Yosemite, which was established in 1864, is no stranger to high-profile outbreaks of infectious disease.
In 2017, a Santa Monica middle school temporarily canceled classes after nearly 200 students were potentially exposed to norovirus there.
In 2012, a deadly hantavirus outbreak put Yosemite — the heart of the Sierra Nevada economy with 5 million visitors each year — in triage mode. Three people died and six more became ill after staying at Curry Village. The visitors who contracted hantavirus had inhaled large quantities of dust containing urine, saliva and fecal matter from infected deer mice.
About 170 visitors and employees to Yosemite Valley have fallen ill in recent weeks, prompting an investigation into the cause of a norovirus outbreak.
Source: Feds investigate causes of a norovirus outbreak at Yosemite National Park – Los Angeles Times