There has been a great deal of news coverage recently about the hantavirus outbreak aboard the cruise ship MV Hondius, where several passengers became seriously ill and three people reportedly died. Health officials around the world are now monitoring passengers who may have been exposed. 

But what exactly is hantavirus?

Hantavirus is not a new disease. It has been recognized for decades and is primarily carried by rodents, especially certain species of mice and rats. In the United States, the deer mouse is the most common carrier. The virus first gained widespread public attention in 1993 after a deadly outbreak in the Four Corners region of the Southwest, where Arizona, New Mexico, Colorado, and Utah meet.

People usually become infected by breathing in microscopic particles contaminated with rodent urine, droppings, or saliva. Sweeping out an old shed, garage, attic, barn, or cabin where infected rodents have been living can stir virus particles into the air. Less commonly, infection may occur through rodent bites or contaminated food.

One important fact is that hantavirus is generally not considered highly communicable from person to person. Most cases occur from direct exposure to infected rodents or their waste. However, health officials investigating the recent cruise ship outbreak believe the rare “Andes strain” of hantavirus may have been involved. This particular strain, found mainly in South America, has shown limited human-to-human transmission in rare situations. 

The illness often begins like the flu. Early symptoms may include:

• Fever
  • Chills
  • Muscle aches
  • Headache
  
  • Fatigue
  • Nausea and vomiting

After several days, some patients develop coughing and severe shortness of breath as the lungs begin filling with fluid. This dangerous condition is called Hantavirus Pulmonary Syndrome (HPS), which can rapidly become life-threatening.

There is no specific cure or antiviral treatment for hantavirus. Medical care mainly focuses on supportive treatment, including oxygen therapy and intensive care when necessary. Early diagnosis and rapid medical attention can improve survival.

Fortunately, hantavirus infections remain rare in the United States. The Centers for Disease Control and Prevention report only a small number of cases each year. Still, because the disease can be severe, prevention is extremely important.

Health experts recommend:

• Sealing holes where rodents can enter homes
•  Storing food securely
• Using gloves and disinfectants when cleaning rodent-infested areas
• Avoiding sweeping or vacuuming rodent droppings directly, which can send particles into the air

The recent cruise ship incident has reminded the public that infectious diseases can still emerge unexpectedly, even in modern settings. Experts stress that the overall risk to the general public remains low, and this outbreak is not considered another COVID-type situation. 

Although hantavirus is generally not considered contagious from person to person, health officials investigating the recent cruise ship outbreak believe the rare “Andes strain” may have been involved. Unlike the strains usually seen in the United States, the Andes strain of hantavirus, found mainly in South America, has shown limited human-to-human transmission in a small number of documented cases. Investigators also believe some passengers may have been exposed to a common environmental source, such as areas contaminated by rodent droppings or urine aboard the ship or during shore excursions. Experts stress that this type of transmission is very uncommon, and for most hantavirus infections, people become ill only after direct exposure to infected rodents or contaminated dust in the environment.

Michael Kossove is professor emeritus and an adjunct professor of microbiology at Touro University’s School of Health Sciences. He is a polio researcher and the author of “Polio Post-Polio and the Survivors.” He can be reached at Professormike2@aol.com.