fatality rate (9.5%) is similar to that of England overall in 2024–25 (8.2%) [ 7 ], the occurrence and rapidity of the two deaths serve as a reminder of the severity of IMD. No new cases linked to this outbreak have been reported since 18 March, suggesting the rapid roll-out of chemoprophylaxis, vaccination, communications and public advice helped prevent further spread. The primary drivers of this outbreak remain unclear but a combination of social and environmental factors, characteristics of the outbreak strain and changes in population immunity are likely to have contributed. This outbreak affected young adults, many of whom university students. This aligns with known IMD risk factors, including higher meningococcal carriage in this age group and living in close quarters. Between 2024 and 2025, most IMD cases in England were caused by serogroup B (313/378, 82.8%), the majority of which were in persons under 25 years of age (194/313, 62.0%) [ 7 ]. University students in particular have a 12-times (95% confidence interval: 4.7–28.7) higher risk of IMD than non-student peers [ 8 ]. Vaccination against serogroup B (MenB) was introduced in England from May 2015 as part of the routine infant immunisation programme [ 9 ]. None of the cases would have been eligible for MenB vaccination as all were born before 1 May 2015. The outbreak strain was identified as ST-485 within cc41/44, a large and diverse meningococcal group endemic in the UK that accounts for 40% of IMD cases [ 4 ]. ST-485 is currently the most common MenB ST in England and responsible for increasing proportions of MenB IMD since 2010, despite overall reductions in MenB IMD incidence in recent decades [ 10 , 11 ]. The wider P1.12–1,16–183 sublineage was previously identified as causing an IMD cluster in 2023, comprising two older adult cases from a different part of the country [ 10 ], as well as two more recent outbreaks (two adults in 2025; three children in 2026, both not related to this outbreak) since it emerged in 2020 (unpublished data). The outbreak strain is distinct and is ca 90 genes from its closest ancestors; further work is needed to characterise these differences and their significance to meningococcal virulence. To better understand the dynamics of this outbreak, further studies are planned: a population seroprevalence study to estimate immunity against the outbreak strain; a retrospective cohort study to investigate risk factors for transmission within the nightclub and university; and a carriage survey to estimate prevalence of the outbreak strain among students in Canterbury and Medway. Conclusions A large and rapid outbreak of invasive meningococcal disease caused several cases of severe illness and two fatalities in South East England in March 2026. Despite the unprecedented nature of this incident, the public health response was fast, coordinated, multi-sectorial, and built on learning from the pandemic response. This outbreak illustrates the importance of a functioning and effective public health system that works closely with healthcare system partners. Ethical statement This work was conducted as part of routine outbreak investigation led by UKHSA and ethical approval was not required. Use of artificial intelligence tools None declared. Acknowledgements The authors would like to thank all members of the Incident Management Team, and all others involved in this response. In particular, we are grateful to the clinical teams managing cases, the South East Health Protection Team, the Meningococcal Reference Unit, Kent County Council, Kent and Medway Integrated Care Board, East Kent Hospitals University NHS Foundation Trust, Kent Community Health NHS Foundation Trust, the University of Kent, primary care providers, and all supporting educational, community and healthcare partners for their valuable input throughout the national incident response. We are also grateful to these members of the UKHSA incident response for their contributions: Emma Ackermann, Gayatri Amirthalingam, Richard Amlot, Nick Andrews, Carolina Arevalo, Amreet Battu, Tom Beattie, Charles Beck, Emma Bennett, Charlotte Bigland, Nadine Boczkowski, Carole Boulton, Natalie Bowman, Neil Bray, Amy Brewster-Brown, Sarah Brown, Isabel Bryans, Helena Calixte, Holly Carter, Serena Carville, Andre Charlett, Kim Clark, Olly Clifton-Moore, Suzi Coles, Jenny Colyer, Gemma Comer, Will Cook, Rebecca Cordery, Michelle Cox, Catherine Crawford, Alexandra Czerniewska, Ursula Dalrymple, Jack Davies, Valerie Decraene, Abi Dosanjh, Andrew Earnshaw, Grace Eldridge, Eva Emanuel, Catherine Falconer, Billie Fogarty, Elinor Godfrey, Paula Goulden, Alice Graham, Christie Haggis, Nathan Hall, Victoria Hall, Chelsea Hargreaves, Lucy E Harries, Abbie Harrison, Liz Harvey, Ellen Heinsbroek, Helen Higgins, Helen Hillier, Carla Hobart, Hannah Holt, Helen Hughes, Miriam Hunt, Yves Hurley, Cherstyn