A concerning trend is emerging across Europe as measles cases rise, exacerbated by a highly contagious variant originating from morocco. Health officials are on high alert, especially in Belgium, where wastewater analysis reveals a significant presence of the B3 variant.

The Moroccan Measles Outbreak: A Transnational Threat

Since September 2023, Morocco has been grappling with a ample measles outbreak. Over 40,000 suspected cases have been reported, with approximately 6,300 confirmed and nearly 150 fatalities, primarily affecting children under 12. The virus has spread rapidly in densely populated environments such as schools and prisons.

The severity of the situation prompted European health agencies to issue travel advisories,emphasizing the importance of vaccination for individuals planning trips to Morocco. Faced with the epidemic of measles which is currently raging in morocco, Public health France recalls the importance of vaccination in the event of a project of stay and calls for the vigilance of health professionals in the context of school holidays, as stated by Public Health France, highlighting the need for proactive measures.

The impact of the outbreak has extended beyond Morocco’s borders,with several European nations reporting cases linked to travel to the affected region. The netherlands has identified 45 recent cases directly connected to stays in morocco. Spain reported 107 cases in 2025, with 34% attributed to infections imported from Morocco and Romania. Belgium has been particularly hard-hit, with 551 cases recorded between February 2024 and January 2025, according to the European Center for Disease prevention and Control (ECDC), placing it among the most affected european countries, trailing only Romania, Italy, and Germany.

France Grapples with Resurgence of Measles Cases

The ripple effects of the Moroccan epidemic are particularly evident in the Provence-Alpes-Côte d’Azur region of France. the Regional Health Agency (ARS) has reported a notable surge in cases linked to the outbreak.Since January 2025, the region has recorded 21 cases, accounting for a third of the national total, with nearly 30% of infected individuals experiencing serious complications.

A localized outbreak was identified at the Thiers high school in Marseille, with five confirmed cases in February. The ARS emphasizes the critical role of vaccination, mandatory in France since 2018, in curbing the spread of the virus.

Belgium’s Wastewater reveals troubling viral Load

Researchers at the Catholic University of Louvain in Belgium have detected significant quantities of the B3 variant,originating from Morocco,in Brussels’ wastewater. While the Belgian health institute Vivalis has only identified 18 cases this year, experts believe this figure might potentially be an underestimation due to the variant’s high viral load, which can complicate detection in some patients.

This concerning progress has prompted Belgian health authorities to intensify epidemiological surveillance and actively promote vaccination efforts.

The COVID-19 Pandemic’s Lingering Impact on Vaccination Rates

The overall resurgence of measles in Europe is partly attributed to a decline in vaccination coverage during the COVID-19 pandemic. Lockdowns and the redirection of healthcare resources led to delays in routine childhood vaccination schedules, creating pockets of vulnerable populations. According to a recent WHO report, measles vaccination rates in Europe have fallen below the 95% threshold needed for herd immunity in several countries.

For example, in 2024, the UK Health Security Agency (UKHSA) declared a national incident due to rising measles cases, directly linking the increase to lower vaccination rates during the pandemic. This underscores the critical need to catch up on missed vaccinations to protect communities from preventable diseases.

Call for Action: Strengthening International Cooperation

In response to this escalating health threat, European and Moroccan health authorities are intensifying vaccination campaigns and advocating for enhanced international collaboration to avert a more severe health crisis. Experts also advise increased vigilance for travelers to and from Morocco and other high-risk areas, emphasizing the importance of verifying vaccination status.

“Vaccination remains the most effective tool in preventing measles outbreaks. We urge all individuals, especially those planning to travel, to ensure they are fully vaccinated,”
Dr. Isabella Rossi, ECDC Senior epidemiologist