A dramatic spike in measles cases across Europe in 2024, driven by low vaccination rates and widening immunity gaps, has reignited urgent calls for catch-up immunization and strengthened disease surveillance. Country reports from Austria, Belgium, Bulgaria, Croatia, Cyprus, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden. Did you know that unvaccinated individuals have a 90% chance of being infected with the measles virus when exposed to it? In 2024, measles cases surged across Europe, reaching the highest levels seen in decades. A recent report by the European Centre for Disease Prevention and Control (ECDC) discussed this alarming rise in measles cases, the factors contributing to outbreaks, and the urgent strategies needed to prevent future epidemics. Measles Seasonal Resurgence: After three years of disrupted patterns, measles cases in 2024 followed a classic seasonal curve, peaking in spring and early summer, a pattern not seen since before the COVID-19 pandemic. Measles is among the most contagious infectious diseases, spreading easily through airborne respiratory droplets. A single infected person can transmit the virus to between 12 and 18 others. Vaccination efforts since the 1960s have greatly reduced measles worldwide, but the measles virus continues to cause significant illness and death, particularly in young children. Global estimates suggest that measles still causes close to 140,000 deaths among children each year. Although immunization coverage is generally high across Europe, localized gaps persist, making some populations vulnerable to outbreaks. Studies suggest that achieving and maintaining at least 95% vaccination coverage with two doses is critical to prevent the spread of measles. However, vaccination coverage has fluctuated, especially during the coronavirus disease 2019 (COVID-19) pandemic, when healthcare disruptions and, in some countries, vaccine hesitancy created immunity gaps. Furthermore, the influx of cases from countries where measles remains endemic continues to pose a threat to disease control efforts in Europe. The report specifically highlights that Romania experienced a sharp decline in first and second dose coverage between 2022 and 2023, whereas Austria showed improvement in second dose coverage. The current report The 2024 Annual Epidemiological Report on measles is based on data retrieved from the EpiPulse Cases system on March 20, 2025. EpiPulse offers enhanced data collection and analysis of communicable disease cases, surpassing the capabilities of the older European Surveillance System. The report utilized cases reported by 30 European Union (EU) and European Economic Area (EEA) countries. Romania’s immunization crisis: First-dose vaccination coverage plummeted by nearly 10% between 2020 and 2023, leaving toddlers in Europe’s hardest-hit nation unprotected. The surveillance relied mainly on comprehensive, passive reporting systems covering national populations, and data submission follows standard EU case definitions, adopted between 2008 and 2018. Vaccination coverage estimates were sourced from the World Health Organization’s (WHO) Global Health Observatory datasets and immunization coverage estimates developed by the WHO and United Nations Children’s Fund (UNICEF). The report also used ECDC's Surveillance Atlas of Infectious Diseases and monthly reports on measles and rubella cases. Data on cases, vaccination status, outcomes, hospitalizations, and complications were collected and analyzed to identify trends, seasonality, age group distribution, vaccination gaps, and importation status. Age-specific attack and vaccination rates were calculated, and case importations were classified based on travel history and exposure outside reporting countries. The hospitalization and complication data were used to assess the severity of cases, and outcome status, including death, was recorded whenever available. Additionally, historical trends in measles vaccination coverage, notification rates, and cross-country comparisons were incorporated to identify emerging vulnerabilities and inform recommendations for public health action. The report also notes that eleven EU/EEA countries have implemented mandatory measles vaccination policies, which may contribute to differences in coverage and age-specific vulnerability. Key findings The report indicated that measles cases had risen dramatically in 2024 across the EU/EEA, with over 35,000 cases reported, nearly ten times higher than the number of cases in 2023. Romania alone accounted for 87% of all cases. Moreover, the notification rates surpassed pre-pandemic levels, reaching 77.4 cases for every million individuals. Infants under one year were the most affected group, with an infection rate of 1,175.4 per million, followed closely by children between the ages of 1 and 4 years. Approximately 87% of reported cases involved individuals who were not vaccinated. More alarming was the finding that 90% of children aged one to four were unvaccinated, revealing significant immunity gaps in a critical age group. The report also highlighted that immunity gaps exist among older children and adults, with several countries reporting that the majority of cases occur in people over 30 years old. This suggests a history of under-vaccination in these populations. For example, in France, Italy, Spain, and Poland, the majority of measles cases in 2024 occurred in adults aged 30 and above, while in Romania, most cases were in young children. Hospital hotspots: Among the 24,529 hospitalized cases, 82% were unvaccinated, including 739 fully vaccinated individuals, highlighting the rare but real occurrence of breakthrough infections. Hospitalization rates were also high, with 79% of cases requiring hospital care, predominantly among the unvaccinated children. In fact, approximately 82% of hospitalised cases were unvaccinated, and about 80% of those who developed complications such as pneumonia or encephalitis were also unvaccinated, further underscoring the risks faced by those without protection. Furthermore, complications such as pneumonia and encephalitis were frequently reported. Deaths from measles were also seen to increase sharply, with 23 mortalities — 22 in Romania alone — compared to just three in 2023. Infants and young children represented most of these deaths. Additionally, the number of imported cases had also increased, particularly from within Europe, highlighting ongoing risks of cross-border transmission. Despite the existence of longstanding vaccination programs, coverage for the first dose declined slightly to 93.9%, and for the second dose to 88.8%. Only four countries met the target of greater than 95% coverage for the second dose of measles immunization in 2024. The report further notes that only three countries achieved greater than 95% coverage for both the first and second doses in 2023. The gaps were more evident among older children and adults, suggesting a history of under-vaccination. The researchers noted that the information on vaccination status for some age groups was incomplete, and mild cases might not have been reported, which may have underestimated the true incidence. Conclusions In summary, the 2024 epidemiological report by the ECDC revealed a troubling resurgence of measles in Europe, highlighting the severe consequences of immunity gaps and suboptimal vaccination coverage. With infants and young children most affected, urgent actions are needed to rebuild community protection through vaccination campaigns, targeted outreach, and strengthened surveillance to prevent further measles resurgence. Strengthening digitalised immunisation information systems and international collaboration to prevent cross-border transmission are also emphasized as key strategies in the report. The report also emphasizes the importance of targeted catch-up campaigns for cohorts that have been missed, particularly among adolescents and adults. It highlights how national differences in MMR policies—such as timing of vaccine doses and catch-up programmes—may partly explain differences in age-specific vulnerability across the region.