No Plan for Plague

No Plan for Plague

Bubonic plague. The Black Death of the Middle Ages. No, it wasn’t a one-hit wonder. It’s still around.

Shortly after moving to Colorado from the eastern United States, I was surprised to see an article in The Gazette about squirrels and ground squirrels being confirmed to have died of plague on the west side of Colorado Springs. This was a joke, right? The plague went out with the middle ages…didn’t it? No, it didn’t. And the article was no joke. Yersinia pestis, the bacterium that causes the deadly disease, is alive and well in the western United States, as well as in other parts of the world.

The World Health Organization has a succinct description of the plague and why you should care about it:

“Plague is an infectious disease caused by the bacteria Yersinia pestis, a zoonotic bacteria, usually found in small mammals and their fleas. It is transmitted between animals from their fleas. Humans can be contaminated by the bite of infected fleas, through direct contact with infected materials or by inhalation. Plague can be a very severe disease in people, particularly in its septicaemic and pneumonic forms, with a case-fatality ratio of 30%-100% if left untreated.” (, WHO 2018.)

As mentioned, it’s not just a “bubonic” plague — there’s more to it than that. The plague is a zoonotic disease (passing between humans and animals) caused by Yersinia pestis bacteria, and comes in three forms:

(1) Bubonic, the mildest, most treatable, and least fatal of the three forms causes bumps or “buboes” in the regions of the lymph nodes.

(2) Septicemic is a more serious form than bubonic, in which the infection has spread to the bloodstream.

(3) Pneumonic, which affects the respiratory system, is easily transmissible through the air, and has the highest mortality rate (80 – 100%) of the three.

Any given outbreak of “bubonic plague” is not limited to the bubonic form. Yersinia pestis can occur in any and all forms simultaneously in an outbreak. Even the bubonic form can be spread not just by flea bites, but also by contact with fluids or tissues of an infected animal. A coyote could contract the plague by eating an infected prairie dog. Your dog could contract the plague from eating an infected rat, and spread it to you either via flea bites, or by sneezing in your face. There’s speculation now that the plague of the middle ages was as devastating as it was because it had become pneumonic.

Knowing that the bubonic plague had wiped out a third to half (or more) of the population where it spread in the middle ages, I vowed to avoid wild rodents, and otherwise didn’t give it a lot of thought.

Several years later, I purchased land out on the prairie some distance east of Colorado Springs, where I eventually built and moved into a house. A couple years later, I began to notice prairie dogs spreading across miles of prairie whereas previously there had been none, the closest having been a one square mile colony twenty miles away. After a few years of increasingly dense prairie dog infestations, including on my own and my neighbors’ properties, I found a stack of Health Department notices that a property owner had copied from the postings on their land and had left as a public service announcement in the local post office. That was the summer of 2014.

Bubonic Plague in eastern Colorado
Health Department confirmation of Plague in El Paso County, Colorado

I called the county health department, and spoke with a gentleman who informed me that the plague and tularemia had been confirmed in rodents (rabbits and prairie dogs) in the Yoder area, and the diseases seemed to be spreading from there toward the northeast. My direction. He told me to watch out for the signs of a plague die-off in the prairie dogs.

“What are the signs?” I asked.

Three things, he told me:

  1. The smell of death
  2. Vultures (buzzards)
  3. Cobwebs across the prairie dog holes

I had contacted the soil conservation district when the prairie dogs began to invade my fields and the neighboring pastures, to see if the government agencies had an eradication plan and assistance. No. They were doing nothing. Now, the man at the health department told me they were doing nothing about the prairie dogs, and nothing about the plague.

“We used to have a program of applying pesticides during the plague die-offs, but we stopped in 2008 when the financial crisis hit and we no longer had the funds,” he told me.

I wasn’t sure if the pesticides had been for the prairie dogs (and other rodents) or for the fleas. It didn’t really matter at that point, since the pesticides no longer were available. He’d told me the plague is endemic in prairie dog colonies, and periodically there will be die-offs.

