As if 2020 didn't have enough horrific disease, an oldie but baddie seems to be trying to make a comeback. A case of Yersinia pestis, or bubonic plague, has shown up in a patient in Northern China's Inner Mongolia. Though never fully eradicated, contemporary cases are very rare. Thanks to the discovery of antibiotics, this once devastating illness is not quite as scary as it was centuries ago when it was known as The Black Death, but it's still not to be trifled with.
Here's everything you ever wanted to know about the bubonic plague (and a few things you probably didn't), from the mortality rate to the toll the various plagues (yes, plural) took on the world.
What's the mortality rate of the bubonic plague?
While it's easy to feel like 2020 is the worst year on record in human history, we have a lot of things going for us in the 21st century, especially when it comes to public health. Before the discovery and mass-production of antibiotics, more than six out of 10 people who contracted the plague would die. It is an extremely deadly disease but, thankfully, one for which there is a cure.
That's not to say it isn't something to worry about. First, the availability of antibiotics can be quite low in some parts of the world, and because the plague is so rare, diagnosis may be slow. That said, the contemporary mortality rate for the plague appears to be between 8 and 10 percent, according to WHO, though that rate has been shown to be much higher in places where it is more common.
How do you get the plague? Is there a cure or treatment?
The bacteria that causes the plague is contracted either through fleas that carry the disease from rodents or through community spread from person to person. It can be spread through respiratory droplets or blood transmission. The disease has a relatively short incubation period of 1 to 6 days. There are three forms of disease brought about by Yersinia pestis: bubonic, septicemic, and pneumonic.
Bubonic plague affects the lymph nodes and usually comes from a flea bite. Untreated, it can spread to other systems of the body. Septicemic plague most commonly comes from a bite from an infected animal, but it can also develop from untreated bubonic plague. Along with symptoms like fever and chills, septicemic plague can cause necrosis. The last and most deadly form of plague is pneumatic, and it is the only version of the disease that can spread from respiratory droplets, making it the most contagious.
That said, risk of community spread of the plague is not as high as it was centuries ago. Though the plague pandemic known as The Black Death killed between 30 and 60 percent of Europeans, modern sanitation practices have significantly decreased the risk of community spread today. In addition to having antibiotics now, we also have sewers, indoor plumbing, and a much better understanding of hygiene, sanitation, and how diseases are spread.
Several hundred years ago, isolation of sick individuals was the only way to curb the spread and there was no treatment. There were several epidemics and pandemics associated with the disease throughout history, spanning four centuries. Nowadays, when someone is suspected of having the bubonic plague, which can be confirmed in laboratory testing, they are put in isolation and given a course of antibiotics even before tests come back.
Have there been cases of the bubonic plague in the U.S.?
Believe it or not, there are a couple cases of plague in the U.S. pretty much every year, According to the CDC, an average of seven human plague cases have been reported each year with a range of 1 to 17 cases per year in recent decades. It most often turns up in the Southwest in the warmer months of spring to fall.
Is there a vaccine for the bubonic plague?
According to the CDC, plague vaccines are in development but are not expected to be commercially available in the immediate future. Because the risk of transmission is relatively low and the death rate upon transmission is also fairly low, it is neither cost-effective nor practical to immunize people from the disease as we do for measles, tetanus, and other routine vaccinations.
So, in summation, while the words "bubonic plague" may seem scarier than the other health crises we face in the 21st century, you should be way more worried about SARS-CoV-2, the virus that causes COVID-19, than another Black Death.