Hantavirus Cruise Ship Outbreak: What Passengers and the Public Need to Know Now
Passengers aboard the MV Hondius, a cruise ship currently dealing with a hantavirus outbreak, remain at sea and are expected to dock in the Canary Islands on Sunday. While this situation may sound alarming, medical experts say it is important to understand what is happening, how it affects passengers and healthcare workers, and what the general public should know about this rare but serious virus.
To help explain the situation, MedPage Today spoke with Dr. James Lawler, an expert in outbreak response at the University of Nebraska Medical Center’s Global Center for Health Security. Dr. Lawler previously led teams on the Diamond Princess cruise ship during the early days of the COVID-19 pandemic. He shared insights on what happens next, how Americans who already returned home are being monitored, and what risks healthcare workers may face.
Why Does It Take So Long for a Ship to Dock During an Outbreak?
When a ship reports an infectious disease outbreak, it often faces delays before it can dock. Dr. Lawler explains that this is a common problem. Fear among the public and pressure on politicians often lead to decisions that are not always in the best interest of controlling the outbreak or caring for sick people.
“That often works against public health workers and healthcare workers trying to manage cases and contain the outbreak,” Lawler said. Delaying the ship’s docking until Sunday means responders and epidemiologists cannot get on board to conduct a full investigation. It also means that if more passengers become seriously ill, they may not be able to receive critical care quickly.
Hantavirus is particularly dangerous because symptoms can appear suddenly. The incubation period—the time between exposure and when symptoms start—can be as long as six or seven weeks. Once a person begins to feel sick, their condition can worsen rapidly.
How Quickly Can Hantavirus Become Serious?
Dr. Lawler notes that hantavirus is a difficult disease to manage because of its long incubation period and the speed at which patients can deteriorate. In the early stage, people may have a few days of mild symptoms like fever, headache, and muscle aches. This is called the prodromal phase. During this time, the lungs are not yet affected.
But when the disease enters its severe phase, the heart and lungs begin to fail. Patients may start coughing or feel short of breath. Within 24 hours, they can go from breathing normally on room air to needing a ventilator with a breathing tube.
“That means they may go from being OK to being on a ventilator within a day,” Lawler said. This rapid decline makes it critical for patients to have access to intensive care as soon as possible.
What Is the Expected Response on the Ship?
Every shipboard outbreak is different, according to Lawler. The MV Hondius is much smaller than the Diamond Princess, so the response will be smaller and likely more organized. However, there will still be some improvisation because each situation is unique.
One advantage this time is that health officials already know the virus involved—Andes virus, a type of hantavirus found in South America. They understand how it spreads and what precautions to take. This makes it easier for response teams to adopt the right infection prevention measures. Still, Lawler admits there are many open questions about Andes virus specifically.
He also points out that lessons learned from COVID-19 have changed how experts think about infection risk. “We’ve learned that the rigid approach we used to bucket different types of infection risk probably didn’t reflect how things happen in nature,” he said. Now, experts think about risk as a continuum rather than a strict category.
How Will Passengers Be Brought Home?
Bringing passengers home will involve multiple countries and careful planning. Each person will undergo a detailed risk assessment. Officials will ask: Did you have contact with known cases? Did you have contact with people who showed symptoms?
Because the ship is small and passengers have been together for weeks, mixing and sharing meals, it is nearly impossible to say anyone is at zero risk. “I think anybody who was on that ship is probably going to need to be in quarantine, or at least under close observation, for a period of time,” Lawler said.
Some people may need to stay in a dedicated quarantine unit where they can be watched closely. Others may be allowed to monitor themselves at home, as long as they do not put others at risk.
For U.S. passengers, the State Department typically handles repatriation using chartered aircraft. These planes are staffed with trained personnel who know how to move people who have been exposed to high-risk infections. This approach was used during the 2014 Ebola crisis and in many other situations.
What About Americans Who Already Returned Home?
Several American passengers left the ship before the outbreak was fully recognized and have already returned to the United States. This is a concern, Lawler says. Public health officials are working hard to track down these individuals, assess their risk, and make sure they are not showing symptoms. They are also placing them under some form of monitoring.
