A rare and potentially deadly virus carried by rodents has been thrust into the global spotlight after a suspected outbreak on a cruise ship in the Atlantic Ocean left three people dead and several others ill. Hantavirus refers to a family of viruses spread primarily through contact with infected rodents — including mice and rats — and their urine, droppings, and saliva. While human infections are uncommon, they can be severe, leading to life-threatening respiratory or kidney complications.
The current outbreak aboard the MV Hondius, a cruise ship operated by Oceanwide Expeditions, has raised urgent questions about the virus, how it spreads, and what can be done to prevent it. With the World Health Organization confirming one case and suspecting five others, here is everything you need to know about hantavirus.
How Hantavirus Unfolds: A Look at the Virus and Its Transmission
Hantaviruses have likely been circulating for centuries, with documented outbreaks in Asia and Europe. According to the U.S. Centers for Disease Control and Prevention, the viruses cause two distinct illnesses: Hantavirus Pulmonary Syndrome (HPS), which primarily affects the lungs, and Hemorrhagic Fever with Renal Syndrome (HFRS), which targets the kidneys.
Transmission most commonly occurs when people inhale airborne particles from dried rodent droppings, urine, or nesting materials that have been disturbed. This typically happens in enclosed, poorly ventilated spaces such as homes, cabins, sheds, or — as in the case of the MV Hondius — ship compartments where rodents may be present. In rare instances, the virus can also spread through a rodent bite or scratch, or even between humans, though human-to-human transmission remains extremely uncommon.
Australian virus researcher Paul Griffin told the Australian News Agency that approximately 150,000 to 200,000 hantavirus infections are identified worldwide each year. "It is very rare that it spreads from human to human," he noted.
Timeline: From the MV Hondius Departure to a Deadly Outbreak
The MV Hondius departed from Ushuaia, Argentina, approximately three weeks ago, carrying an estimated 150 passengers on an expedition cruise that included stops in mainland Antarctica, the Falkland Islands, South Georgia, Nightingale Island, Tristan da Cunha, St. Helena, Ascension Island, and Cape Verde. During the journey, passengers began showing flu-like symptoms that rapidly escalated.
On the voyage, a 70-year-old Dutch man was declared dead upon arrival in St. Helena. His 69-year-old wife collapsed at Johannesburg's O.R. Tambo International Airport while attempting to fly back to the Netherlands and later died at a medical facility. A third passenger, a German national, died onboard on Saturday. A British passenger who became ill was transported to a hospital in South Africa, where lab results confirmed hantavirus infection. Two symptomatic crew members remain aboard the ship off the coast of Cape Verde, where local authorities have assessed their condition but have not authorized disembarkation.
Why Hantavirus Matters: Understanding the Symptoms and Severity
Early detection of hantavirus is notoriously difficult because its initial symptoms closely resemble those of the flu. Dr. Sonja Bartolome of UT Southwestern Medical Center in Dallas explained: "Early in the illness, you really may not be able to tell the difference between hantavirus and having the flu." Symptoms typically appear one to eight weeks after exposure and include fever, fatigue, muscle aches (particularly in the thighs, hips, back, and shoulders), headaches, dizziness, chills, and abdominal issues such as nausea, vomiting, diarrhea, and abdominal pain.
As the disease progresses, HPS patients develop coughing and shortness of breath four to ten days after the initial phase, as the lungs fill with fluid. The CDC reports that HPS is fatal in about 38% of cases in the United States. Meanwhile, HFRS can cause low blood pressure, acute shock, internal bleeding, and acute kidney failure, with fatality rates ranging from less than 1% to 15% depending on the viral strain.
There is currently no specific antiviral treatment or cure for hantavirus infections. Patients receive supportive care, which may include oxygen therapy, mechanical ventilation, and dialysis for kidney failure. Early medical attention significantly improves survival chances.
Where Things Stand Now: The MV Hondius and Ongoing Investigations
The MV Hondius remains off the coast of Cape Verde as health authorities work to manage the situation. Oceanwide Expeditions has stated that its priority is ensuring the two symptomatic crew members onboard receive adequate and expedited medical care. The WHO has launched multiple investigations, and sequencing of the virus is underway to determine the specific strain involved. The WHO has stated that the risk to the general public remains low.
This is not the only high-profile hantavirus case in recent memory. In February 2025, Betsy Arakawa, the wife of legendary actor Gene Hackman, died of hantavirus pulmonary syndrome at their home in Santa Fe, New Mexico. An autopsy confirmed the diagnosis, and evidence of rodent activity was later found on the property, which may have been the source of exposure.
What Happens Next: Prevention and the Road Ahead
Prevention remains the most effective strategy against hantavirus. The CDC recommends eliminating or minimizing contact with rodents by sealing holes and gaps in homes and garages, placing traps, and removing easy food sources that attract rodents. When cleaning areas with rodent activity, experts advise never sweeping or vacuuming droppings, as this can aerosolize the virus. Instead, wear rubber or plastic gloves, spray the area with a bleach solution or disinfectant until thoroughly wet, and then wipe up using paper towels.
Public health experts continue to study hantaviruses, and despite decades of research, many aspects of the disease remain poorly understood. As the situation aboard the MV Hondius demonstrates, even in the modern era, ancient viruses carried by rodents remain a serious public health concern requiring vigilance, rapid response, and public awareness.
Key Takeaways About Hantavirus
- What it is: A family of viruses carried by rodents that can cause severe respiratory or kidney disease.
- How it spreads: Primarily through inhaling airborne particles from rodent urine, droppings, or saliva.
- Symptoms: Flu-like signs including fever, muscle aches, and fatigue, progressing to breathing difficulty or kidney failure.
- Mortality: HPS is fatal in about 35-38% of cases; HFRS ranges from 1% to 15% depending on the strain.
- Treatment: No specific cure exists — supportive care such as oxygen, ventilation, and dialysis is the standard.
- Prevention: Avoid rodent contact, seal entry points, and use wet cleaning methods with disinfectant when dealing with droppings.
