Nine cases of hantavirus linked to the MV Hondius cruise ship have been confirmed by the World Health Organization, which warned more infections could emerge as the virus can incubate for up to six weeks.
Hantaviruses are viruses that naturally infect rodents, first discovered in 1976 near the Hantan River in South Korea. Depending on the variant, infection can lead to Hantavirus Cardiopulmonary Syndrome, affecting the lungs and heart, or Hemorrhagic Fever with Renal Syndrome, affecting the kidneys.
The Andes strain is the only known variant that can cause limited human-to-human transmission through close, prolonged contact. Transmission occurs through contact with contaminated rodent urine, droppings, or saliva. Human-to-human transmission is rare and has been documented among household members or intimate partners.
The WHO and the European Centre for Disease Prevention and Control consider the risk to the general population very low. Passengers and crew with symptoms require immediate medical isolation; those without symptoms must quarantine for up to six weeks. Recent genetic sequencing confirms the infections share a single source, and it is not a new variant.
There is no specific treatment or cure. The case fatality rate ranges from less than 1 percent in Asia and Europe to up to 50 percent in the Americas. Symptoms typically appear one to eight weeks after exposure and include fever, headache, muscle aches, and gastrointestinal issues.
Hantavirus infections are uncommon in Europe, with 1,885 cases registered in 2023. One notable outbreak occurred in Argentina in 2018-2019, with 34 confirmed infections and 11 deaths.