Hantavirus Outbreak on Cruise Ship: What You Need to Know

An outbreak of hantavirus, a rare rodent-borne virus, has been reported on a Dutch-flagged cruise ship, affecting eight passengers and leading to three fatalities. As the MV Hondius prepares to dock in the Canary Islands, health authorities are finalizing plans for the safe disembarkation of remaining passengers and crew, while emphasizing that the situation, though serious, is not expected to escalate into a pandemic similar to COVID-19. Hantaviruses are a group of viruses typically carried by rodents and can be transmitted to humans through exposure to their droppings, urine, or saliva. While not causing illness in rodents, they can be severely debilitating or fatal in humans. The specific type of hantavirus determines symptoms; varieties in the Americas, for instance, can cause hantavirus cardiopulmonary syndrome (HPS), which affects the lungs and heart with a fatality rate of up to 50%. The current outbreak saw a man develop respiratory symptoms on April 6, dying five days later. His wife also succumbed to the virus on April 26, after leaving the ship. A third passenger died on May 2, and four others were evacuated for treatment. An eighth person, who disembarked in Saint Helena, was later confirmed to have contracted the Andes virus, a form of hantavirus unique for its human-to-human transmission capability. Despite the alarming fatalities, health experts, including officials from the World Health Organization (WHO), stress that this outbreak is fundamentally different from the early stages of the COVID-19 pandemic. The Andes virus is a known pathogen, and diagnostic kits are readily available, with Argentina sharing its established resources. Crucially, the virus requires close, prolonged contact—such as with a partner, household member, or medical caregiver—for human-to-human spread, unlike the highly transmissible airborne nature of SARS-CoV-2. To contain the spread, all remaining passengers on the MV Hondius have been asked to stay in their cabins, which are undergoing disinfection. Doctors and health professionals from the WHO and the European Center for Disease Prevention and Control (ECDC) have boarded the ship to assess everyone. While no new symptoms have emerged among those still on board, the Andes virus has a long incubation period, up to six weeks, necessitating continued vigilance. Passengers are advised to wear medical masks when outside their rooms, and WHO Director-General Tedros Adhanom Ghebreyesus reported improved morale on board as the ship nears its destination. Previous outbreaks of the Andes virus, such as one in Argentina between November 2018 and February 2019 that resulted in 34 confirmed cases and 11 deaths, demonstrate its limited spread even when triggered by social gatherings. This historical data provides some reassurance that with robust public health measures and international cooperation, the current outbreak can be contained. Unfortunately, there are no specific antiviral treatments or vaccines for hantavirus; early intensive care is the primary recommendation to save lives. Investigations are ongoing to pinpoint the origin of the infection. The deceased couple had traveled through Argentina, Chile, and Uruguay on a birdwatching trip prior to boarding the ship, visiting areas known to harbor rat species carrying the Andes virus. The WHO is collaborating with Argentine authorities to retrace their movements. Furthermore, several US states are monitoring their nationals who disembarked from the ship, and the WHO continues to share technical information with the US Centers for Disease Control and Prevention, ensuring a coordinated global response to potential suspect cases linked to the vessel.