| Verified against primary record | |
| EU definition | Fewer than 5 cases per 10,000 people[1] |
|---|---|
| EU network | 24 European Reference Networks, 1,606 centres in 375 hospitals, October 2025[2] |
| What moves | Expertise, not the patient; patients do not access the networks directly[2] |
| Records read | Directive text, Commission pages and monitoring report, 30 September 2026 |
| Independently reported | |
| Prevalence estimate | 3.5 to 5.9 per cent of the world population, 2020 study[3] |
| Bands apply only to the rows beneath them. No figure counts rare disease patients travelling abroad, because no such figure is collected. No provider-supplied figures are used. | |
Medical travel for rare diseases describes journeys undertaken to reach specialist knowledge of a condition that too few clinicians have seen to diagnose or treat confidently close to home. The European Union defines a disease as rare when it affects fewer than 5 people per 10,000, a threshold set by Decision No 1295/1999/EC.[1]
The subject is unusual among medical travel topics in that the principal institutional response to it has been designed to make the travel unnecessary.
Moving expertise instead of patients
Article 12 of Directive 2011/24/EU requires the Commission to support the development of European Reference Networks between healthcare providers and centres of expertise. Among the objectives such a network must pursue, the Directive names facilitating the mobility of expertise, in its own words, virtually or physically.[4] The drafting places expertise, rather than the patient, as the thing that moves.
As of October 2025 there were 24 such networks, comprising 1,606 specialised centres located in 375 hospitals across 27 member states and Norway.[2] The Commission states plainly that patients do not access the networks directly: a national healthcare provider, with the patient’s consent, shares the case with the relevant network to obtain advice.[2] The mechanism is the Clinical Patient Management System, an information platform in place since 2017, which the Commission describes as enabling faster diagnoses, more accurate treatment plans, better patient outcomes and reduced patients’ travel.[5] More than 4,500 rare and complex clinical cases have been discussed through it since launch, a cumulative total for which no end date is given.[5]
What is not counted
The Commission’s data collection on cross-border patient mobility records requests, authorisations, reimbursements and amounts. It contains no breakdown by disease or condition, and rare diseases are not mentioned in it.[6] The 2025 monitoring report on the networks likewise carries no figures on patients physically travelling abroad.[2] No published figure counts rare disease patients who travel for care, because the data field does not exist.
One number in the monitoring report is easily misread. It records 416,000 new patients referred to network healthcare providers in 2024, up from 161,000 in 2018.[2] These are referrals to hospitals that happen to be network members, the great majority of them domestic. The report gives no cross-border split, and the figure is not a measure of medical travel.
The prevalence figures and where they come from
The Commission’s own rare diseases page states that between 6,000 and 8,000 distinct rare diseases are estimated to exist, and that between 27 and 36 million people in the European Union live with one.[1] Neither estimate carries a reference year, and neither carries a citation. Only the 5-per-10,000 threshold on that page is sourced.
A 2020 analysis of the Orphanet database traced the underlying assumption. Its authors state that the often quoted claim that rare diseases affect 6 to 8 per cent of the population was first used in Europe in French research documents of 1992 and 1993, which became the basis of the 1999 European legislation on orphan products, and they cite a 2010 United States National Academy report finding that those estimates were not accompanied by analysis or substantive citation of sources. Their own calculation puts cumulative point prevalence at 3.5 to 5.9 per cent of the global population, or 263 to 446 million people at any given time.[3] The commonly repeated European total therefore rests on a thirty-year-old unreferenced figure, and the peer-reviewed replacement is materially lower at the top of its range.
Authorisation and rarity
Where a patient does travel within the European Union, Article 8 of the Directive permits a member state to require prior authorisation for care that involves at least one overnight hospital stay, or that requires the use of highly specialised and cost-intensive medical infrastructure or medical equipment.[4] The test is framed around infrastructure and equipment rather than clinical complexity. Rarity of a disease is not itself a ground for requiring authorisation.
See also
- Medical travel for unavailable treatments, the neighbouring case where the treatment rather than the expertise is missing
- Cross-border healthcare, the legal framework under which such travel is authorised
- Medical travel for children, where rare conditions are disproportionately represented
- Government-funded treatment abroad, the route by which most such journeys are paid for
References
- European Commission, Directorate-General for Health and Food Safety. Rare diseases. Verified against primary record: institutional page opened and read. Retrieved 30 September 2026.
- European Commission, Directorate-General for Health and Food Safety. European Reference Networks: Monitoring report 2025, published 17 November 2025, and the European Reference Networks overview. Verified against primary record: report and page opened and read. Retrieved 30 September 2026.
- Nguengang Wakap S, Lambert DM, Olry A, et al. Estimating cumulative point prevalence of rare diseases: analysis of the Orphanet database. European Journal of Human Genetics, vol. 28, pp. 165 to 173, 2020. Independently reported: peer-reviewed study. Retrieved 30 September 2026.
- European Parliament and Council. Directive 2011/24/EU on the application of patients’ rights in cross-border healthcare. OJ L 88/45, 4 April 2011. Verified against primary record: Official Journal text read. Retrieved 30 September 2026.
- European Commission, Directorate-General for Health and Food Safety. Work of the ERNs. Verified against primary record: institutional page opened and read. Retrieved 30 September 2026.
- European Commission, Directorate-General for Health and Food Safety. Data on patient mobility under Directive 2011/24/EU, reference years 2018 to 2020, December 2021. Verified against primary record: official statistics publication opened and read. Retrieved 30 September 2026.
Sourcing note: the Directive text, the Commission pages and the 2025 monitoring report were opened and read on 30 September 2026. The prevalence analysis is independently reported. Two figures in circulation are avoided here. The count of 27 to 36 million affected Europeans is reproduced only alongside the analysis that traces it to unreferenced documents of 1992 and 1993. The count of 416,000 network referrals in 2024 is not a measure of cross-border travel and is presented as what it is. No source consulted counts rare disease patients travelling abroad, and that absence is stated rather than filled.