He also told me that as the host rodents die, the infected fleas will hang around the mouth of the prairie dog holes, waiting for a mammal to walk by close enough for them to jump on. He told me to stay away from the holes. By this time there were so many prairie dogs and so many holes, this prevented me from walking over to the other side of my property. Fortunately, there was sufficient rain that summer (and the next) that I didn’t need to walk over to that side to water the few trees and shrubs I’d planted there. But when the neighbor’s bull and a cow jumped over the fence, they just spent the summer, as it wasn’t safe to go out with the dogs to chase them home.

Cattle and horses are not known to contract plague. Mine were out to pasture during the prairie dog die-off there, and were fine. However, in Colorado Springs a mule deer had been confirmed to have the plague. This seems to leave the susceptibility of hoofed animals somewhat in question.

Within a few months of finding the notice in the post office, I noticed a decline in prairie dog activity, beginning at the southwest corner of the property. I’d see up to four hawks at a time standing on the ground around the property’s fringes, scavenging. This photo was taken October 17, 2014.

Hawk scavenging prairie dogs
Hawk scavenging

Sometimes there was a buzzard. Evidently the hawks and buzzards were eating dead prairie dogs, though from across the field, I wasn’t able to confirm what was lying on the ground. It was in the vicinity of the prairie dog burrows at the time the prairie dogs ceased to be active there. Presumably, they had died and were being eaten by hawks and buzzards.

Buzzard attracted by plague-killed prairie dogs
Buzzard taking flight

A subsequent voicemail I left with the health department went unanswered. Another call, in which I was feeling more frantic as the die-off worked its way up the hill and closer to my buildings, I was told that there was no reason for the health department to get involved, “because the mortality rate of bubonic plague is only 11%.” That was the mortality rate given by the literature at the time for the bubonic form of the disease, when treated quickly with antibiotics. WHO now says there’s a 15% case-mortality if promptly diagnosed and treated. But plague often isn’t diagnosed quickly. Doctors usually aren’t looking for a plague diagnosis. The septicemic rate of mortality is much higher, and the pneumonic rate approaches 100%. This is another case, in my mind, of human “it can’t happen here” ignorance and arrogance, coupled with a tendency toward inertia.

At some point, I had a conversation with someone from the Centers for Disease Control and Prevention (CDC), in which we discussed the two types of mice in the vicinity of my house, barn, and chicken houses. The plain grayish-brown ones in the barn and chicken houses that I had thought of as “field mice” I was told were “house mice” and that they were less likely to carry the plague than the deer mice that occasionally were found in the house or car. I was warned that cats are very susceptible to plague, and treated mine with Revolution, obtained from their veterinarian.

The barn was the building closest to the die-off. Next were the chicken houses. Then the driveway, and the house. The die-off was getting closer and closer to the barn — about a hundred feet. Times were stressful.

The beginning of the second week of November, I was out doing chores one afternoon, and noticed a speck on the sleeve of my denim shirt. I thought it was one of a tiny ubiquitous bug, and went about my business. When I finished my task, I noticed the bug was still there. I looked at it closely, and realized it was not one of the tiny beetle-type bugs I’d thought, but rather a flea. Since it’s not in a flea’s nature to sit quietly on one’s sleeve during a prolonged period of physical activity, I believed it had to be ill. I believed it had the plague. When the fleas get sick with plague, the bacteria clog their digestive tracts, and they’re not able to eat properly. This one was decidedly sluggish. I was wearing work gloves, and caught and squashed the flea using a gloved hand, before removing the glove, never to be worn again.

I made a trip to town for rodent “bait” and for insecticides, as well as materials for chicken-safe rodent traps.

