The doctor who is now isolated inside a specialized biocontainment unit in Nebraska has shared new details about his time aboard a cruise ship hit by a hantavirus outbreak. He is raising an important question: Could he and other passengers have already been infected without knowing it?

Dr. Stephen Kornfeld, an Oregon-based oncologist currently at the University of Nebraska Medical Center (UNMC) in Omaha, told CNN that he and several other passengers experienced flu-like symptoms in early April. At the time, no one suspected hantavirus. But now, with the outbreak confirmed, those weeks of illness are being reexamined.

“I had three days of night sweats, a lot of chills, some mild respiratory symptoms, and a lot of fatigue,” Kornfeld said in the interview. The night sweats and breathing issues eventually went away, but the fatigue stuck around for more than two weeks.

At the time, Kornfeld said it felt like a normal virus you might catch while traveling on a ship. But because hantavirus tests are not as “straightforward to interpret” as people might think, he explained, “it may never be known if that illness, which others also had, was hantavirus” or something else entirely.

What is Hantavirus and Why Does It Cause Concern?

Hantavirus is a rare but serious viral disease that spreads through contact with infected rodents, particularly deer mice. People usually catch it by breathing in dust that contains droppings, urine, or saliva from an infected rodent. The virus does not spread from person to person in most cases, but the current outbreak on the cruise ship has raised questions about unusual transmission patterns.

In the United States, hantavirus is most commonly reported in rural areas of the Southwest, where people come into contact with rodents in sheds, cabins, or barns. It is extremely rare on cruise ships. The virus can cause hantavirus pulmonary syndrome (HPS), a severe respiratory illness that can be fatal. Early symptoms include fever, muscle aches, fatigue, and dizziness. As the disease progresses, it can cause coughing and shortness of breath as the lungs fill with fluid.

According to the Centers for Disease Control and Prevention (CDC), about one in three people who develop HPS die from the illness. That is why doctors and public health officials take any potential case very seriously. There is no specific cure or vaccine for hantavirus. Treatment focuses on supportive care, often in an intensive care unit, to help patients breathe and maintain organ function.

Testing Challenges and the “Faintly Positive” Result

Kornfeld’s case highlights how tricky hantavirus testing can be. Along with members of the ship’s staff, he had nasal swabs taken and frozen in early May. Those samples were later sent to a lab in the Netherlands for processing. One test came back negative. The other test came back “faintly positive,” he noted. Those results were shared with the CDC, “and here I am,” he said.

Kornfeld acknowledged that this “faintly positive” result could mean two very different things. It might indicate that he is about to get sick with hantavirus. Or it could mean that he has already been infected and recovered — without ever knowing he had the virus.

The latter scenario would be “good news … but it’s still possible that that test represents evolving disease, and I will get symptoms down the road,” he explained. That uncertainty is the reason he is now in isolation.

Isolation in a Biocontainment Unit: Safety First

Kornfeld is currently the only passenger at UNMC who is being housed in a biocontainment unit. Fifteen other passengers remain in quarantine at the same facility, but they are not in the specialized unit. Two other American passengers were flown to Emory University in Atlanta after one partner developed symptoms. That individual has since tested negative, according to the Department of Health and Human Services.

“I’m not ill, but the term I hear a lot is ‘abundance of caution,'” Kornfeld said. “This is a very secure facility. So if I am to get sick and spill virus, there’s no way that virus is getting out of this building.”

The oncologist described his isolation room as looking like any other hospital room on the inside. But it has multiple layers of biocontainment, including “many doors” and “clean rooms” — small vestibules between the isolation room and the rest of the facility where medical staff can safely change into and out of protective gear.

“It’s a little weird being here by myself,” he admitted. But he sees doctors and nurses often, and stays connected through WhatsApp. “It’s really amazing how quickly time flies. Many weeks of this? Well, we’ll see how that goes.”

How Did the Doctor Become Exposed?

Kornfeld became the ship’s de facto doctor after the hired medical professional became sick. In that role, he had close contact with passengers who were ill. He described two key points of contact on the ship. First, there was “a gentleman who was sick, was around us, and socializing with us.” Second, he had contact with other sick people in early May.

