90-Second Read: Hantavirus cases map shows where virus has been detected

While Hantavirus's lethality is concerning, its weeks-long incubation period makes controlling cases and contact tracing difficult. Only 11 cases of Hantavirus have been identified, and nine have been confirmed. Health officials in Washington also said they were monitoring two people who sat near a passenger from the cruise ship who tested positive for Hantavirus. At the same time, state health officials in Illinois are investigating a possible Hantavirus infection in a Winnebago County resident, unrelated to the cruise ship and involving a different strain of the virus.

In the United States, no widespread domestic outbreak has been confirmed, but multiple states are monitoring individuals who have been exposed to Hantavirus or are exhibiting symptoms. The Illinois Department of Public Health (IDPH) is investigating a possible Hantavirus case in Winnebago County, located near Rockford. While more cases linked to the cruise ship may still emerge due to the virus's long incubation period, officials say there is no sign of sustained, widespread transmission. Three people have died from the virus since the outbreak was identified on the cruise ship.

But authorities are stressing that the overall risk to the general public remains extremely low, in part because Hantavirus requires close, prolonged contact with another person to transmit between humans. In the United States, most Hantavirus infections are associated with exposure to rodent droppings in enclosed or poorly ventilated spaces, such as cabins, barns or homes. The virus is rare but can cause a severe and potentially fatal illness known as Hantavirus Pulmonary Syndrome (HPS). Health officials stress that most North American strains of Hantavirus do not spread from person to person, which is a key reason experts say the current risk to the general public remains low.

Hantavirus is a family of viruses most commonly transmitted to humans through contact with infected rodent urine, feces or saliva, often when contaminated dust becomes airborne and is inhaled. Hantavirus symptoms often begin with flu‑like signs but can rapidly progress to life‑threatening respiratory illness. None of them were on the ship, but had contact with someone who tested positive for the virus.