The centre warned that “uneven” implementation of services and “outdated” national strategies had contributed to the rise.
A Missing Factor
However, one area overlooked or avoided by much of the reporting and by the ECDC’s reports is migration. The ECDC does not provide a broad breakdown of bacterial STI cases by region of origin, instead referring in some reports to wider categories such as “social vulnerability”.
That makes it harder to assess the role of migration status, even though national statistics and regional studies suggest that migrant status can be significantly associated with bacterial STI diagnosis. One study also said that ensuring access to sexual health services for vulnerable populations such as migrants is “essential” to addressing the global rise in STIs.
The category of social vulnerability does provide some hints as to the role migration plays in Europe’s surge in STIs, noting for instance that the rise in congenital syphilis has been largely associated with “maternal social vulnerability”, as well as inadequate antenatal care.
National Reports Fill in the Gaps
National reports offer valuable insight into this issue, as the ECDC’s report on congenital syphilis highlights.
It shows that six countries reported data on a mother’s country of birth for a total of 63 congenital syphilis cases. Of these, 17 were born outside the reporting country, making up just over a quarter (27%) of the cases. Some 80% of Spain’s 2024 reported congenital syphilis cases were to foreign-born mothers, while in Portugal, the figure was 53%.
Spain and Portugal have the highest rates of congenital syphilis cases among European nations, the ECDC report shows.
Although congenital syphilis remains rare in Europe, confirmed cases rose sharply from 78 in 2023 to 140 in 2024, the most recent year for which data is available.
While these statistics examine just one type of STI, a 2025 study on the incidence of such diseases among Spain’s young adult population highlighted the overrepresentation of people from a migrant background among those diagnosed.
While 11.6% of Spain’s young adult population are immigrants, adolescents born in Latin America alone made up 28% of the study’s sample, which examined cases among adolescents aged between 10 and 19 years. This aligns with data from adult populations, the study notes, indicating a “specific vulnerable group”.
Migrant Status a Significant Factor
Another 2025 study from France on the prevalence of bacterial STIs among migrant populations examined medical records from patients attending a Paris-based clinic between 2019 and 2023. The study, indexed by the US National Library of Medicine, found that migrant status was “significantly” associated with bacterial STI diagnosis.
It recommended that the care of migrants should include “systematic screening” for bacterial STIs, adding that ensuring access to sexual health services for vulnerable populations is “essential” to addressing a global rise in STIs.
While the recent release from the ECDC focuses on bacterial STIs, national studies on the transmission of viral STIs such as HIV have highlighted the prevalence of such infections in migrant populations.
In Ireland, where the rate of HIV diagnoses was the second highest in the EU per capita in 2024, some 74% of first-time diagnoses were among people from outside Ireland.
Among those born outside Ireland, the country where the infection was acquired was listed as Ireland for 30%, outside Ireland for 39% and unknown for 31%.
Ireland’s HIV diagnosis rate rose from 7.4 cases per 100,000 people in 2012 to 19.2 in 2024, after a brief dip during the Covid-19 period.
Given the growing body of national research linking migration status to higher STI diagnosis rates, migration should be part of any serious public health analysis of the surge. If Europe is to respond effectively, the evidence must inform both disease prevention policy and the wider debate.