An illness linked to rodents has been identified as the likely culprit behind a recent cruise ship outbreak, which resulted in the deaths of three individuals and left several others unwell.
Research reveals that hantaviruses have existed for centuries, with recorded outbreaks in both Asia and Europe. In these regions, the virus is connected to hemorrhagic fever and kidney problems. It wasn’t until the early 1990s that a new type of hantavirus was found in the southwestern United States, responsible for causing hantavirus pulmonary syndrome, an acute respiratory condition.
Public interest in this disease surged last year following the tragic death of Betsy Arakawa, the wife of late actor Gene Hackman, who succumbed to a hantavirus infection in New Mexico.
The World Health Organization announced on Sunday that they are conducting thorough investigations into the cruise ship outbreak, which includes detailed laboratory tests and epidemiological studies. Efforts to sequence the virus are also underway.
The virus is spread by rodents and more rarely, people
Hantavirus primarily spreads through contact with rodents or their bodily fluids, such as urine, saliva, or droppings. The risk increases when these materials are disturbed and become airborne, presenting an inhalation hazard. Exposure often occurs in residential areas, cabins, or sheds, especially during cleaning or when exploring spaces with mouse droppings.
According to WHO, although rare, there are instances where hantaviruses can be transmitted directly between humans.
The U.S. Centers 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 Center who for years has been studying the disease and helping patients.
Most U.S. cases are in Western states. New Mexico and Arizona are hot spots, Harkins said, likely because the odds are greater for mouse-human encounters in rural areas.
The illness starts with flu-like symptoms
An infection can rapidly progress and become life-threatening. Experts say it can start with symptoms that include a fever, chills, muscle aches and maybe a headache.
“Early in the illness, you really may not be able to tell the difference between hantavirus and having the flu,” said Dr. Sonja Bartolome of UT Southwestern Medical Center in Dallas.
Symptoms of hantavirus pulmonary syndrome usually show between one to eight weeks after contact with an infected rodent. As the infection progresses, patients might experience tightness in the chest, as the lungs fill with fluid.
The other syndrome caused by hantavirus – hemorrhagic fever with renal syndrome – usually develops within a week or two after exposure.
Death rates vary by which hantavirus causes the illness. Hantavirus pulmonary syndrome is fatal in about 35% of people infected, while the death rate for hemorrhagic fever with renal syndrome varies from 1% to 15% of patients, according to the CDC.
A lot of unknowns about the illness and treatment
There is no specific treatment or cure, but early medical attention can increase the chance of survival.
Despite years of research, Harkins said many questions have yet to be answered, including why it can be mild for some people and very severe for others and how antibodies are developed. She and other researchers have been following patients over long periods of time in hopes of finding a treatment.
There are “a lot of mysteries,” she said, noting that what researchers do know is that rodent exposure is key.
The best way to avoid the germ is to minimize contact with rodents and their droppings. Use protective gloves and a bleach solution for cleaning up rodent droppings. Public health experts caution against sweeping or vacuuming which can cause virus particles to get into the air.
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