“Now, maybe I’d already had the disease, or maybe I hadn’t. There’s a lot of speculation, but I had two different contacts, which certainly puts me at higher risk,” he pointed out.

When asked whether hantavirus might spread through more casual contact or even through the air, Kornfeld called the idea “very speculative.” He noted that he did not have direct intimate contact with the original patient, but “a lot of us had frequent, mild contact with each other.” He added that it is possible this contact was “repetitive enough that it allowed transmission.”

What Experts Generally Say About Hantavirus Transmission

Public health experts emphasize that hantavirus is not typically spread between people. The vast majority of cases occur when someone inhales aerosolized particles from rodent droppings. Person-to-person transmission has been documented in only one known outbreak, in Argentina in 1996, involving a strain of the virus called Andes virus. That strain is not found in North America.

However, the current cruise ship outbreak is unusual, and experts are still investigating how the virus spread among passengers. The CDC is conducting tests to determine the specific strain involved and whether any unusual transmission patterns exist. Results are expected later this week.

Dr. William Schaffner, an infectious disease specialist at Vanderbilt University Medical Center, has said in past interviews that while hantavirus is rarely a concern for most travelers, outbreaks in confined spaces like cruise ships deserve close attention. “Any time you see a cluster of a rare disease, you need to investigate thoroughly,” he has noted. “The public health response must be aggressive to prevent further spread.”

How This Affects Readers and Travelers

For most people, the risk of catching hantavirus is extremely low. The virus does not circulate widely in the general population, and it is not something that most doctors would consider when diagnosing a patient with flu-like symptoms. However, this case serves as an important reminder about the value of thorough testing and quarantine protocols when dealing with unusual illnesses.

If you are planning a cruise or any type of travel, here are some practical takeaways:

• Pay attention to onboard health alerts. Cruise ships are required to report outbreaks of certain illnesses to the CDC. Check the agency’s Vessel Sanitation Program website before booking.
• Wash your hands frequently. Many viruses spread through surface contact. Hand hygiene is one of the best ways to protect yourself.
• Report symptoms early. If you develop fever, chills, or respiratory issues while traveling, inform the ship’s medical staff immediately. Early detection helps protect everyone onboard.
• Understand quarantine procedures. If you are asked to isolate, it is not a punishment. It is a precaution to prevent potential spread of disease. Follow all instructions from medical professionals.
• Know that hantavirus is rare. While this story sounds alarming, the odds of encountering hantavirus on a cruise ship or anywhere else are extremely small. Most flu-like illnesses are caused by common viruses like influenza or rhinovirus.

What Happens Next for Dr. Kornfeld?

For now, Kornfeld remains in the biocontainment unit, waiting for test results from the CDC and other labs. He appeared healthy during the CNN interview. “I feel wonderful, 100%,” he said.

If his test results come back negative, he will likely be released from isolation. If they come back positive, doctors will monitor him closely for any signs of hantavirus pulmonary syndrome. Because he is already in a specialized facility, he would receive immediate care if his condition changes.

The CDC and other public health agencies are also working to trace the source of the outbreak on the ship. They are testing environmental samples and interviewing passengers to determine how the virus was introduced and how it spread. This information will help prevent future outbreaks and improve safety protocols for cruise ships and other confined environments.

Practical Takeaways for Your Health

While this story is about a rare virus on a cruise ship, it carries broader lessons that apply to everyone:

• Listen to your body. If you have unusual or persistent symptoms, especially after travel, see a doctor. Tell them where you have been.
• Trust public health measures. Isolation and quarantine can feel inconvenient or scary, but they are designed to protect you and others. The “abundance of caution” approach saves lives.
• Stay informed. Reliable sources like the CDC, the World Health Organization, and trusted health news websites provide accurate, updated information about disease outbreaks.
• Don’t panic. Rare diseases make headlines because they are unusual. Your everyday health risks — like seasonal flu, heart disease, and diabetes — deserve far more attention than a one-in-a-million virus.

As for Kornfeld, he remains calm and in good spirits. “I feel wonderful, 100%,” he repeated. For now, he waits. And the world watches, learning more about a virus that most people will never encounter — but that reminds us all of the importance of vigilance, science, and compassion in the face of the unknown.

Source: MedPage Today