European Immunization Week 2025: Inequalities in immunisation against measles could contribute to outbreaks

Research just published on Eurosurveillance revealed inequalities in MMR (measles-mumps-rubella) vaccination, which may contribute to measles outbreaks and epidemics. A nationwide study in France found that vaccines were dispensed later for children from low-income families [1], while an investigation of a measles outbreak in Birmingham, United Kingdom (UK) [2] showed that people from deprived communities and some ethnic groups were more affected by the outbreak and were less likely to be vaccinated against the disease.

In the context of European Immunization Week, which every year raises awareness of immunisation to prevent diseases and protect life, these studies underscore the importance of taking social, economic and demographic factors into account to increase vaccination rates and protect both vulnerable groups and the wider population against vaccine-preventable diseases.

Measles is a highly contagious disease, and one infected person can infect nine out of 10 close contacts who have no immunity against it. It is preventable with the MMR vaccine, which is part of the routine immunisation schedule both in the UK and France, where it is offered in two doses.

New French vaccination mandate increased immunisation inequalities

The study in France sought to test the effectiveness of the updated national guidelines for measles vaccination, which set a target MMR vaccination rate at age 24 months of at least 95% for the first dose, and at least 80% for the second, with the recommended age of the first dose set at 12 months and the second at 16-18 months. These guidelines also increased the number of mandatory childhood vaccinations for preschool and primary school admission from three (diphtheria, tetanus and polio) to 11, which included the MRR vaccine. This updated schedule was adopted due to the high proportion of 2-year-olds and 3-year-olds in preschools. The nationwide study followed up on three birth cohorts (2015, 2017, 2019) with a total of 2.1 million children for 48 months to assess the timeliness of MMR vaccine dispensation, before and after it became mandatory in France (January 2018).

The study showed that among children vaccinated by healthcare providers in the community, the estimated vaccine coverage and timeliness of vaccination for both MMR doses improved moderately after these new mandates came into effect. However, full vaccination rates in the 2019 cohort remained clearly below the 95% target to achieve herd immunity as recommended by the World Health Organization (WHO), and vaccines were dispensed late for 33% in that cohort. Children of low-income families were also vaccinated later and less well protected against measles. They benefited less from the new mandate, which increased social inequalities in immunisation as a result.

Measles outbreak in Birmingham overwhelmingly affected most deprived areas

Meanwhile, the United Kingdom Health Security Agency (UKHSA)  investigated a large measles outbreak affecting over 400 people in Birmingham, describing the epidemiological situation of the first 6 months of the outbreak with a focus on its sociodemographic inequalities. These included describing inequalities in vaccination rates and among high-risk communities where efforts to control measles should be identified.

The investigation found that deprived communities and some ethnic groups were disproportionately affected by the outbreak. In total, 406 cases were reported during the first 6 months of the outbreak, with 78% occurring in Birmingham’s more deprived areas. Measles affected the ‘Black and Black British – any other Black background’ ethnic group the most, with 112.2 cases per 100,000 people. Most patients in the outbreak (89%) were unvaccinated. People from the ‘White’ ethnic group who had measles and were old enough to receive at least one dose of the vaccine were more likely to have received at least one dose of the vaccine than all of the other ethnic groups combined.

Sustaining the successes of vaccination in protecting public health

This issue of Eurosurveillance celebrates the important public health advances achieved thanks to vaccination, and emphasises the importance of maintaining these achievements, as highlighted by the editorial written by the Chief Scientist of the European Centre for Disease Prevention and Control, Piotr Kramarz, and Eurosurveillance ‘s Editor-in-Chief Ines Steffens, which also noted there had been a 10-fold increase in measles cases from 2023 to 2024. [3]

The issue also includes the following articles on immunisation and vaccines:

• A study on immunity against measles in the Austrian population found that almost all people born before 1970 were immune to the virus, likely due to childhood infection, while many people born after 1990 either were not immune or had insufficient immunity against the virus, as virus circulation had decreased and most immunity had been acquired due to vaccination. [4]
• A study that tested children in London for poliovirus after the virus had been detected in sewage with leftover stool samples from paediatric appointments, a convenient method to screen for polio in humans after detection in the environment [5]

An investigation into a meningococcal disease outbreak in an English elderly care home showed that the 4CMenB vaccine reduced the risk of adverse effects from the disease among the residents. [6]

[1] Scronias Dimitri, Fressard Lisa, Fonteneau Laure, Guagliardo Valérie, Verger Pierre. Persistence of major socio-economic inequalities in childhood measles–mumps–rubella vaccination coverage and timeliness under vaccination mandates, France, 2015 to 2024. Euro Surveill. 2025;30(16):pii=2400674. https://doi.org/10.2807/1560-7917.ES.2025.30.16.2400674

[2] Jary Hannah, Pullen Adam, Howett David, Hani Erjola, Suleman Shakeel, Byrne Lisa, Booth Emma, Puleston Richard, Saliba Vanessa, Campbell Colin NJ, Chatt Carol. Sociodemographic inequalities in the epidemiology and vaccine uptake within a large outbreak of measles in Birmingham, England, 2023 to 2024. Euro Surveill. 2025;30(16):pii=2400652. https://doi.org/10.2807/1560-7917.ES.2025.30.16.2400652

[3] Kramarz Piotr, Steffens Ines. Sustaining successes and addressing challenges to vaccination – a continued public health mission. Euro Surveill. 2025;30(16):pii=2500284. https://doi.org/10.2807/1560-7917.ES.2025.30.16.2500284

[4] Springer David N, Borsodi Christian, V Camp Jeremy, Redlberger-Fritz Monika, Holzmann Heidemarie, Kundi Michael, Aberle Judith H, Stiasny Karin, Weseslindtner Lukas. Seroprevalence against measles, Austria, stratified by birth years 1922 to 2024. Euro Surveill. 2025;30(16):pii=2400684. https://doi.org/10.2807/1560-7917.ES.2025.30.16.2400684

[5] Rowland Thomas, Gopal Robin, Patel Monika, Celma Cristina, Campbell Colin NJ, Machin Nicholas, Taylor Scott, Graham Shauni-lea, Harris Kathryn, Pereira Spiro, Saliba Vanessa, Zambon Maria. Community surveillance after detection of poliovirus in the environment in London, United Kingdom, October 2022 to April 2023. Euro Surveill. 2025;30(16):pii=2500025. https://doi.org/10.2807/1560-7917.ES.2025.30.16.2500025

[6] Heymer Emma J, Clark Stephen A, Campbell Helen, Ribeiro Sonia, Walsh Lloyd, Lucidarme Jay, Bai Xilian, Irving Tom, Hoad Anna, Morgan Jaime, Borrow Ray, Ladhani Shamez N. Use of 4CMenB vaccine in the control of an outbreak of serogroup B invasive meningococcal disease in an elderly care home, England, November 2023. Euro Surveill. 2025;30(16):pii=2400673. https://doi.org/10.2807/1560-7917.ES.2025.30.16.2400673