Another person has been sickened by hantavirus originating in Yosemite National Park, the ninth case in a rash of the rodent-borne disease that has killed three visitors since mid-June.
The latest case sickened a California resident who stayed in a Curry Village "signature tent cabin" in early July, park spokesman Scott Gediman said. The person has since recovered, he added.
But the latest case was a milder infection, with flulike symptoms that did not advance to hantavirus pulmonary syndrome, the respiratory ailment that can prove fatal, according to park and health officials.
Officials have called the Yosemite outbreak unprecedented — more than one hantavirus infection from the same location in the same year is very rare. The disease is typically transmitted to humans when they inhale dust or dirt containing the droppings or urine of infected mice.
News of the ninth case came as Yosemite officials began yet another wave of public notifications, this time emailing some 230,000 people who reserved lodging throughout the park since early June.
Officials have already sent emails and letters to about 3,100 people who reserved one of the 91 signature tent cabins, where all but one of the cases were believed to have originated. Thousands of additional notifications went out last week after another case was traced to the High Sierra Loop, the link between Yosemite Valley and Tuolumne Meadows and other areas.
But some recent visitors have complained about what they consider a dearth of information from the park. Park officials have said they focused initial outreach efforts on those believed to be most at risk.
"We heard some concerns from visitors, and people read about it in the media, so we felt that we wanted to be proactive and transparent and get the word out to additional overnight visitors," Gediman said. "We want to get out all the information we can."
The letter says there is "no evidence at this time" to indicate that people who stayed outside the signature tent cabins and High Sierra camps had an increased risk of exposure.
"Nevertheless, we want to ensure that all our guests have accurate and current information on hantavirus," the letter read.
The signature tent cabins have been closed indefinitely as an investigation into the outbreak continues. The High Sierra camps close for the season next week.
Public health authorities have trapped and tested deer mice as part of their investigation and said a larger-than-normal population could be a contributing factor.