Smallpox vs. Chickenpox: What’s the Difference?

Smallpox vs. chickenpox: they’re both highly infectious, cause a rash, and have “pox” in their names. But they’re actually two completely different illnesses.

Smallpox was a severe disease, but you don’t have to worry about catching it anymore. Thanks to a massive global vaccination program, it was effectively wiped out in the 1970s.

Chickenpox is still around today. It’s less common than it used to be, though, thanks to another effective vaccine. And although it can affect certain people more severely, it is a much milder illness.

Read on for a closer look at the differences between smallpox and chickenpox. 🤒

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Smallpox vs. chickenpox

Smallpox used to be a big problem in the world. It existed for about 3,000 years and caused millions of deaths. Once a vaccine against it was developed, there was a huge global drive to wipe out the disease. And it worked: the last known natural case of smallpox was in 1977. And the World Health Organization (WHO) declared the disease eradicated in 1980.

Chickenpox is a milder illness that mainly affects children. And unfortunately, it is still around. The good news is that these days, most kids in the US are vaccinated against it, so chickenpox outbreaks are becoming less common.

And there are other ways that smallpox and chickenpox are different. Let’s take a look.

1. Smallpox was more serious than chickenpox.

Smallpox was caused by the variola virus. Its symptoms were similar to chickenpox symptoms—a rash, blisters, a fever, and other flu-like symptoms. But the difference was that the illness was much more severe.

About 3 out of 10 people who got smallpox died. Those who survived often had permanent scars, and some became blind.

Chickenpox is caused by a different virus called varicella. Most people who catch it will fully recover in one to two weeks. But while that may provide some comfort, it doesn’t make the itchiness any more fun.

2. Smallpox and chickenpox rashes look different.

Smallpox sores would appear all over the body at the same time, and they all looked very similar. The sores developed into fluid-filled blisters with a dent in the center before scabbing. These sores were mainly on the arms, legs, and face. But sometimes, they appeared on the palms of the hands or soles of the feet.

Chickenpox sores pop up on different parts of your body at different times. So while red bumps are just coming up in some areas, blisters are already scabbing over and healing in others.

Also, you mainly get the sores on your belly, chest, and back — not usually on your palms or soles.

3. There are different vaccines to prevent smallpox and chickenpox.

An effective vaccination program meant that we could get rid of smallpox a few decades ago. People rarely get vaccinated against it now, though, because there’s no one to catch the illness from! In the entire world, there are just two remaining samples of the smallpox virus kept in two different secure labs.

So it’s only really research scientists and military personnel working with or near these samples who might get the smallpox vaccine. And don’t worry: in the unlikely event that the virus should “escape” out into the world again, the US has enough smallpox vaccine stockpiled to protect everyone in the country.

With chickenpox, though, it is recommended that kids get vaccinated. While the illness is mild for most children, it can cause more serious problems for young babies, some adults, and people with weaker immune systems.

Vaccination helps to reduce the risk of vulnerable people becoming infected with the virus. The first dose of the vaccine is usually given when your child is one year old. They'll then get a booster between ages four and six. It’s very safe and over 90% effective.

What to do if your child catches chickenpox

If your child does catch chickenpox, the best thing to do is to keep them home from school or kindergarten until they feel better. That will help prevent the illness from spreading to other people.

There are also a few things you can do to help your child feel more comfortable while they fight off the chickenpox infection:

• Make sure they rest and get plenty of fluids. If it’s a challenge to get liquids down, popsicles also work.
• Keep them cool. Wearing loose clothing can help.
• Place a cool, damp cloth on their rash.
• Trim their fingernails, so it’s harder for them to scratch the rash. Putting socks on their hands can work too. 😊
• Give them a cool bath or shower each day and pat them dry with a towel. Try not to rub the spots as this may aggravate them.
• Try giving them over-the-counter antihistamines — oral or lotion-based — to ease the itching. Ask your pharmacist which type would be best.
• Use acetaminophen for pain relief. Aspirin isn’t safe for kids who have viral infections, as there’s a link between the drug and a serious condition called Reye’s syndrome.

Once all the chickenpox sores have scabbed over, they won’t be contagious anymore, so it’s safe to go back to school. That’s usually about seven to 10 days after the rash first appeared.

Important: If your newborn (under three months old) catches chickenpox, let your healthcare provider know right away. The illness can be more severe for newborns than for older kids.

Which is worse: chickenpox or smallpox?

In days gone by, smallpox was definitely a major health risk. But thanks to the global vaccination drive in the 60s and 70s, it’s not something we need to worry about catching anymore.

While chickenpox is a mild illness for most kids, it can affect some people more severely. For that reason, medical professionals recommend that kids get vaccinated against it. But if your child does catch chickenpox, you can do plenty at home to make them more comfortable as they recover.

We hope your little one is back to their usual, happy, itch-free self very soon! 🤗