SciTech

Things that could kill us but hopefully won’t: smallpox

Content warning: smallpox

We’re back to one of my longest running fixations and greatest fears, folks: smallpox. I’m so afraid of it I don’t think I can even be funny about it, so we’ll just launch right in.

Smallpox is a terrifying disease which ran amok in the human population throughout the world for centuries. It is spread through airborne particles released when the infected breathes/coughs/etc., or even through the scabs which fall off of the actual pox marks themselves as the afflicted heals.

There are five different forms of smallpox: Variola minor, plus four different types of variola major — ordinary, modified, flat, and hemorrhagic. Variola minor is super chill. You get some mild rash, it’s really not severe, and death rates are below one percent. Variola major, however, is a different story. The ordinary form is most common, being responsible for about 90 percent of cases. About two weeks after exposure, you start with fever, malaise, and general achiness. Then, you start in with the maculopapular rash (which essentially looks like you’re breaking out in hives). The rash starts in your mouth and on your hands and forearms. It then spreads inward to your arms, legs, and body as the disease progresses. After a couple days of this stage, lesions called papules will start appearing, spreading in the same way as the initial rash. The papules will eventually progress to vesicles (basically blisters), to pustules (uglier, pus-filled blisters, like pimples). Finally, the lesions will scab, the scabs will fall off, and you’ll be rid of smallpox, and safe for the rest of your life — that is, if the smallpox didn’t kill you first by crippling your immune system.

Ordinary variola major has a mortality rate of about 30 percent, a little less than one in three. If you do manage to survive, congrats! You get to move on without fearing smallpox ever again — PSYCH!!!!!! Modified smallpox can still come back for you! The second form of variola major, modified smallpox exclusively occurs in people who have been infected with smallpox before, although it is a much milder form with a mortality rate less than one percent.

Flat smallpox, also known as malignant-type smallpox, starts out much the same as ordinary smallpox, but with a much longer pre-rash period. However, things start to get crazy once the rash forms. When an ordinary type case would usually turn to the vesicle stage, and the lesions would become raised bumps on the skin, flat smallpox stays flush. The rash also matures much slower in flat smallpox, and the pre-rash symptoms remain severe throughout the entire process. Lesions will often hemorrhage under the skin, and many will become confluent, meaning they’ll get so crowded up against one another that they merge from a bunch of small lesions into a few really huge ones. Flat smallpox usually affects children (in about 72 percent of cases), and has a 97 percent mortality rate.

The fifth and final version of variola major is the scariest of all. Hemorrhagic smallpox is truly the monster that is constantly going to be living under my bed. It starts off with high fever, intense headache, and abdominal pain. Then, skin will become dusky, with red erythema. This is quickly followed by petechiae (tiny spots of bleeding) under the skin, as well as in the eyes and mucous membranes. Luckily, most people die here (around the fifth or sixth day), before things get really bad. If they survive a few days longer, their skin detaches as fluid accumulates just beneath the surface in one huge confluous blister. It becomes very fragile and can tear at the slightest prodding, leaving large areas of rawness. Patients with hemorrhagic smallpox are usually conscious right up to the very end, and then they die. Hemorrhagic smallpox has a 100 percent mortality rate.

Are you scared yet? Perfect, me too. However, allow me to soothe you for a moment — we found a quite effective way to prevent smallpox way back in 1796, after a guy called Edward Jenner noticed that dairy maids who had been exposed to cowpox very rarely got smallpox! He infected his gardener’s kid with cowpox, and the rest was history. Despite having an effective vaccine, outbreaks were still quite common for a long time. However, after a long, hard battle, and many many successful case containments using ring vaccinations, smallpox was officially declared eradicated in 1980 by WHO!

Since humans are the only possible host for smallpox, this means that we are totally safe from ever having to worry about smallpox again, yippee! That is, of course, unless someone with stores of live virus decides to weaponize it… but that’s a fear for another article! Until then, you can sleep soundly knowing that you’ll never need to worry about centrifugal rashes or confluent hemorrhages, even if I won’t.