Hurley, Thomas Inns, Tom Irving, Reece Jarratt, Karen Johnson, Kirsten Jones, Philippa Jones, Jacky Jones, Pawanvir Kaur, Louise Kibbey, Lydia Kimotho, Ellen Kirkwood, Artur Kocon, Connor Latour, Jamie Lopez, Gemma Lyness, George Mallon, Afia Manaf, Sema Mandal, Petra Manley, Tobias Martinsen, Angelique Mavrodaris, Tamyo Mbisa, Helen McAuslane, Luke Mcgeoch, Lynne McLaughlin, Amanda Merrifield, Jamie Morgan, Jack Moss, Sarah Mottershead, Vaishnavi Nanjundaswamy, Emma Newall, Jack Nicholls, Bethany Pace Bonello, Georgina Parr, Selina Patel, Lewis Peake, Nicola Pearce-Smith, Keshav Phakey, John Quirk, Mary Ramsay, Anne-Marie Read, Kathryn Robinson, Koren Sanderson, Jacinta Santos, Stephanie Shadwell, Mark A Shaw, Richard Shrubb, Henry E Simkins, Beth Smout, Rosamund Southgate, Kelly Stoker, Amy Thomas, Eliza Thompson, Amanda Todd, Juli Treacy, Roberto Vivancos, Amoolya Vusirikala, Helen Wallace, Melody Walters, Dale Weston, Brennan Winer, Laura Woodward, Jin-Min Yuan and Maria Zambon. Supplementary Data Supplement 26-00288_IANSON_Supplement.pdf (181.7KB, pdf) Authors’ contributions: Jessica I'Anson: Conceptualization, Data curation, Formal analysis, Investigation, Writing – original draft, Writing – review & editing. Charlotte Anderson: Conceptualization, Investigation, Supervision, Writing – original draft, Writing – review & editing. Shona Arora: Investigation, Writing – review & editing. Ray Borrow: Data curation, Formal analysis, Investigation, Writing – review & editing. Neil Bray: Investigation, Validation, Visualization, Writing – review & editing. Helen Campbell: Data curation, Investigation, Writing – review & editing. Colin NJ Campbell: Data curation, Investigation, Writing – review & editing. Meera Chand: Investigation, Writing – review & editing. Stephen A Clark: Data curation, Formal analysis, Investigation, Writing – review & editing. Paul Crook: Investigation, Writing – review & editing. Obaghe Edeghere: Investigation, Supervision, Writing – review & editing. Stephen Glass: Data curation, Formal analysis, Investigation, Writing – review & editing. Anjan Ghosh: Investigation, Writing – review & editing. Natalie Groves: Data curation, Formal analysis, Visualization, Writing – review & editing. Florence Halford: Investigation, Validation, Visualization. Kirsty Hewitt: Data curation, Investigation, Writing – review & editing. Susan Hopkins: Investigation, Supervision, Writing – review & editing. Rachael Hornigold: Data curation, Investigation, Writing – review & editing. Reece Jarratt: Data curation, Visualization, Writing – original draft. Merav Kliner: Investigation, Supervision, Writing – review & editing. Nefeli Kouppa: Data curation, Investigation, Visualization, Writing – review & editing. Shamez N Ladhani: Data curation, Formal analysis, Investigation, Writing – review & editing. Jay Lucidarme: Data curation, Formal analysis, Investigation, Writing – review & editing. Shobha Luxmi: Data curation, Investigation, Writing – review & editing. Martin CJ Maiden: Data curation, Investigation, Writing – review & editing. Eve Matthews: Formal analysis, Investigation, Visualization, Writing – review & editing. Rachel Mearkle: Data curation, Investigation, Writing – review & editing. Charlotte Mirrielees: Investigation, Writing – review & editing. Jaime Morgan: Data curation, Investigation, Writing – review & editing. Samuel Moses: Data curation, Formal analysis, Investigation, Writing – review & editing. Richard Myers: Data curation, Formal analysis, Investigation, Visualization. Grace Oswald: Data curation, Investigation, Visualization, Writing – review & editing. Steven Riley: Data curation, Investigation, Writing – review & editing. David J Roberts: Data curation, Investigation, Supervision, Writing – review & editing. Charlene MC Rodrigues: Data curation, Formal analysis, Investigation, Writing – review & editing. Clare Sawyer: Conceptualization, Investigation, Writing – original draft, Writing – review & editing. Matthew Strutt: Data curation, Formal analysis, Investigation, Writing – review & editing. Ed Waller: Investigation, Resources, Writing – review & editing. William Welfare: Investigation, Supervision, Writing – review & editing. Trish Mannes: Investigation, Supervision, Writing – review & editing. Conflict of interest: RB, SAC, and JL perform contract research on behalf of UKHSA for GSK, Pfizer, and Sanofi but receive no personal remuneration. SNL performs contract research for St George's University of London for vaccine manufacturers but receives no personal remuneration. All other authors declare no competing interests. Funding statement: Not applicable. Data availability Outbreak genomes have been shared via pubMLST, the open-access molecular typing and microbial genome diversity database. UKHSA and pubMLST identifiers are supplied in the Supplementary Materials . References 1. Parikh SR, Campbell H, Gray SJ, Beebeejaun K, Ribeiro S, Borrow R, et al. Epidemiology, clinical presentation, risk factors, intensive care admission and outcomes of invasive meningococcal disease in England, 2010-2015. Vaccine. 