A rodent-borne illness is suspected of causing an outbreak aboard a cruise ship that has killed three people and sickened others.

Studies indicate hantaviruses have been around for centuries, with outbreaks documented in Asia and Europe.

In the Eastern Hemisphere, it has been linked with haemorrhagic fever and kidney failure. It wasn’t until the early 1990s that a previously unknown group of hantaviruses emerged in the southwestern United States as the cause of an acute respiratory disease now known hantavirus pulmonary syndrome.

The disease gained attention last year after late actor Gene Hackman’s wife, Betsy Arakawa, died from a hantavirus infection in New Mexico.

The World Health Organization said in a statement on Sunday that detailed investigations of the cruise ship outbreak are ongoing, including further laboratory testing and epidemiological investigations. Sequencing of the virus also is ongoing.

Hantavirus is mainly spread by contact with rodents or their urine, saliva or droppings, particularly when the material is disturbed and becomes airborne, posing risk of inhalation.

People are typically exposed to hantavirus around their homes, cabins or sheds, especially when cleaning out enclosed spaces with little ventilation or exploring areas where there are mouse droppings.

WHO says that while it rarely happens, hantaviruses can also spread directly between people.

The US Centres for Disease Control and Prevention began tracking the virus after a 1993 outbreak in the Four Corners region – the area where Arizona, Colorado, New Mexico and Utah meet.

It was an astute physician with the Indian Health Service who first noticed a pattern of deaths among young patients, said Michelle Harkins, a pulmonologist with the University of New Mexico Health Sciences Centre who for years has been studying the disease and helping patients.

Most US cases are in Western states. New Mexico and Arizona are hotspots, Harkins said, likely because the odds are greater for mouse-human encounters in rural areas.

• An AP report