What is the Andes virus? The hantavirus linked to a cruise ship outbreak is the most deadly strain

The Andes strain of hantavirus, responsible for three deaths and five illnesses aboard the luxury cruise ship MV Hondius, has raised global health concerns. The ship departed from Argentina, where the virus is endemic, and cases have since been confirmed in South Africa. Three fatalities—two Dutch nationals and another woman—have been reported, with one patient in intensive care. The Andes strain is the most severe form of hantavirus and the only known variant capable of spreading person-to-person, primarily through respiratory droplets or bodily fluids. Unlike other strains, it does not require direct contact with rodents like rats or mice, though those remain the primary carriers. Experts warn that while human-to-human transmission is rare—accounting for just 2% to 5% of cases—it can occur in close-contact settings, such as healthcare environments or intimate interactions. The incubation period for the virus ranges from nine to 40 days, meaning potential cases from the cruise ship may emerge within the next week. A 2018 outbreak in Epuyén, Argentina, demonstrated superspreading potential, with three infected individuals triggering 34 cases and 11 deaths after attending crowded social events. Public health officials, including the World Health Organization, stress that the outbreak does not pose the same risk as COVID-19 or influenza. The virus spreads differently and is not airborne in the same way, though early-stage infections are most contagious. Most documented human transmission involves close contact or healthcare exposure without proper protection. Investigations are ongoing, but experts insist the risk to the broader public remains low. The Andes strain’s severity underscores the need for vigilance, particularly in regions where rodent populations carry the virus. Travelers and healthcare workers are advised to remain cautious, especially in South America, where the strain is most prevalent.