But the plague isn't just something of the past.

It is still very much around and can still be deadly.

So maybe keep your plague.

Mass candy.

My wife and I were living in New York and the news was on, and she said to me, There's two cases of plague in Manhattan And of course, the first thing I said as an infectious disease.

Doctor Waas.

How cool is that?

Hi, my name's Larry Ludwig.

I'm a professor of medicine at the Mayo Clinic School for Medicine and Science.

My interest in plague comes from my work with the Program for Monitoring Emerging Diseases, which reports on and studies outbreaks throughout the world.

Now, when we're talking about plague, we're not just talking about one thing.

There are actually three major types of plague, depending on what part of the body is affected, except to see Mick, pneumonic and bubonic, which is what we think of when we hear the plague.

Since it's the most common type, what is commonly called plague, is an infection of animals and humans with a bacterium called your sin E a pestis.

This bacterium mainly lives in small rodents, but it can make the jump from animals to humans, making it a zoonotic bacteria.

Now there's usually a vector host and, in the case of the bubonic plague, its the flea.

Most of the time, a person was infected with play that infected through, ah, flea bite, where the flea tries toe feed on you and regurgitate some of the bacteria from the upper intestinal tract into the bite site.

Then the organism starts to replicate and spread through the local lymphatic system into the lymph plan.

Once they're the bacteria begin producing toxins to do two things.

They disrupt the body's regular inflammatory response and evade detection by defense cells called macrophages.

So now, with little standing in their way, the bacteria are able to multiply quickly in the lymph nodes with bubonic plague.

The classical manifestation is the boob Oh, which is an extremely tender, very large, swollen, boggy lymph node with readiness around it, And it said that if you have an individual who is sort of groggy or somewhat altered related to the infection just by pushing on the boob.

Oh, it's so tender that they tend to wake up and move around and, you know, yell at you.

But if you do come across someone with a boob, Oh, please don't try this.

Other symptoms may include fever, chills, body aches, nausea and vomiting, all of which can usually take anywhere between one and seven days to pop up.

But probably the most important thing to keep in mind is the timing here is crucial because things can go downhill quickly if treatment isn't started immediately.

And that goes for all three types of plague.

If treatment for bubonic plague doesn't work or is administered too late, or if the bubonic stage doesn't occur, then the bacteria can continue it spread from the lymph nodes into the bloodstream, where it starts to multiply.

Called step to see Mick Plague.

This is a much more serious infection where patients can Philip shock bleeding into the skin, and, most recognizably, the skin can turn dark and die.

And that's presumably what the black Death waas, the SEPTA Simic phase of the illness.

And then there's pneumonic plague, which is the most dangerous out of the three, where the bacteria has spread into the lungs.

It's the rarest form of plague.

But unlike bubonic and SEPTA, Simic pneumonic plague adds a wildcard human to human transmission, with the bacteria spreading via infectious respiratory droplets.

And because of its potential as a biological weapon, the plague is a category, a pathogen in the U.

S.

It's not going to go away because it's endemic in an animal population.

That's one of the reasons why we were able to eradicate smallpox because smallpox was not a zoo in oh, sis, we were able to immunize around it and eradicate diseases that are zoo in oh, sis pose a particularly difficult problem in eradicating.

But the good news is that we're no longer in the 14th century, and we've got plenty of antibiotics to treat plague, which usually seem to do the trick.

Currently, fewer than a dozen cases pop up in the US on average every year.

On between one and 3000 cases are reported around the world.

There have been vaccines.

There was, ah, killed plague vaccine that was used in the military through the Vietnam War.

It's no longer really used.

There are some other vaccines that are undergoing studies in various parts of the world, but currently there is not a licensed Blake vaccine in the United States.

It's difficulty to get adequate funding to produce good, safe, effective vaccines for diseases that don't really affect the developed countries.