Finally, in late November, we had an unusual very early, very hard freeze that extended over a period of days. Normally this type of freeze occurred later, in December. This year it was just in time, because the die-off had reached within a hundred feet of the barn. After the freeze, I didn’t have to worry so much about loose fleas, but I still had to try to keep the cats and dogs free of fleas.

By the end of winter, I thought all the prairie dogs on the property had died, but in the spring of 2015, I noticed a couple more digging new holes a few hundred feet south of the barn. Over several weeks I noticed up to four out scampering around all at once, but they disappeared by the end of the summer, and I haven’t seen them since. That, too, was a wet year, and I was again thankful I didn’t have to venture across the pasture to the other side of the property, though at one point my neighbor and I drove out in their pickup truck to deal with their cattle and mend fence. I wonder if Yersinia pestis is still out there waiting for a new batch of prairie dogs, or if it, too, dies out, and returns only with the rodents.

World Health Organization

The World Health Organization has a plan for fighting plague, acknowledges that the pneumonic version of plague has a 100% case-mortality rate when untreated (and not much better when treated early), and is actively working to eradicate plague from places such as Madagascar.

WHO Plague Fact Sheet (WHO | Plague)


Fact sheet
Updated October 2017

Key facts

  • Plague is caused by the bacteria Yersinia pestis, a zoonotic bacteria usually found in small mammals and their fleas.
  • People infected with  pestis often develop symptoms after an incubation period of one to seven days.
  • There are two main clinical forms of plague infection: bubonic and pneumonic. Bubonic plague is the most common form and is characterized by painful swollen lymph nodes or ‘buboes’.
  • Plague is transmitted between animals and humans by the bite of infected fleas, direct contact with infected tissues, and inhalation of infected respiratory droplets.
  • Plague can be a very severe disease in people, with a case-fatality ratio of 30% to 60% for the bubonic type, and is always fatal for the pneumonic kind when left untreated.
  • Antibiotic treatment is effective against plague bacteria, so early diagnosis and early treatment can save lives.
  • From 2010 to 2015 there were 3248 cases reported worldwide, including 584 deaths.
  • Currently, the three most endemic countries are the Democratic Republic of the Congo, Madagascar, and Peru.

State of California

California has a plan for plague, and has published the California Plague Compendium, a (currently) twenty-eight page document that includes not only information about plague-causing Yersinia pestis bacteria and its vectors, but also, “response plans that include not only detection and treatment of immediately affected human victims but also outline vector and rodent control measures….” (p. 9, California Compendium of Plague Control, Sept. 2016,

El Paso County

El Paso County, Colorado has…well…a brief mention not easily found on their County Health Department website, but a .pdf is available if you search specifically for “bubonic plague”. The article includes this:

“What are the signs and symptoms?
Typical symptoms include sudden fever and chills severe headache, muscle aches, nausea, vomiting and a vague feeling of illness. A common symptom of plague is swollen lymph nodes. (The swollen painful node is called a “bubo.”) Other forms of the disease include septicemic illness with no bubo developing, and pneumonic plague in which the lungs are involved. The septicemic and pneumonic forms are the most serious.”

What that fails to mention is that the pneumonic form of the plague is 100% fatal if untreated (80% fatal if treated early), and can be spread through the air. It also fails to mention that one type of infection can become another – that is, bubonic plague spread by a flea bite can become pneumonic in the victim, and thereafter spread to others through the air as well as by further flea bites.

Beyond that, nothing. No plan for plague. When you tell them you have a plague die-off on your property, what do they do to help? Nothing. When asked, “Why not?” The response: “Bubonic plague only has an 11% mortality rate.” And that’s acceptable? Furthermore, that’s when diagnosed and treated early — which it often isn’t. And when it isn’t, it’s a 30 – 60% mortality rate. And again — bubonic plague can become pneumonic plague in the blink of an eye, be passed between man and beast through the air, and approach a 100% mortality rate.

If that happens, what will you do then? Nothing? Or then will it be too late? El Paso County, Colorado has no plan for plague.