8 Hantavirus Questions, Answered

Here’s what older adults need to know about the virus amid an outbreak on a cruise ship

By Rachel Nania, AARP

 Updated May 11, 2026

Science Source

An outbreak of a rare virus on board a cruise ship that set sail from Argentina on April 1 has sparked concern and raised questions about hantavirus and the illness it can cause.  Here’s what we know about the ongoing situation, and what experts have to say about the risk to others.

1. What is hantavirus, and how does it spread?

Hantaviruses are a family of viruses carried by rodents, like rats and mice. The virus primarily spreads to people through contact with infected rodents or their waste. 

An example, says Dr. Michael Agnelli, associate program director for internal medicine at St. Joseph’s University Medical Center in Paterson, New Jersey, is if you come across rodent droppings in your house. “One of the first things people would do is probably grab a vacuum and try to vacuum it up,” he explains. But that’s not recommended. Vacuuming can kick contaminated particles into the air, and if the mouse is infected with hantavirus, those airborne particles could expose you to the virus, Agnelli says.

The virus can also spread through a bite or scratch from a rodent, though the Centers for Disease Control and Prevention (CDC) says this is rare. Person-to-person transmission is also rare, but it has been reported in past outbreaks with a specific strain of hantavirus, called the Andes virus, which is found in Latin America.

Even then, human-to-human spread is usually limited to people who have close contact with the sick person, like “household members, intimate partners and people providing medical care,” explained Dr. Tedros Adhanom Ghebreyesus, the World Health Organization’s (WHO) director-general, in a May 7 news conference.

2. What’s the current situation on the cruise ship?

There was an outbreak of hantavirus on a cruise ship carrying nearly 150 passengers in the Atlantic Ocean. So far, three people have died, and several are ill. WHO officials say the strain at the center of the outbreak is the Andes virus — the one known to spread from person to person.

On May 10, the ship docked at a port on Spain’s Canary Islands to offload the remaining guests. The ship’s operator says flights were waiting for passengers to transport them home.

Seventeen U.S. citizens who were on board the cruise ship were flown to Omaha and transported to the University of Nebraska Medical Center’s National Quarantine Unit for assessment and monitoring, since symptoms of the virus usually appear two to three weeks after infection; sometimes it can take as long as eight weeks, according to Harvard Health. 

One passenger from the U.S. has tested positive for the virus, but does not have symptoms, the medical center said in a news release.  

Thirty passengers — including six from the U.S. — deboarded the ship in late April in Saint Helena, health authorities said, and are also being closely monitored for signs of infection.

3. What symptoms does hantavirus cause — and are they worse in older adults?

Hantavirus can cause two types of disease that can be serious and deadly.

Hantaviruses found in the Western Hemisphere, including in the U.S., can cause hantavirus pulmonary syndrome, which affects the lungs, the CDC says. The Andes virus at the center of the current outbreak causes this type of disease. Early symptoms can include:

• Fatigue

• Fever

• Muscle aches

• Headaches

• Dizziness

• Chills

• Nausea, vomiting, diarrhea or abdominal pain

  
  

Four to 10 days after the first symptoms develop, the late symptoms appear, which can include:

• Coughing

• Shortness of breath

• Tightness in the chest

“In severe cases, the immune system essentially goes into overdrive, causing the lungs to fill with fluid even without widespread destruction of lung tissue,” Virginia Tech disease ecologist Luis Escobar explained in a statement.

Hantaviruses found mostly in Europe and Asia can cause what’s known as hemorrhagic fever with renal syndrome. Symptoms can include:

• Intense headaches

• Back and abdominal pain

• Fever/chills

• Nausea

• Blurred vision

• Low blood pressure

• Lack of blood flow

• Internal bleeding

• Acute kidney failure, which can cause severe fluid overload

  
  

There are no vaccines or specific medications available to prevent or treat illness caused by hantavirus. It’s fatal in about 4 out of 10 people who get it, the Cleveland Clinic says.

The available data suggest that older adults have hantavirus mortality rates similar to those of other age groups, says Kari Debbink, a teaching professor of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health. Those at highest risk tend to be people of working age, often due to occupational exposure to rodents through activities like agricultural and janitorial work, she explains. 

4. Will we see the number of infections rise?

It’s possible. This is largely due to the virus’s incubation period — the time between when a person is infected and when they start to show symptoms.

“These numbers may change as we’re doing follow-up. We may see some additional cases being reported, and that shows that the active follow-up is happening and that the testing is being done,” says Maria Van Kerkhove, an infectious disease epidemiologist with the WHO. 

5. What’s the difference between the way hantavirus spreads and COVID spreads?

Though this outbreak shares some eerie similarities to the early days of the COVID-19 pandemic, global health experts say this situation is much different.

For starters, it’s a very different virus from the coronavirus, Van Kerkhove says. “We know this virus. Hantaviruses have been around for quite a while,” she told reporters on May 7 — whereas the virus that causes COVID was new.

And unlike COVID or flu, which spread easily between people, hantavirus “spreads very, very differently,” Van Kerkhove says.

You can catch the flu or COVID by being near an infected person who is talking, coughing or sneezing. What we know about the Andes virus from previous outbreaks is that “it’s really only been between people who are in really close contact with each other for prolonged periods of time, which indicates that it’s probably not something that spreads very efficiently,” Debbink says.

What’s more, she adds, because the outbreak occurred on a boat, the situation is pretty well contained, and the contacts of the people infected are being traced. “It’s not the same where we’re all of a sudden seeing all these cases pop up that aren’t being controlled,” Debbink says.

“With this current news cycle, there are a lot of things that can cause panic. I don’t think we are at that place where panic is necessary,” Agnelli adds. “I think just watchful surveillance and keeping a well-trained eye on the situation is definitely great advice.”

6. How common is hantavirus?

Hantavirus is a relatively uncommon virus, with around 10,000 to 100,000 infections reported each year globally, according to an article in the journal BMJ. 

The CDC has been tracking hantaviruses since 1993. From 1993 to 2023 — the latest data available — there have been 890 cases in the U.S., mostly in the western and southwestern regions of the country.

7. Does a mask prevent hantavirus spread?

If you’re in contact with a sick person, “a mask could help limit the spread,” Agnelli says.

8. How do I stay safe on a cruise ship?

It’s important to remember that “a hantavirus outbreak on a cruise ship is really unheard of,” Debbink says. Other outbreaks, such as norovirus, are more common.

To lower your risk of getting sick on a cruise, make sure you’re up to date on your COVID and flu shots, “because those are things that are much more easily transmitted,” Debbink says.

Another tip: Stay on top of hand washing. “And it doesn’t hurt to pack a mask, just in case you are around people who are sick,” Debbink adds.

Editor's note: This story, first published May 8, 2026, has been updated to reflect new information. 

Rachel Nania is an award-winning health editor and writer at AARP.org, who covers a range of topics including diseases and treatments.