Health officials have confirmed that 18 American passengers who were exposed to a deadly hantavirus outbreak on a cruise ship have safely returned to the United States. The U.S. State Department organized a medical airlift from the Spanish island of Tenerife on May 10, bringing the travelers home for monitoring and treatment.

Two of these passengers are currently being treated in specialized biocontainment units. According to the Health and Human Services X account, this is being done “out of an abundance of caution.” One person has tested positive for hantavirus, while the other has developed mild symptoms. The remaining 16 Americans are receiving care at an ASPR Regional Emerging Special Pathogen Treatment Center in Omaha, Nebraska, and two others are at a similar facility in Atlanta, Georgia.

This event has sparked public concern and raised questions about whether we could be facing another global health crisis. However, infectious disease experts strongly emphasize that the risk to the general public remains extremely low. Understanding why requires a closer look at the virus itself, how it spreads, and the unique circumstances of this outbreak.

What Happened on the Cruise Ship?

The outbreak occurred aboard the Dutch-flagged expedition cruise ship m/v Hondius. The vessel departed from southern Argentina on April 1 with approximately 150 passengers and crew members on board. The ship was on a journey across the Atlantic Ocean. Just 11 days into the voyage, a 70-year-old man died after developing fever, headaches, and abdominal pain.

As more passengers began to fall ill, the World Health Organization (WHO) stepped in and officially identified the ship as the site of a hantavirus outbreak. As of May 12, the number of confirmed cases linked to the ship has risen to 11, according to the WHO. Three deaths have been confirmed: a Dutch married couple and a German national.

All remaining passengers have now left the ship and are being sent back to their home countries, according to the latest statement from Oceanwide Expeditions, the company that operates the vessel.

What Is Hantavirus and How Do People Usually Get It?

Hantavirus is a family of viruses that can cause serious respiratory illness in humans. The most common way people become infected is through contact with infected rodents, specifically mice and rats. The virus is present in the urine, droppings, and saliva of these animals.

When contaminated dust or debris from rodent waste is stirred up and inhaled, a person can become infected. This is why outbreaks are often linked to activities like cleaning out sheds, cabins, or other spaces where rodents have been living. The virus does not spread through the air like the flu or the common cold in most circumstances.

However, there is one important exception. A specific strain of hantavirus called the Andes virus, which is found in South America, has been shown to spread from person to person. This is extremely rare compared to other viruses, but it has been documented in the past.

Why Experts Believe Human-to-Human Transmission Occurred on the Ship

The leading theory among health officials is that a person carrying the Andes virus boarded the ship in South America and then passed it on to other passengers during the voyage. This would explain how multiple people became infected in a short period of time.

“Previously, we’ve seen person-to-person spread with Andes virus in situations such as close household contacts or at a large social gathering,” said Steven Bradfute, PhD, an associate professor at the University of New Mexico Health Sciences Center who specializes in hantavirus research. “There’s nothing here that is remarkably different from what we’ve seen in the past.”

Cruise ships are known to be environments where viruses can spread more easily. The close quarters, shared dining areas, and common spaces create conditions that facilitate transmission. This has been seen with other illnesses like norovirus, which frequently causes outbreaks on cruise ships.

Dr. Robert Glatter, an emergency medicine physician at Lenox Hill Hospital in New York City, explained that the confined environment likely played a key role. “The most plausible explanation is that the passengers of the cruise ship likely became infected before boarding the cruise, then human-to-human transmission occurred among close contacts,” he said. “The confined ship environment with close quarters and shared spaces likely facilitated transmission between passengers in ways that wouldn’t occur in typical community settings.”

Why This Is Not the Next Pandemic

Many people are understandably worried after living through the COVID-19 pandemic. The idea of another virus spreading rapidly around the world is frightening. However, experts say the Andes virus is fundamentally different from the coronavirus that causes COVID-19.

“We do have the advantage of historical comparison and what we’re seeing is that Andes virus transmission is much less efficient than what we were seeing in the early stages of COVID,” said Lina Moses, PhD, an epidemiologist and disease ecologist at Tulane University who specializes in rodent-borne diseases.