The long incubation period means these passengers are still within the danger window. Their clock for observation starts at their last point of contact with a potentially infected person. Since that contact was recent, they could still develop symptoms for another month or more.
Lawler emphasizes that this is not the next COVID-19 pandemic. “This is not a virus that has explosive transmission potential and is going to run through a community quickly,” he said. However, it does pose a risk to people who have had close contact with sick individuals. And if someone does get sick, the disease can be very severe, often requiring intensive care.
Are U.S. Healthcare Workers at Risk?
If any of these returning passengers seek medical care, healthcare workers could be at risk. Historically, Andes virus has not been as easily transmitted in healthcare settings as Ebola, SARS-CoV-2, or influenza. However, there have been documented cases of transmission to healthcare workers and other patients.
“If the passengers being monitored seek care per the correct protocols, how would they be treated?” Lawler asks. He explains that Andes virus is considered a high-consequence pathogen. It has a person-to-person transmission risk, a lethality rate of about 30%, and no specific medical treatments or vaccines. This puts it in the same category as Ebola, Marburg, and Lassa viruses.
In most cases, patients with Andes virus infection would be moved to a biocontainment unit. These are specialized facilities with dedicated infrastructure and teams trained to manage high-risk infections. There are 13 top-tier biocontainment units in the United States, developed after the 2014 Ebola crisis. A second tier of facilities is also being developed.
Lawler warns that the United States has limited capacity for providing isolation care, especially for infections that require aggressive precautions against contact, droplet, and airborne transmission. “It is very demanding in terms of the resources required from a hospital to support this,” he said.
What Is Being Done to Improve Hospital Preparedness?
Dr. Lawler is involved in a project called ISTARI, which aims to improve the nation’s ability to manage high-consequence infectious diseases. The problem, he says, is that isolation rooms are expensive to build, PPE supply chains are still fragile, waste management is challenging, and most hospitals cannot afford a dedicated biocontainment team.
“All of that means it’s really difficult to take care of these patients using our current paradigm,” Lawler said. “And if it’s this challenging in the U.S., you can only imagine how challenging it is in resource-limited settings.”
The ISTARI project took a creative approach. Instead of having healthcare workers wear heavy PPE and constantly put it on and take it off, the team designed a device that puts the protection around the patient. Healthcare workers can then interact with the patient through a barrier without having to don and doff gear repeatedly.
The device, now marketed by a company called CareCubes, received FDA clearance in 2024. It is small enough to be used in an emergency department, clinic, or small hospital. Several hospitals have already purchased it, and some of the 13 national biocontainment facilities are early adopters.
Lawler hopes these facilities will serve as subject matter experts for smaller hospitals in their regions. The device is not just for rare cases like Ebola. It can also be used for tuberculosis, measles, influenza, and even avian influenza. “All of those would benefit from early and aggressive isolation care,” he said.
The goal is to make the device easy enough to integrate into routine care. “Somebody comes in with a fever and a cough. Until they get worked up and characterized, you could care for them through one of these devices,” Lawler explained. “Now your healthcare workers are safe. All of the other patients and bystanders around them are safe. It just allows you to deliver much better care in a way that limits opportunities for outbreaks and spread.”
Practical Takeaways for Readers
– Hantavirus is rare but serious. It has a long incubation period (up to 7 weeks) and can progress quickly from mild symptoms to severe respiratory failure.
– If you have been on a cruise or in close contact with someone who may have been exposed, monitor for symptoms like fever, muscle aches, cough, and shortness of breath. Seek medical care immediately if symptoms appear.
– The risk to the general public is low. This is not a pandemic-level threat. However, healthcare workers should follow strict infection control protocols when treating suspected cases.
– Hospitals are working to improve their ability to isolate and treat high-risk infections. New devices like the CareCubes isolation system may help smaller facilities provide safe care.
– If you travel internationally, stay informed about disease outbreaks at your destination. Follow public health guidance and report any symptoms after returning home.
The situation on the MV Hondius is being managed carefully, and health officials are taking steps to protect passengers, crew, and the public. While hantavirus is a serious illness, it is not easily spread, and with proper precautions, the risk can be contained.
Source: MedPage Today
