Don’t Get Too Panicked About the Plague in Yosemite

In On the Trail, Tips, Travel

There’s been a lot in the media in the last few weeks about the plague in California. Believe it or not, the plague occurs regularly in California (yes, Yosemite is in California) and the western United States (especially Colorado, New Mexico, Arizona and California) with people getting infected every year. With proper treatment and medicine, most plague cases today are nonfatal. Here’s some information and tips about the plague and how you and your family can stay safe if you visit the park.

Plague cases in the United StatesPlague cases in the United States 1970-2012. The Illinois outbreak was associated with a research lab. Courtesy of CDC.

The Facts

From 1900 to 2012 there have been 1006 confirmed or probable human plague cases in the United States. Over 80% of plague cases in the United States have been the bubonic plague. In recent decades, an average of seven human plague cases have been reported each year (range: 1–17 cases per year). Plague has occurred in people of all ages (infants up to age 96), though 50% of cases occur in people ages 12–45 especially men and may be related to increased outdoor activities in men. (CDC)

Human plague reported cases and deaths in the United States 2000-2014. Courtesy of Courtesy of CDC.

Bubonic Plague

Bubonic plague is the most common form of plague. It usually occurs after the bite of an infected flea. The key feature of bubonic plague is a swollen, painful lymph node, usually in the groin, armpit or neck. Other symptoms include fever, chills, headache, and extreme exhaustion. A person usually becomes ill with bubonic plague 1 to 6 days after being infected. If not treated early, the bacteria can spread to other parts of the body and cause Septicemic or Pneumonic Plague.

Septicemic Plague
Septicemic Plague occurs when plague bacteria multiply in the bloodstream. Symptoms include high fever, exhaustion, light-headedness, and abdominal pain. Septicemic plague can quickly cause shock and organ failure.

Pneumonic Plague
Pneumonic plague occurs when plague bacteria infect the lungs. Symptoms include high fever, chills, cough,
difficulty breathing, and coughing up bloody mucus. Pneumonic plague is almost always fatal if not treated rapidly


So how do you avoid getting the plague?

That part is pretty easy.

  1. *DON’T PET THE ANIMALS.* This is something I have said time and time again on this blog. The animals in Yosemite are NOT tame. They are wild. They were not put there for your enjoyment. This is their home. They live there. They have fleas. Fleas carry the plague. If you try to touch or feed an animal, you put yourself at risk.
  2. Backwoods 101, never pitch your tent on or near animal burrows. Not only is the ground soft, unstable, and makes for a bad nights sleep, but the animals move in and out leaving fleas behind. If they can’t get in and out of their burrow because you’re blocking the entrance they may decide your backpack or clothing makes a softer bed than their den.
  3. Don’t leave backpacks and clothing outside. Put them in your tent, car, or if you have had food in them, in the bear storage locker at all times.
  4. Be wary of chew marks, new holes, or animals in your gear. Mice LOVE to get into your gear and will chew a hole right though your 20,000,000 denier ripstop pack to get at food or smelly items. Especially right now with the drought when food sources are scarce.
  5. Beware of brush, rock piles, firewood piles and the obvious animal burrow. All are places where rodents (and rattlesnakes, why’d it have to be snakes?) like to frequent.
  6. Leave your pet at home. Dogs carry fleas and will pick up fleas from the infected animals and bring them home. Don’t take the risk, leave Fido at home no matter how much it pains you. There are worse things your pet may bring into your house other than the plague like Lyme Disease. If you don’t think Lyme disease is worse, talk to someone who has it.
  7. Use a good DEET based insect repellent. Not only do mosquitos and other biting, flying critters hate it, so do fleas.
  8. Never, ever, ever touch a dead animal. Even with a stick. Fleas jump. They move. They will find the next food source even your arm. Report the dead animal in your campground immediately so it may be properly removed. And NEVER pitch your tent near where the dead animal was. People do stupid things, and can be very stubborn. I’ve seen it.
  9. Look for the warning signs. *NO REALLY*, the rangers post signs for things all over the park and in the surrounding national forests. READ. THEM. If there is a plague warning for a particular area, stay out.
  10. If you start showing signs after returning from a trip into a region where there is currently a plague outbreak, visit your physician immediately and TELL THEM you were in a high risk area so they can administer the proper blood tests and you can be treated. Stubbornness is the most prevalent cause of illness and death among humans.

For more information on the plague, symptoms and how to avoid it, check out this hand out from the Center for Disease Control.

You may also read!

Yosemite Open for Firefall but Reservations Required

If you're planning on visiting Yosemite to take in the world famous firefall over the next couple of weeks

half dome and yosemite chapel loyd schutte

Yosemite Closed

UPDATE: Yosemite National Park is open but reservations from are required to enter the park for ALL activities. Due


Glacier Point and Tioga Roads Close for Season

It's that time of year again when snow closes the Tioga Pass and Glacier Point roads. With the heavy


Mobile Sliding Menu