2018;36(26):3876-81. 10.1016/j.vaccine.2018.02.038 [ DOI ] [ PubMed ] [ Google Scholar ] 2. UK Health Security Agency (UKHSA). Guidance for public health management of meningococcal disease in the UK. London: UKHSA; 2025. Available from: https://assets.publishing.service.gov.uk/media/69c25a5bbb0dfe55b83e4c2a/UKHSA-meningo-disease-guidelines-dec2025.pdf 3. Parfitt KM, Jolley KA, Unitt A, Bray JE, Colles FM, Harrison OB, et al. A Life Identification Number Barcoding (LIN Code) System for Neisseria meningitidis: high resolution multi-level typing of meningococci. bioRxiv. 2026:2026.03.03.708563. 4. UK Health Security Agency (UKHSA). Invasive Meningococcal Disease outbreak 2026: technical briefing 1. London: UKHSA. [Accessed: 24 Mar 2026]. Available from: https://www.gov.uk/government/publications/invasive-meningococcal-disease-outbreak-2026-technical-briefings/invasive-meningococcal-disease-outbreak-2026-technical-briefing-1 5. UK Health Security Agency (UKHSA). Cases of invasive meningococcal disease notified in Kent. London: UKHSA. [Accessed: 15 Mar 2026]. Available from: https://www.gov.uk/government/news/cases-of-invasive-meningococcal-disease-confirmed-in-kent 6. Soeters HM, McNamara LA, Blain AE, Whaley M, MacNeil JR, Hariri S, et al. Serogroup B Meningococcal Disease University Outbreak Group . University-based outbreaks of meningococcal disease caused by serogroup B, United States, 2013-2018. Emerg Infect Dis. 2019;25(3):434-40. 10.3201/eid2503.181574 [ DOI ] [ PMC free article ] [ PubMed ] [ Google Scholar ] 7. UK Health Security Agency (UKHSA). Invasive meningococcal disease in England: annual laboratory-confirmed reports for epidemiological year 2024 to 2025. London: UKHSA; 2025. Available from: https://www.gov.uk/government/publications/meningococcal-disease-laboratory-confirmed-cases-in-england-2024-to-2025/invasive-meningococcal-disease-in-england-annual-laboratory-confirmed-reports-for-epidemiological-year-2024-to-2025 8. Mandal S, Campbell H, Ribeiro S, Gray S, Carr T, White J, et al. Risk of invasive meningococcal disease in university students in England and optimal strategies for protection using MenACWY vaccine. Vaccine. 2017;35(43):5814-8. 10.1016/j.vaccine.2017.09.024 [ DOI ] [ PubMed ] [ Google Scholar ] 9. UK Health Security Agency (UKHSA). Meningococcal B vaccination programme for infants: information for healthcare practitioners. London: UKHSA; 2025. Available from: https://www.gov.uk/government/publications/meningococcal-b-vaccine-information-for-healthcare-professionals/meningococcal-b-vaccination-programme-for-infants-information-for-healthcare-practitioners 10. Loud E, Clark SA, Edwards DS, Knapper E, Emmett L, Ladhani S, et al. Serogroup B invasive meningococcal disease in older adults identified by genomic surveillance, England, 2022-2023. Emerg Infect Dis. 2024;30(5):1009-12. 10.3201/eid3005.231714 [ DOI ] [ PMC free article ] [ PubMed ] [ Google Scholar ] 11. Clark SA, Lucidarme J, Lekshmi A, Walsh L, Willerton L, Walker A, et al. The expansion of a group B invasive meningococcal ST-485 (ST-41/44 clonal complex) strain in England: 2010-2022. 16th EMGM Congress, European Meningococcal and Haemophilus Disease Society; 2023 2023 May 29–June 1; Dubrovnik, Croatia. Croatia: The European Meningococcal and Haemophilus Disease Society; 2023. [ Google Scholar ] Associated Data This section collects any data citations, data availability statements, or supplementary materials included in this article. Supplementary Materials Supplement 26-00288_IANSON_Supplement.pdf (181.7KB, pdf) Data Availability Statement Outbreak genomes have been shared via pubMLST, the open-access molecular typing and microbial genome diversity database. UKHSA and pubMLST identifiers are supplied in the Supplementary Materials . Articles from Eurosurveillance are provided here courtesy of European Centre for Disease Prevention and Control ACTIONS View on publisher site PDF (339.4 KB) Cite Collections Permalink PERMALINK Copy RESOURCES Similar articles Cited by other articles Links to NCBI Databases Cite Copy Download .nbib .nbib Format: AMA APA MLA NLM Add to Collections Create a new collection Add to an existing collection Name your collection * Choose a collection Unable to load your collection due to an error Please try again Add Cancel Follow NCBI NCBI on X (formerly known as Twitter) NCBI on Facebook NCBI on LinkedIn NCBI on GitHub NCBI RSS feed Connect with NLM NLM on X (formerly known as Twitter) NLM on Facebook NLM on YouTube National Library of Medicine 8600 Rockville Pike Bethesda, MD 20894 Web Policies FOIA HHS Vulnerability Disclosure Help Accessibility Careers NLM NIH HHS USA.gov Back to Top