Historical Description of Hantavirus
Hantavirus was first identified in the United States in 1993 during an outbreak in the Four Corners region, where Arizona, Colorado, New Mexico, and Utah meet. During that investigation, a new virus strain called Sin Nombre was discovered. Related hantaviruses have already been identified in other parts of the world, particularly in Asia and South America. The virus is ancient, circulating in rodent populations for thousands of years before its ability to infect humans was recognized.
Brief Epidemiology in the United States
Hantavirus infections are rare in the United States, with most cases occurring in Western and Southwestern states. Most reported cases have occurred in states such as Arizona, New Mexico, Colorado, and California.
Nationwide, fewer than 20 cases are typically reported each year, and the virus is exceptionally rare in Jackson County and the Kansas City region.
How Hantavirus Spreads
Hantaviruses spread to humans through contact with infected rodent urine, droppings, or saliva. Infection most commonly occurs when contaminated particles become airborne and are inhaled.
The primary rodent carriers in the United States include deer mice, white-footed mice, and other wild rodents.
The Sin Nombre virus strain found in the United States does not spread from person to person. However, rare person-to-person transmission has been documented with the Andes virus strain in South America.
Incubation Period
The incubation period for hantavirus infection is typically between 1 and 8 weeks after exposure.
Early symptoms often resemble influenza or other viral illnesses and may include:
- Fever
- Fatigue
- Headache
- Muscle aches
- Nausea or vomiting
Some patients develop severe respiratory illness, including fluid buildup in the lungs that requires immediate hospitalization. Although infections are rare, hantavirus can be serious and even fatal in some instances. Anyone experiencing fever, difficulty breathing, or worsening symptoms after possible rodent exposure should seek medical care immediately.
Most Vulnerable Populations
People at highest risk are those with increased exposure to rodents or rodent-infested environments. Higher-risk groups include:
- Farmers and ranchers
- Construction and demolition workers
- Pest control professionals
- Campers and outdoor workers
- Homeowners cleaning rodent-contaminated spaces
People with weakened immune systems may also experience more severe illness.
Geographic location remains one of the most important risk factors, particularly in areas where infected rodent populations are known to occur.
Preventing Hantavirus
There is currently no vaccine or specific cure for hantavirus infection. Treatment is supportive, and early medical care may improve outcomes. Preventing rodent exposure remains the best way to reduce risk. Although hantavirus infections are exceptionally rare in our area, the Centers for Disease Control and Prevention (CDC) recommends taking simple precautions around rodents and rodent-contaminated areas to help reduce potential exposure.
Rodent Control
- Seal holes and entry points around homes and buildings
- Store food securely
- Reduce clutter where rodents may nest
- Maintain clean indoor and outdoor environments
Safe Cleanup
Never sweep or vacuum rodent droppings or nesting materials, as this can spread contaminated particles into the air. Instead:
- Spray contaminated materials with disinfectant
- Allow disinfectant to soak for several minutes
- Use gloves and paper towels to wipe up materials carefully
- Ventilate the area
- Wash hands thoroughly afterward
Occupational Protection
Workers in higher-risk settings should use appropriate protective equipment and follow workplace safety guidance when handling rodent-contaminated materials.
Testing and Surveillance for Hantavirus
Public health agencies continue monitoring rodent populations and human cases to identify potential risks and trends.
Current Outbreak Situations
Globally
A May 2026 outbreak on the MV Hondius cruise ship that set sail from Argentina in March 2026 resulted in at least 3 deaths and multiple cases. Authorities reported that the outbreak involved the Andes virus strain, which has demonstrated rare instances of person-to-person transmission. International public health agencies continue monitoring the situation.
United States
There is currently no active hantavirus outbreak of significant concern in the United States. However, infected rodents and isolated human cases continue to be identified in Western states where hantavirus is naturally present. In January 2026, San Diego County identified a hantavirus-positive Western harvest mouse during routine surveillance activities. Recent deaths associated with hantavirus exposure in the Southwest, including in the Four Corners region, have also renewed public awareness of the disease. The CDC and state health departments continue active surveillance and monitoring efforts nationwide.
Risk to Jackson County
The risk of hantavirus in Jackson County remains very low.
Kansas City’s metropolitan area falls outside the primary regions where hantavirus is most commonly found in the United States. Awareness is still important for individuals traveling to endemic areas, especially rural or outdoor settings where rodent exposure may occur.
At this time, no special public health measures are recommended beyond routine rodent prevention and safe cleanup practices.
Jackson County Public Health will continue monitoring national and international developments and maintaining surveillance protocols. Should any cases be identified locally, public health officials are prepared to respond quickly with investigation and community communication efforts.
For more information, contact the JCPH Communicable Disease hotline at (816) 404-9881.