The key difference is that the Andes virus does not spread easily through casual contact. You are unlikely to catch it by simply walking past someone in a grocery store or sitting near them on public transportation. Transmission requires extended, close contact with an infected person who is already showing symptoms.

“When you compare it to what we see with SARS-CoV-2, the common cold, or influenza, it’s not even in the same ballpark,” Bradfute said. “That doesn’t mean we are dismissing it; these are dangerous viruses, but the transmissibility is not in the same ballpark.”

Understanding the Incubation Period and Asymptomatic Spread

One reason for public concern is the incubation period of the Andes virus, which can range from 4 to 42 days. This means a person could be exposed to the virus and not show symptoms for up to six weeks. During the COVID-19 pandemic, we learned that people could spread the virus before they ever felt sick. This raised fears that the same could be true for hantavirus.

However, experts say this is unlikely with the Andes virus. Research shows that the highest amount of virus in a person’s body occurs during the early stage of symptoms, when they have a fever and respiratory problems. This means that people who are most likely to transmit the virus are also the ones who are sick enough to seek medical care and be isolated.

“The viral load appears highest during the early symptomatic period when patients experience fever and respiratory symptoms,” said Glatter. “This pattern means that severely ill patients — those most likely to transmit the virus — are also most likely to be hospitalized and isolated, naturally limiting transmission opportunities.”

What This Means for the General Public

For the average person, the risk of encountering hantavirus remains extremely low. The Andes virus is primarily found in rural areas of South America, particularly in Argentina and Chile. It is not circulating in the United States or Europe. The outbreak on the cruise ship was a rare and isolated event involving a specific group of travelers.

Experts are not changing their own travel plans. “I’m not changing any of my travel plans,” Bradfute said. “These viruses are dangerous. They’re to be taken seriously. But from what we know of this virus and what we’re seeing so far, there’s nothing here that is concerning for a pandemic at this point.”

Moses added that the fact that more suspected cases are being identified is actually a good sign. “It’s not surprising we’re starting to see more suspected cases. That means that the process is working right. They are monitoring people effectively and identifying people as they become ill.”

Practical Takeaways for Readers

While the risk to the general public is low, there are some practical steps you can take to stay informed and protect yourself:

• Understand the real risks: Hantavirus infection in the United States is almost always linked to contact with wild rodents, not other people. If you live in or travel to rural areas, avoid disturbing rodent nests or cleaning enclosed spaces without proper protective gear.
• Stay informed about travel advisories: If you are planning travel to South America, check with the Centers for Disease Control and Prevention (CDC) and the World Health Organization for any health notices related to hantavirus.
• Know the symptoms: Early symptoms of hantavirus include fever, muscle aches, fatigue, headache, and abdominal pain. These can progress to coughing and shortness of breath. If you develop these symptoms after potential exposure, seek medical attention immediately.
• Do not panic: The monitoring and response efforts seen in this outbreak are a sign that public health systems are working. The fact that 18 Americans were safely airlifted and placed in appropriate care shows that protocols are in place to handle these rare events.
• Trust expert guidance: Infectious disease specialists have studied hantavirus for decades. They understand its transmission patterns and are confident that it does not pose a pandemic threat. Rely on information from reputable health organizations.

The Bottom Line

The hantavirus outbreak on the m/v Hondius cruise ship is a serious situation for those directly affected. Three people have died, and several others are receiving medical care. Health officials are closely monitoring all passengers and crew members who were on board.

However, this event does not signal the beginning of a new global health crisis. The Andes virus, while dangerous, does not spread easily between people. It requires close, extended contact with someone who is already sick. The conditions on a cruise ship may have allowed for transmission in this isolated case, but that does not mean the virus will spread widely in the general population.

As Moses put it, “I think we’re actually in very good shape.” The public health system is doing what it was designed to do: identify cases, isolate patients, and prevent further spread. For the vast majority of people, there is no reason to change daily routines or alter travel plans. The risk remains low, and experts are confident that this outbreak will be contained.

Source: Healthline