Health officials have revealed unexpected spots where Americans could be exposed to hantavirus, a rat-borne illness at the center of an outbreak on the MV Hondius cruise ship that has caused 11 illnesses and three deaths. Eighteen American passengers are under medical monitoring in Omaha and Atlanta as health officials work to contain the rare outbreak.
Low Risk to General Public
Health officials emphasize that hantavirus remains a low risk to the general public. While experts investigate the ship's outbreak, an Illinois resident who was not on the ship is now feared to have contracted hantavirus, according to the Illinois Department of Public Health (IDPH). The agency believes the man caught the virus through contact with rodent droppings.
How Hantavirus Spreads
Hantavirus is mainly spread through contact with infected rodents, particularly deer mice, and their urine, saliva, or droppings, according to the CDC. People typically become infected after breathing in contaminated particles stirred into the air when disturbed, such as during sweeping.
Dr Katherine O'Reilly, medical director at InternationalSOS in the UK, told the Daily Mail: 'A common misconception is that risk comes from casual contact, when in reality it is often linked to specific activities. People may unknowingly increase their exposure when cleaning enclosed or dusty spaces, particularly if rodent urine or feces is present.'
Infections can occur after breathing in particles or touching contaminated surfaces and then touching the nose or mouth. Rodent bites can also spread hantavirus but are less common.
At-Risk Locations
Health officials warn that cleaning in enclosed or poorly ventilated areas where rodents may nest for weeks or months is a likely source of exposure. At-risk locations include:
- Garages, sheds, cabins, attics, barns, and crawl spaces
- Storage units, horse stables, kitchen cabinets, and small spaces behind appliances
- Unused cars, RVs, campers, and boats
Sweeping areas with rodent droppings is one of the top causes of hantavirus exposure, experts warn. The CDC advises against vacuuming or sweeping rodent urine, droppings, or nesting materials to avoid stirring the virus into the air.
Risk Concentration
Dr O'Reilly said: 'Although the current hantavirus situation is drawing attention, the overall risk to the public remains low. Infection is not typically spread through routine person-to-person contact but is most often linked to exposure to infected rodents or their droppings. This significantly limits the likelihood of widespread transmission.'
However, she added: 'It is not a zero risk. Individuals spending time in environments where rodent contamination may be present – such as enclosed, poorly ventilated, or infrequently cleaned spaces – may face a higher level of exposure. This is particularly relevant in specific occupational or environmental settings, meaning risk is concentrated rather than generalized.'
According to the National Park Service, most hantavirus cases occur in spring when people enter buildings that have become heavily infested with rodents over winter.
Prevention and Symptoms
Dr O'Reilly emphasized that in areas with rodents, 'it is important to avoid direct contact, ensure good hygiene and safe food storage, ventilate spaces before cleaning, and use protective measures such as gloves and disinfectant rather than dry cleaning methods.'
While hantavirus is rare, O'Reilly urges awareness of symptoms: 'Early signs can resemble flu – fatigue, fever, headaches, and muscle aches – but may progress to more serious respiratory symptoms. Anyone who has had potential exposure and develops these symptoms, particularly shortness of breath, should seek urgent medical attention, as early supportive care can significantly improve outcomes.'
