Potential Hantavirus Case Reported in Illinois
State health officials in Illinois have reported a potential case of hantavirus in a resident from northern Illinois. However, this case appears to be unrelated to the recent outbreak linked to the cruise ship MV Hondius.
The Illinois Department of Public Health (IDPH) made an announcement on Tuesday indicating that they are currently investigating this first possible hantavirus case of the year.
According to IDPH, the individual does not have any known connections to the MV Hondius outbreak and has not traveled internationally. They reside in Winnebago County and may have been exposed to a North American strain of the virus while cleaning a space with rodent droppings.
Notably, the North American strains of hantavirus do not spread from person to person, which differs from the Andes strain responsible for the cruise outbreak.
IDPH emphasized that the overall risk of contracting hantavirus remains quite low for residents of Illinois. Fortunately, the individual is not severely ill and is recovering from mild symptoms that haven’t required hospitalization.
The IDPH is collaborating with the CDC for further testing to confirm whether the resident is indeed positive for hantavirus. This confirmation process might take up to 10 days, as the initial antibody tests conducted are not definitive and require a more sensitive test from the CDC.
The department is coordinating efforts with local health agencies, including the Winnebago County Health Department, as well as the CDC.
Since 1993, Illinois has documented seven positive cases of hantavirus, with the most recent case occurring in March 2025. In total, the U.S. has seen 890 cases of hantavirus since surveillance started in 1993.
The strain most frequently identified in the U.S. originates from rodent droppings and is not transmissible between people, according to IDPH. Interestingly, the rodent species typically responsible for the Andes strain, the long-tailed pygmy rice rat, is not found in the U.S.
While the CDC has reached out to states with residents linked to the cruise ship, Illinois has not yet been contacted regarding this matter.
