9 US Outdoor Destinations Where Hantavirus Risk Is Rising and What Travelers Need to Do Before They Go

Spring and summer travelers are heading back to cabins, parks, and desert campgrounds across the US. Health officials say that also means renewed attention to hantavirus, a rare but often severe disease spread mainly through contact with infected rodent droppings, urine, and nesting material.

The risk is still low for most visitors, but it rises in places where deer mice and other wild rodents commonly enter enclosed spaces. For travelers planning outdoor trips, public health advice is straightforward: avoid stirring up dust, check sleeping areas, and treat rodent signs seriously.

Yosemite National Park, California

Yosemite remains one of the best-known US destinations tied to hantavirus awareness because of past visitor infections linked to rodent exposure in lodging areas. The National Park Service and California health officials have repeatedly stressed that deer mice are common in the Sierra Nevada and can carry the virus without appearing sick.

That matters most in tent cabins, rustic lodging, storage spaces, and little-used buildings where mice can nest. Travelers are most at risk when they sweep or disturb droppings and dried nesting material, sending contaminated particles into the air.

Before a Yosemite stay, officials advise visitors to inspect cabins and tent areas for droppings, chewed packaging, or mouse nests. If signs are present, do not dry sweep. Ventilate the space, use disinfectant or a bleach solution as directed on public health guidance, and wipe up material with gloves.

Mammoth Lakes and the Eastern Sierra, California

The Eastern Sierra, including Mammoth Lakes, has long been watched closely by county and state health departments for hantavirus activity. Local officials have periodically warned residents and visitors that heavy snow years and changing food conditions can affect rodent numbers, especially deer mice in sheds, garages, cabins, and campsites.

For travelers, the concern is not hiking on open trails. It is spending time in enclosed spaces that have been shut up for weeks or months. Vacation rentals, gear sheds, and older cabins can all become nesting spots before guests arrive.

Experts recommend opening doors and windows for at least 30 minutes before cleaning or unpacking. Food should be kept in sealed containers, pet food should not be left out overnight, and trash should be secured. If you are staying in a mountain cabin, report rodent evidence to the owner or property manager immediately.

Four Corners Region, New Mexico

New Mexico remains central to hantavirus surveillance because the first recognized US outbreak of hantavirus pulmonary syndrome was identified in the Four Corners region in 1993. Since then, the state has reported cases almost every year, according to state health updates, with exposure often tied to homes, sheds, and rural buildings.

For visitors, that includes camp structures, roadside cabins, and backcountry shelters in dry high-desert areas. The landscape may feel wide open, but infection risk usually comes from enclosed places where mice have sheltered and left waste behind.

Travelers heading to northwestern New Mexico should avoid sleeping directly on floors in questionable structures and should never shake out dusty tarps or bedding indoors. Public health officials also advise keeping vehicles and coolers free of crumbs, since food scraps attract rodents quickly in desert camp areas.

Northern Arizona High Country

Arizona has reported hantavirus cases over the years, especially in higher-elevation and rural parts of the state where deer mice are common. That puts destinations near Flagstaff, the Mogollon Rim, and forest cabins across the high country on seasonal watch as travelers return for cooler weather and camping.

Rodents often move into cabins, woodpiles, and stored gear during colder months, then remain hidden into spring. Visitors may not notice a problem until they open a storage bin or start cleaning an unused room.

State and county health agencies generally advise travelers to look carefully at mattresses, cupboards, and corners before settling in. Do not vacuum droppings. Wet them down with disinfectant first, wear gloves, and bag waste carefully. Campers should also avoid feeding wildlife and should store food away from sleeping spaces.

Southwest Colorado Cabin Country

Southwest Colorado, including rural parts of La Plata, Archuleta, and Montezuma counties, is another region where hantavirus warnings surface during travel season. Colorado health officials have repeatedly said the disease is rare but serious, with many cases tied to peridomestic exposure, meaning around cabins, homes, outbuildings, and garages.

This matters for vacationers renting mountain cabins or opening seasonal properties after winter. A closed-up cabin with a warm crawl space or accessible pantry can become an easy nesting site for mice long before the first guests arrive.

Travelers should ask hosts whether the property has been recently inspected for rodent activity. On arrival, check under sinks, behind furniture, and inside drawers. If there is evidence of infestation, request another unit rather than cleaning heavily contaminated areas yourself, especially if children or older adults are in the group.

Montana’s Glacier Gateway Towns

Montana health officials have documented hantavirus cases in several parts of the state, and travelers passing through gateway towns near Glacier National Park should be mindful in cabins, bunkhouses, and older motels with seasonal openings. The open-air beauty of the northern Rockies does not remove the risk inside enclosed sleeping quarters.

As in other western states, the main culprit is the deer mouse. It thrives in barns, sheds, and rustic lodging where food, warmth, and hiding spaces are easy to find. Even one or two mice can leave enough waste to create a hazard in a poorly ventilated room.

Before unloading gear, travelers should inspect kitchenettes, mattress seams, and corners for droppings. Keep snacks in hard-sided containers and do not leave backpacks full of food on floors overnight. If you are camping, choose sites with good trash control and avoid storing food inside sleeping tents.

Rural Utah Campgrounds and Slot Canyon Base Areas

Utah’s desert recreation hubs draw huge numbers of campers, climbers, and van travelers every year. While hantavirus is uncommon, state health guidance has warned that rodent exposure can occur in camps, sheds, pit toilet areas, and little-used storage structures, especially in dry regions where mice move close to human food and shelter.

Popular base areas near canyon country often combine exactly the conditions experts worry about: dusty enclosed spaces, food scraps, and lots of overnight gear. Travelers cleaning out vans, trailers, or camp boxes after long storage periods should be especially careful.

Officials advise against sleeping in buildings or storage rooms not meant for lodging. Air out enclosed vehicles and campers before sweeping them. Wipe surfaces instead of stirring up dust, and seal cereals, trail mix, and pet food in rodent-proof containers to reduce the chance of attracting mice.

Wyoming and the Greater Yellowstone Area

Wyoming has recorded hantavirus cases over time, and health officials in the state have long warned that cabins, sheds, and seasonal housing in cooler mountain regions can become exposure sites. That includes areas around the Greater Yellowstone ecosystem, where wildlife-rich surroundings also support healthy rodent populations.

For most park visitors, hiking and sightseeing are not the issue. The bigger concern is staying in rustic lodging or opening buildings that have sat empty through snow season. Rodent contamination can build up quietly in cupboards, utility rooms, and stored bedding.

Travelers should avoid handling dead rodents directly and should notify property staff if they find one. Bedding stored in garages or sheds should be checked outdoors, not shaken inside. If you own or borrow a camper, inspect vents and storage compartments before the trip begins.

Texas Hill Country and West Texas Parks

Texas is not the first state many travelers associate with hantavirus, but cases have been reported there, including in western and rural parts of the state. Health experts say exposure can happen anywhere infected rodents live, making cabins, hunting camps, and park shelters in dry regions worth extra caution.

In Hill Country and West Texas, spring travelers often reopen ranch buildings, trailers, and bunkhouses after long quiet periods. That timing can increase exposure risk because rodents may have spent weeks nesting in mattresses, drawers, and paper goods.

Before settling in, ventilate the building and inspect sleeping and food-prep areas closely. Use gloves for any cleanup, disinfect first, and wash hands thoroughly afterward. If someone develops fever, muscle aches, chills, or shortness of breath after a trip with heavy rodent exposure, doctors say they should seek medical care quickly and mention that exposure history.