Hantavirus outbreak linked to cruise ship travel, Multi-locations
This is the fourth Disease Outbreak News report on the Andes hantavirus outbreak linked to cruise ship travel, following the notification to the World Health Organization (WHO) on 2 May 2026 of severe respiratory illness cases aboard M/V Hondius, a cruise ship. Since the last DON was published on 13 May, three additional confirmed cases were reported, from Canada, the Netherlands, and Spain. The previously reported inconclusive case from the United States of America was subsequently determined to be negative following further laboratory testing and has been removed from the total case count. All cases to date have been passengers or crew members on the ship. As of 27 May, a total of 13 cases, including three deaths, have been reported (case fatality ratio 23%). Eleven cases have been laboratory-confirmed for Andes virus (ANDV) infection, and two are probable cases. Given the long incubation period of up to six weeks, it is not unexpected that cases continue to be reported until the end of the six weeks since last exposure. Through the International Health Regulations (2005) (IHR) channels, National IHR Focal Points (NFPs) have all been informed and are supporting international contact tracing and monitoring efforts. WHO has assessed the risk posed by this event to the global population as low and will continue to monitor the epidemiological situation and update the risk assessment as needed.