90-Second Read: Public health in action: from detection to response – how International Health Regulations (2005) guided response to Hantavirus outbreak

The complexities of the Hantavirus cluster detected on a cruise ship demonstrate why the IHR are the backbone of international outbreak coordination and response, underlining the importance of global cooperation and solidarity in tackling health threats that know no borders. Contact tracing During travel-related outbreaks, WHO and countries support international contact tracing through IHR coordination, linking clinical detection to public health follow-up across borders. During the Hantavirus response, the IHR NFP for the Netherlands and the conveyance operator informed 12 countries whose nationals had disembarked earlier at Saint Helena, as well as the public through the WHO Disease Outbreak News portal. In a world where people can cross borders in minutes, an infectious disease event, such as the cluster of Hantavirus cases on the MV Hondius cruise ship, can quickly become a multi-country challenge.

24/7 surveillance, detection and notification From the moment that WHO is notified of a public health threat, IHR National Focal Points (IHR NFPs) and WHO engage in rapid, structured cross-border information exchange. This analysis, published on 10 May, turns multi-country laboratory data into actionable public health intelligence to guide quarantine protocols, medical evacuations and international contact tracing. Collective action gave us the response." "While this is a serious incident, WHO assesses the public health risk as low. Within days, cases of Hantavirus (Andes strain) had been confirmed in the Netherlands, South Africa and Switzerland.

Preparedness Under the IHR, countries are legally obligated to designate points of entry, including international airports and ports, and to develop, strengthen and maintain specific core public health capacities to prevent, detect and respond to health threats. This selection is based on risk assessments, traffic volume, and the need to manage the health risks associated with international travel and trade. In 2025 alone, the regional WHO team screened 224 000 pieces of information from both official sources, including the IHR, and media articles, resulting in 116 major public health events identified, of which 70 required immediate WHO operational response and follow-up. During acute public health events, Member States need timely, practical, evidence-based guidance.

Meanwhile WHO initiated outbreak investigations and developed guidance documents for the disembarkation and onward management of passengers, and the management of contacts ahead of their arrival in Tenerife, Spain. All passengers have since returned home and are under 42-day monitoring, according to WHO recommendations. Disembarkation in Tenerife When a port is not equipped to apply necessary health measures, a ship may be directed to proceed to the nearest suitable port if needed.