A second tourist who had been visiting California's Yosemite National Park has been diagnosed with plague, California officials said Tuesday.
They said the patient, a visitor from Georgia, got tested after hearing that parts of the park had been closed to spray pesticides to kill fleas that carry the infection.
One popular campground was closed last week, and another is closed this week to spray for fleas after a Los Angeles girl came down with plague after visiting there and two dead squirrels were found to have been infected.
Related: Girl being treated for plague after trip to Yosemite
"Warnings issued in California regarding plague were useful all the way across the country in Georgia," state Health Officer Dr. Karen Smith said in a statement.
"Those warnings helped the patient get the prompt medical attention necessary to recover from this illness."
Plague can look like the flu and it can turn into a deadly illness if not treated promptly with antibiotics. Symptoms include a sudden fever, a severe headache, nausea and chills.
"Prior to becoming ill, the patient had been vacationing in Yosemite National Park (Yosemite), the Sierra National Forest and surrounding areas in California in early August," California's health department said in a statement.
"Although the presence of plague has been confirmed in wild rodents over the past two weeks at Crane Flat and Tuolumne Meadows campgrounds in Yosemite, the risk to human health remains low. Action to protect human and wildlife health by closing and treating campgrounds was taken out of an abundance of caution."
Plague infections in people are very rare in the U.S., with an average of seven cases a year, the Centers for Disease Control and Prevention says.
Earlier this month, Colorado officials said an unidentified adult died from plague. A 16-year-old Colorado boy died from plague in June after he developed an unusual and hard-to-treat septicemic infection. Two other Coloradans who caught plague this year were treated and recovered, including one whose dog is suspected of having carried the infection.
This story originally appeared on NBCNews.com