Outbreak report sluggish

Yosemite National Park and health officials knew of a rare rodent-borne illness several days before the public was notified of its probable connection to the Curry Village campground, and many later-closed park cabins continued to be rented for days, according to several sources.

Mariposa County Public Health Officer Dr. Charles Mosher said his agency and the California Department of Public Health became aware of a likely hantavirus fatality on Aug. 9. The report, shared with park officials the next day, helped solidify suspicions of a Curry Village-hantavirus connection raised in late July when another person became ill.

The two cases, however, weren’t reported to the public until Aug. 16.

“There was just a lot of discussion between the state and the park about the press release, whether it was the right time,” Mosher said of the delayed announcement.

Mosher said he didn’t want to “point fingers” about what took place in the discussion, but the California Department of Public Health ultimately decided to release information about the hantavirus cases on Aug. 16.

He added that before the press release was sent by the state health department, drafts were examined by himself, the National Park Service, state authorities and even federal public health officials.

The overall discussion about the release included the Park Service, the state health department and Yosemite’s lodging and food concessionaire DNC Parks & Resorts, he said. 

Yosemite National Park spokeswoman Kari Cobb said there was no delay between the park’s receipt of confirmation about the fatality and the Aug. 16 press release. She also said no time was spent on multiple drafts. 

“We wanted to put all the information out there and make sure everybody knows the whole story,” Cobb said. “We wanted to be as transparent as possible.” 

She confirmed that DNC was part of the process but said its role was routine.

“Of course we’ve been working with DNC on it,” she said. “We run a business with the concessionaire. We want to keep them in the loop with every step that we take.” 

The sickened

As of Thursday, six people who visited Yosemite from June through mid-July were reported to have become ill with hantavirus pulmonary syndrome, a rare disease spread by deer mice. Two visitors who stayed in the Curry Village “signature tent cabins” later died, one within hours of going to the hospital.

On overlapping days in mid-June, four Yosemite visitors likely contracted hantavirus while staying in the signature tent cabins at Curry Village, according to health officials. The first two hantavirus patients stayed in cabins within 100 feet of each other from June 10 to 13. 

Symptoms of hantavirus pulmonary syndrome typically don’t appear until one to six weeks after initial exposure to the virus. They begin with fever and aches, which can move on to severe difficulty breathing and symptoms similar to pneumonia or bronchitis.  

The first Yosemite-related case, a 49-year-old Southern California woman, became ill at the end of June. She went to the hospital on July 5, and her Los Angeles doctor contacted Mosher the next day after learning she had traveled to Mariposa County, where Yosemite Valley is located. 

A two-step test came back positive for hantavirus, and public health authorities traced possible sources — a process that led back to Curry Village by late July. The woman left the hospital on July 18 and is expected to survive.

The second hantavirus patient was a 36-year-old Bay Area man who died on July 31. A 45-year-old Pennsylvania man who had stayed at Curry Village later died on Aug. 12. His death was linked to hantavirus by the Pennsylvania Department of Health on Aug. 24.  

Yosemite National Park sent out a press release about the fatality and a possible fourth case the evening of Monday, Aug. 27. 

The fourth infected person, a 43-year-old Southern California man, was released from the hospital Aug. 2.

The infection of two other people was reported Thursday night (see related story).

Hantavirus pulmonary syndrome has fatality rates of more than 30 percent.

There is no cure for hantavirus pulmonary syndrome beyond what doctors describe as “supportive” treatment to help the patient’s immune system battle the infection. 

Notification

Yosemite spokesman Scott Gediman said the park became aware of a possible link between the first hantavirus case and Curry Village “at the end of July.” He also said he was not able to retrieve the exact date because of the volume of media inquiries he was receiving. 

 The California Department of Public Health and the Mariposa County Health Department traveled to Yosemite for an initial investigation, and to make public health recommendations about hantavirus, on Aug. 9. 

At that point, a call came in about a likely second hantavirus patient, Mosher said. The 36-year-old Alameda County man got sick about July 23 and died July 31, just 24 hours after going to the hospital. 

Mosher said tests had already come back positive for hantavirus, and possible connections made to Yosemite, on Aug. 10 — the day of a debriefing he attended. 

