Hantavirus is a respiratory disease that’s spread through infected rodents. Individuals typically contract the disease by coming into contact with rodent feces, urine, or saliva. These can become airborne when disturbed by cleaning or other activities. Though the infected are occasionally aware of having contact with rodents or rodent secretion, many encounter these hazardous particles unknowingly. You can contract the hantavirus anywhere, but it’s much more likely in certain areas.

Where Do Hantavirus Outbreaks Occur?

U.S. hantavirus outbreak map

Notably, 96 percent of hantavirus cases are reported in states west of the Mississippi River. California, Arizona, Colorado, and New Mexico have the highest number of reported cases. New Mexico and Colorado have each had more than 100 cases of hantavirus. Washington state has seen 50 cases of the hantavirus, while Montana and Texas each report more than 40 instances of the disease.

How Many Hantavirus Cases Occur in the United States?

National surveillance for the hantavirus began in 1993. According to the CDC, between 1993 and January 2017, 697 cases of hantavirus were identified in the United States. Once national reporting began on the disease, an additional 31 cases were retrospectively identified, having occurred before 1993.

Who is Impacted by the Hantavirus?

Anyone can contract the hantavirus. It’s impacted patients between the ages of five and 84. The mean age of patients in the United States is 38. Of those who have contracted the hantavirus, 63 percent were male and 37 percent were female.

What Major Outbreaks Have Occurred in the United States?

The hantavirus first gained national attention in the United States in 1993, with an outbreak in the Four Corners region. This area around Arizona, Colorado, New Mexico, and Utah saw 13 deaths during the outbreak, exhibiting a mortality rate of 50 percent. Among them were a 19-year-old marathon runner and his young fianc√©. The couple’s deaths underscored how hazardous the disease is, even to otherwise healthy individuals. The outbreak occurred as the result of a surge in the deer mice population in the area.

In years since, Arizona has remained a major site of Hantavirus cases. Since 1993, over 700 cases of Hantavirus have been confirmed in the United States. Of these, 78 were found in Arizona. Arizona has the third-highest incidence of Hantavirus cases in the United States. After the Four Corners outbreak, it was found that about 30 percent of deer mice in the area carried the virus. Mice that have the virus do not appear sick, so residents must always be vigilant about protecting themselves from the disease.

Where Does Hantavirus Occur Worldwide?

Globally, hantavirus outbreaks are most common in Bolivia, Argentina, Chile, Brazil, Paraguay, Ecuador, Panama, Uruguay, and Venezuela. Outbreaks are often caused by land-use change which can stir up rodent feces. Environmental factors like an increase in rainfall or the flowering of bamboo have also been linked to outbreaks.

If you’re concerned about a hantavirus outbreak, the most important factor to consider is exposure to rodents that may carry the disease. If there is a known increase the rodent population in an area, it’s especially important to be aware of this disease.