YOSEMITE -- Two more Yosemite National Park visitors have been found to have a rodent-borne virus blamed for the deaths of two people, bringing the total number of infections to six, state health officials reported late Thursday.
Anita Gore, a spokeswoman for the California Department of Public Health, said the two new cases surfaced during the investigation into the outbreak of hantavirus pulmonary syndrome at the popular Sierra Nevada park.
The infections spurred park officials to close all 91 "signature tent cabins" at Curry Village. However, Gore said one of the cases may have originated in another area of the park.
Over the past three weeks, two people have died of hantavirus pulmonary syndrome after staying in cabins at Curry Village in Yosemite Valley.
Officials have sent warning letters to the roughly 2,900 people who stayed in the luxury tent cabins in Curry Village between June 10 and Aug. 24, notifying them of potential exposure of the rare but dangerous disease.
Over last weekend, a major cleanup effort was launched at Curry Village, including dismantling the cabins' unique hard-sided walls.
During the cleanup, park staff found holes chewed into the foam insulation of the cabins. A further investigation revealed several mouse nests and other evidence of rodents embedded in the walls, said Danielle Buttke, a park service public health official.
As cleaning and maintenance was completed on each cabin, visitors were allowed to move back in. However, on Tuesday, park officials reconsidered the decision and closed the cabins until further notice.
Short notice to move
Liz Varga and her family stayed in a tent cabin Monday, but the next night, they returned from a hike to find they had to move.
"We got back in the dark with our headlamps on and there was a note on our cabin saying, 'We have to move you,' " she said.
Varga, a Massachusetts resident who booked her reservations in April, said she called the park after hearing the news about hantavirus, but park officials assured her the cabin was safe.
"If I had known that it would have risen to that level and that there would have been a second death, then I certainly would not have stayed there at all, and I would have stayed in a different location."
The hantavirus outbreak occurred despite efforts by park officials to step up protection efforts in April. A 2010 report from the California Department of Public Health warned park officials that rodent inspection efforts should be increased after a visitor to the Tuolumne Meadows area of the park fell ill.
Officials say the luxury tent cabins were safe to stay in after last weekend's cleaning, but decided to close all of them because of the challenges of keeping the cabins rodent-free in the future.
Hantavirus -- a lung disease with flulike symptoms -- was linked to the park two weeks ago when officials confirmed that two people, one who died, likely contracted the illness after visiting in June.
Concerns increased earlier this week after a second death and a possible fourth case were linked to the same collection of cabins. Then two more cases were reported Thursday.
However, while Curry Village is reported to have several canceled reservations, many people continued to file into the park Thursday during the run-up to Labor Day weekend.
"It's about as scary as a lightning strike," said Greg Cizek, who drove up with his wife from Santa Ana to stay in the park's regular tent cabins. "I don't worry about it. It would never deter me from going anywhere. I think it's kind of overblown, actually."
John Bernal recently stayed in the regular tent cabins on his way to a motorcycle club event near Huntington Lake in the Sierra east of Fresno.
While he questioned the professionalism of the concessionaire who's responsible for operating and cleaning the cabins in Curry Village, he said he didn't have any immediate concerns about staying there.
"The hantavirus is all over the Sierra, so no matter where you go in the Sierra, you should be alert and aware. My understanding is that they went through and did a total sterilization of these units."
Mike Gauthier, Yosemite chief of staff, said the design of the luxury cabins, which are new to the park, allowed for rodent infestation. "We just weren't aware that design would lead to it," he said.
In 2009, the park installed the 91 new, higher-end tent cabins to replace some that had been closed or damaged after parts of Curry Village, which sits below the 3,000-foot Glacier Point promontory, were determined to be in a rock-fall hazard zone. The new cabins have canvas exteriors and drywall or plywood inside, with insulation in between.
The state concurs that officials in Yosemite took steps to deal with potential hantavirus exposure, but there are limitations, given the location.
"Yosemite, to their credit, has taken quite a few steps to address this," Vicki Kramer, chief of the state health department's vector-borne disease section, said. "But it's a wilderness area and these buildings aren't going to be tight. It's impossible to get rid of the deer mice, so there is going to be some risk to being in a wilderness area."
The Associated Press contributed to this report.
Reporter Joshua Emerson Smith can be reached at (209) 385-2486 or email@example.com.