A dangerous rodent-borne virus has claimed three lives aboard a cruise ship in the Atlantic Ocean, with one confirmed case reported.
Hantavirus Transmission
Hantaviruses are primarily carried by rodents, including mice, rats, and voles, which themselves show no symptoms of the disease. Human infection typically occurs through inhalation of airborne particles from rodent droppings, urine, or saliva.
The pathogen can also enter the body through skin wounds. Mouse urine is particularly dangerous, remaining infectious for several months, while other secretions remain infectious for weeks.
Cruise Ship Incident and Polish Nationals
The World Health Organization (WHO) reported on Sunday the deaths of three passengers on a cruise ship traveling in the Atlantic Ocean, with one confirmed hantavirus infection. On Monday, a spokesperson for the Ministry of Foreign Affairs, Maciej Wawiór, stated that all Polish citizens on board the ship are in good health.
Understanding Hantaviruses
Hantaviruses are RNA viruses belonging to the Bunyaviridae family. The virus remains infectious for longer periods in colder temperatures, leading to a higher incidence of cases in regions like Russia.
Those at increased risk include forestry workers, farmers, hunters, soldiers, construction workers, tourists, and anyone frequently near rodent habitats, including golfers.
Severity and Symptoms of Infection
The severity of hantavirus infection varies, ranging from mild to life-threatening. It can lead to Hemorrhagic Fever with Renal Syndrome (HFRS) or, more severely, Hantavirus Pulmonary Syndrome (HPS), which has a mortality rate of up to 50 percent. Human-to-human transmission is rare.
Historical Context: The Hantaan Virus
The first isolated hantavirus was the Hantaan virus, discovered in 1976 and causing Korean hemorrhagic fever with renal syndrome. The name originates from the Han River in South Korea.
During the Korean War (mid-1950s), the then-unknown Hantaan virus infected 2500 American soldiers, killing 5 to 10 percent of them, raising initial fears of biological warfare.
Global Distribution of Hantaviruses
Over time, numerous hantavirus strains have been identified worldwide. In the Americas, examples include Sin Nombre, Andes, Oran, Lechiguanas, and Hu39694. Betsy Arakawa, wife of actor Gene Hackman, died from a hantavirus infection in 2025, and Hackman, suffering from Alzheimer’s, died shortly after.
Hantavirus in Poland and Europe
In Europe, infections are mainly caused by the Dobrava virus (DoBV), found in forest mice, and the Puumala virus (PUUV), present in voles. Polish studies have shown antibodies against these viruses in a small percentage of forestry workers, with infections often asymptomatic or mild.
Several to dozens of cases are reported annually in Poland, primarily in the Subcarpathian region, typically resulting in HFRS.
Treatment and Prevention
Treatment for hantavirus infection is primarily supportive, as there are no specific antiviral medications. Symptoms appear one to eight weeks after exposure, according to the U.S. Centers for Disease Control (CDC).
Early treatment is crucial, as the infection can progress rapidly and become life-threatening. Supportive care includes rest, hydration, oxygen therapy, and dialysis if kidney problems develop.
Initial symptoms, such as fatigue and muscle aches, are non-specific and resemble the flu. As the disease progresses, symptoms may include cough, shortness of breath, and chest tightness due to fluid buildup in the lungs, or kidney problems. Approximately one-third of patients with respiratory symptoms may die.
The best prevention method is minimizing contact with rodents and their droppings. Protective gloves and bleach solutions should be used when cleaning rodent droppings. Sweeping and vacuuming can aerosolize the virus. Rodent populations should be controlled in inhabited areas.