Why did the smallpox vaccine application leave such a prominent scar?

And how come no other vaccines did the same?

The vaccination was given intradermally (i.e., barely under the surface of the skin), in a cluster of pinpricks, and created a rather large pustule at the site, which was the body’s response (hence the meaning of the name “smallpox.”) Tuberculosis vaccinations also sometimes leave scars.

The actual size of the scar depended on the person’s normal reaction to scarring. E.g., I have a barely noticeable scar while my daughter has a really nasty one. But every scar my daughter gets is really nasty.

I had a smallpox vaccination about 60 years ago, but the scar is no longer visible.

Interesting, because I scar very easily but my smallpox one is also barely visible.

It is my understanding that, at least initially, the smallpox vaccine actually gave the person another closely related disease, cowpox. The story goes that Jenner noticed that dairy workers rarely got smallpox, having contracted cowpox from the cattle. Cowpox gave you one pustule plus immunity to further infections of either cowpox or smallpox. Imagine how nasty it would be to have those pustules all over, plus the scars if you survived.

My scar migrated up to my shoulder and is barely noticeable. I forget it’s there often. Most people get the vaccination at a young age and the results vary depending on how the skin grows. I’ve seen some that stretch out over a large area, and others like mine just move to someplace else and stay small. I don’t know why they choose the arm other than it being readily accessible. Maybe there’s someplace where it’s likely to stay in place and not grow along with your skin.

The BCG (tuberculin vaccine) leaves a prominent scar. I had it as a babe so I don’t have a scar but my brother got it as a teen (like most British kids in those days and I think still) and has a large set of scars on his right shoulder. Big one in the middle, a ring of smaller ones around the outside.

All this just leads us to the more fundamental question: Why is the smallpox vaccination delivered the way it is, and not in a similar manner as nearly all other vaccinations?

Just as a matter of historical accuracy:

The inoculation of people with cowpox was a well known folk remedy among rural people for hundreds of years, if not longer, before Jenner became involved.

He became aware of this folk remedy as a consequence of discussions he had with some farmers. He gained credit for it as a result of his promoting the process among the aristocracy. His status as a “gentleman” gave it credibility that it lacked when presented by a mere peasant.

So, contrary to popular belief, he was not its discoverer; he was only its promoter.

This specific topic was covered in a course on infectious diseases for non doctors I took about forty years ago; while I have no cite, I am confident my memory is accurate and sound.

Agreed. It was on my right upper arm. Scar is gone. Didn’t notice until this post. Thanks.

Can leave a prominent scar. I got it as a teen, and I have no scar.

The smallpox vaccine contained about 200 proteins, and so delivered a larger antigenic challenge compared to modern vaccines (all the routinely administered childhood vaccines put together contain fewer proteins than that thanks to advances in vaccine development).

This may be the reason smallpox vaccine used to cause a larger local reaction, and in some cases, scarring.

I stand corrected. Did you get it in the butt? I’ve heard it produces less scarring there.

I recall being examined by an doctor for a physical required for a job a long time ago and he rambled on throughout the physical about things like he could tell where someone was from or when they born due to the type of smallpox vaccine scar they had. Some counties did them on the calf while other did them on the arms and butts to name a few. Not sure if it was BS or if it was just something to distract me while he poked and prodded.

Upper arm. There was a lot of talk beforehand about how painful it was and how horrible it would be afterwards, but it varied a lot from person to person.

Yeah, I have two such scars (I had a BCG twice) on my left shoulder. So smallpox is not the only vaccine that leaves a scar.

Smallpox vaccination is actually an infection with vaccinia virus, a virus of obscure origin (presumably derived from some sort of animal pox virus) that can infect the skin, often causing scarring, but that also induces immunity to the smallpox virus.

The advantage of the live virus is that you you can tell if the inoculation caused infection (necessary for inducing protective immunity) by looking at the skin reaction. If there is no skin reaction, the person probably needs a second dose. Of course, live vaccines have their disadvantages as well.

I think the main reason a we used the smallpox vaccination method that we did was that it was the first method developed and it worked. Why change?

In the US, the vaccine was routinely applied to the upper arm. In Europe, I believe that it was routinely applied, as least to female children, at a location less often on view.

variola virus,

Mine is on the right side of my back, basically on my shoulder blade. I recall my Mom once saying something about the doctor asking where to give the vaccination and saying the arm would leave a more prominent scar than the back, so back it was. Not sure what your doctor would have said but this was in Texas in the early 60’s.

I got the smallpox vaccine just above my hip (Europe, probably early 1960s) and still have a slight scar.

Before reading this thread, I thought smallpox was wiped out in the 19th century (knowing about Edward Jenner and the furst vaccinations). Apparently smallpox vaccinations were routine until the 1970s.

Really not all that bright, routine BCG vaccinations for schoolchildren ended in 2005 (in the UK). They still give it to babies, and to children in “high risk” areas.