But it wasn’t until the Aug. 16 release that the apparent link between two hantavirus cases and Yosemite was mentioned to the public.  

A California Department of Public Health spokeswoman said she didn’t have specific details about the process that took place in Yosemite. But reporting protocol, and the need to confirm data with multiple agencies, may cause what appears to be a notification gap, she explained. 

“I think everybody wanted to be a bit more certain,” Mosher said. “Then the state kind of took the lead and said we really need a press release.

“There were some discussions and there were some different points of view about what was the best thing to do,” he elaborated. “Was it best to keep working on housekeeping and working on the tents, or should we all do a much broader release?” 

Gediman and Dr. Vicki Kramer, chief of the California Department of Public Health’s vector-borne diseases division, both said a press release was issued very quickly after the agencies received information about the first fatality.

“Literally the day we knew of the first two cases linked to Curry Village — that was on Aug. 16 — we sent out the news release,” Gediman said.

When asked whether the park should have notified the public that a hantavirus investigation was under way Aug. 9, Gediman compared the scenario to a safety inspection at a restaurant. 

Restaurants don’t usually close during the inspection process or announce an investigation is occurring, he said.

“We had to be very careful that all the t’s had to be crossed and the i’s had to be dotted,” he added. “We wanted to be sure.” 

Kramer said it is the state health department’s philosophy to notify the public of risk as soon as possible. 

“We actually notified the public fairly rapidly as soon as we learned of the second case,” Kramer said. “I think we were quite responsive in analyzing the situation and getting a press release out.” 

Until the health department learned of a second Curry Village-related case during its investigation, the first case wasn’t considered unusual, according to Kramer. 

Mosher said the decision about when to release information was ultimately out of his department’s hands. One factor considered was whether the most effective response would involve educating only the housekeeping staff so they could help prevent illness in guests. 

Cabin closures delayed

Delays in notification paralleled delays in closing affected cabins.

By Aug. 16, as state health officials were notifying the media about the hantavirus connection, the cabins where two guests had become ill had already been cleaned and re-rented.

This was confirmed through Cobb, who declined to give the cabin numbers that day so as not to disturb their guests.

By Aug. 28, the park was in the process of closing the 91 signature cabins so they could be “retrofitted” to keep out rodents, according to Gediman.

That night, as park concessionaire DNC was trying to contact guests who stayed in the Signature Tent Cabins from mid-June through the end of August, many of the signature cabins were still occupied, Gediman said. 

He added they were empty the following day, Aug. 29. 

The park did not move guests out of the cabins at once. Rather, DNC simply stopped taking new reservations, he said.

Mosher, contacted Aug. 29, was surprised and said he was under the impression the cabins had already been closed.

He got a call from someone who stayed in a Curry Village cabin who said that if he had known about the hantavirus risk, he would have chosen other lodging. 
“It’s clear that some people would have made the decision not to go” if they had been notified of the risk, Mosher said.

Notifications continue

As of Thursday afternoon, DNC had expanded the list of people it’s trying to contact about the hantavirus risk to 2,900 guests. It is tracking the number of emails opened and re-sending ones that aren’t, park officials said. Notifications are also being made by postal mail and phone. 

“I recognize that this notice may raise concerns on your part, but it is being sent in the interest of public health,” said the email notification signed by DNC Parks & Resorts at Yosemite president Dan Jensen. 

“If you or any member of your party has the symptoms described, please immediately seek the attention of a medical professional,” the note concluded.  

At 6 p.m. Thursday evening, the California Department of Public Health sent out another press release announcing additional confirmed hantavirus cases linked to Yosemite — bringing the number of people infected at Yosemite to six. 

Three patients have now recovered, and one patient is in the hospital but improving, the release said. One patient stayed in an “unspecified” part of Curry Village, and the other is under investigation. 

Earlier warnings

The recent concerns raised about hantavirus in Yosemite follow earlier warnings about the disease.

The California Department of Public Health issued a statewide hantavirus warning May 7 after it had been found in Riverside County mice, giving generalized tips about how to avoid infection.

In 2010, state health officials advised Yosemite officials to educate tent cabin guests about the disease after a 54-year-old woman who visited Tuolumne Meadows became ill.

California Watch reported Thursday that the warnings went unheeded.