Why Your Dad’s Vaccination Scar Is Still a Badge of Honor

For those born before the 1970s, that telltale round mark on the upper arm represents victory over a global crisis

All scars tell a story. Some of these stories are extraordinary, while others are of the “I fell out of my chair and busted open my chin on the table” variety, but each ends with our skin modified, our injured bodies forever altered. While most underlying scar stories are unique to the scar wearer, though, the vaccination-scar story — most notably, the classic smallpox vaccination scar, a pockmark on the skin that perfectly encapsulates humankind’s forever-war against the perils of nature — is shared human history.

Introduced in 1796 by English physician and scientist Edward Jenner, the smallpox vaccine was the first of its kind. “By inserting pus from a milkmaid with cowpox, a disease closely related to smallpox, into the arms of a healthy 8-year-old boy and then variolating him to no effect, Jenner was able to conclude that a person could be protected from smallpox without having to be directly exposed to it,” reports “This was the world’s first successful vaccine, a term that Jenner himself coined.” 

Despite the development of this original vaccine, smallpox would continue to kill hundreds of millions of people worldwide, including through much of the 20th century. In fact, for many years, the vaccine scar was seen as a way to prove you weren’t a threat to your family and community. “It was literally like wearing a vaccination record right on your arm,” historian Jennifer Keelan told

It wasn’t until the development of a heat-stable, freeze-dried vaccine (1963) and the bifurcated needle (1961) that made it possible to easily and effectively inoculate patients with the vaccine, that the disease was eradicated from the U.S., reports Appalachian magazine. This development explains why I (and indeed, almost no one else born after 1972 in the U.S.) don’t have a vaccination scar. Richard E. Rupp, a pediatric doctor at the University of Texas Medical Branch at Galveston, confirms that 1972 marked the end of routine use of the vaccine: “The military and some laboratory workers continued to get that vaccine after that date,” he says. “In other words, most people under the age of 40 shouldn’t have a smallpox vaccine scar.”

My parents — both born in Iran in the 1960s, where smallpox vaccinations would continue to be administered until the disease was eradicated in 1975 — sport their own small, crater-like scars that appear like woven skin on the flesh of their deltoids. “My dad asked the doctor to vaccinate me on the bottom of my foot,” says Keyhaneh, a Persian woman who was born in 1966 and immigrated to the U.S. in 1979. “He didn’t want the scar to be visible.” Of course, none of these wearers of vaccination scars remember much about how they got them. “I was really young,” my dad tells me. “The mark used to be much lower on my arm, but as I’ve gotten older, it’s moved up.”

Vivian Shirvani, an infectious disease specialist in L.A. who has studied medicine in both Iran and the U.S., says that for aesthetic reasons, scarring of any kind, especially for women, was something you wanted to avoid. “It was perceived as damaged goods,” she says. “But the reason it was recommended that a patient receive the vaccine on their arm was because it was the only way to know if someone was immune. The scar meant you were vaccinated — it was easily verifiable on the arm, since you couldn’t ask ladies to take off their pants to see the scar on their butt. But anyone could lift up their sleeve.”

Ironically, Shirvani says that although it was unlikely, the vaccine scar didn’t necessarily indicate that a person was immune. “The vaccine was operator dependent,” she says. “If the person who is doing it doesn’t know how to administer the vaccine, it will leave a lot of scar with no efficacy.”

Also referred to as the “round scar generation,” these pro-vaxxer-or-die folks made it so that future generations — even those who stubbornly renounce the miracles of modern medicine — would no longer have to worry about the possibility of contracting this astonishingly deadly disease. “Almost two centuries after Jenner published his hope that vaccination could annihilate smallpox, on May 8, 1980, the 33rd World Health Assembly officially declared the world free of this disease,” reports the CDC. “Eradication of smallpox is considered the biggest achievement in international public health.”

However it was administered — scraped onto the skin, administered via jet gun or injected using a bifurcated needle — the smallpox vaccine was likely to leave its imprint on the flesh. “The vaccine used to eradicate the disease is a live virus,” says Rupp. “It was scratched into the skin on the shoulder with a funny looking needle, where it would cause a scab. The lesion would heal in two to three weeks and more often than not left a scar.” He adds that the scar isn’t due to the application process, but rather the live vaccines causing an actual infection at the site. “The virus/bacteria grows and damages the skin,” Rupp explains. “Our bodies eliminate the infection, but healing the damage frequently leaves the scar. Some people heal better than others or eliminate the infection faster, so they may not scar. Just like people who fall and scrape the knee, some scar and others don’t.”

Rupp adds that the smallpox vaccine isn’t the only one that leaves its mark. “The other vaccine that causes a scar is the Bacillus Calmette-Guerin vaccine (BCG), used to prevent tuberculosis and meningitis in small children,” says Rupp. “Nowadays it’s only given in countries where TB is common, usually developing countries. The BCG is given shortly after birth and is a live bacteria injected just under the skin. It causes a sore that takes upward of three months to heal.” Generally speaking, the difference between the BCG scar and the smallpox vaccine scar, according to Rupp, is that “smallpox causes an ‘innie’ scar and BCG an ‘outie,’ scar,” he says. Basically, the BCG vaccine scar has a raised center, while the smallpox vaccine scar is depressed, with lines that radiate to the edges.

Interestingly, unlike the smallpox vaccine, the BCG vaccine isn’t considered a particularly good one, at least for grown-ups. “The efficacy of the BCG vaccine in adults is indeed poor, [but] it’s very effective at preventing meningeal TB in children, a very severe form of tuberculosis with a high fatality rate,” says Alice Zwerling, an assistant professor at the School of Epidemiology and Public Health at the University of Ottawa. “Most countries, like Canada, that have discontinued mass vaccination due to decreased TB incidence, still offer BCG vaccine on a case-by-case basis to infants at high risk, or who are traveling to areas with high TB incidence.”

Rupp agrees, adding that the vaccine varies a lot from one country to another, meaning some of the vaccines may be better than others. “There’s a lot of ongoing work to develop a vaccine that works better for all ages,” he says. “Although no one knows for sure, it seems unlikely that a replacement vaccine will cause scars.”

According to Healthline, the most modern iteration of the smallpox vaccine is unlikely to leave a scar, either. In 2003, the smallpox vaccine was administered to 39,213 civilian health-care and public health workers in 55 jurisdictions to prepare the U.S. for a possible terrorist attack using the smallpox virus, per the CDC. “Of the more than 37,500 civilian workers who received the smallpox vaccine in 2003, an estimated 21 post-vaccination scars occurred, according to the journal Clinical Infectious Diseases,” per the same Healthine report. Rupp adds that a live virus vaccine given in the muscle — via the intramuscular route into the deltoid — definitely wouldn’t leave a scar on the skin. “So that could be one way around a scar,” he says. “Another way is to use a dead virus, or some component of the virus and do something to make it more immunogenic. Because it isn’t live, it won’t cause a scar. These things are done with other vaccines.”

As for that potential smallpox terrorist plot, it does continue to pose a threat, according to the CDC. Worse, in the unlikely event that such an attack occurs, Shirvani isn’t convinced that those who wear the vaccination scar would still be immune. “We don’t know if the vaccination is lifelong, because no studies were done after the virus was eradicated to determine its continued efficacy,” she explains. 

Biological Armageddon aside, though, for those who still have their vaccination scar, it remains a stamp, a mark indicative of a time when humankind bested at least one virulent fate. “It shows us we did it once,” says Shirvani. “So if we need to, hopefully, we can do it again.”