During the 16th century, a young woman lived with a face covered with sores that hinted that she likely had tertiary syphilis, a late-stage infection that can often lead to death. Her case of the sexually transmitted infection was so severe that centuries later, her skull remains riddled with bone lesions. Now, researchers have created a facial approximation of the woman as part of a new study (opens in new tab).

While not much is known about the woman's identity, she lived to be between 25 and 30 years old and her body was excavated from a cemetery at the Skriðuklaustur monastery in Iceland about a decade ago. In addition to having syphilis, her skeleton revealed that she had osteoarthritis and dental enamel hypoplasia, a tooth defect caused by malnutrition in childhood, according to an analysis of a 3D model (opens in new tab) of the skull provided by the Northern Heritage Network, an online archive of historical skeletons.

Cícero Moraes (opens in new tab), a Brazilian graphics expert and one of the study's authors, was struck by the lesions marking her skull and realized that he was looking at his next study subject.

"Tertiary syphilis translated into the approximation in a very impactful way," Moraes told Live Science in an email. "It's disquieting to see a face that looks like that, losing part of its structure, and so severe that an injury reaches the bones."

Although the skull's lower jaw was missing, Moraes was able to use the 3D model as a guide, applying virtual skull and tissue markers to help create the curvature of the deceased woman's face. He also examined other skulls of females of European descent who died around the same age as the woman in the database, as well as the contours of a virtual donor, to create the final facial approximation.

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"The cause of death — having only the skull as a reference — is very difficult to stipulate," Moraes said, "but syphilis clearly brought many problems to that individual."

Unlike today, when antibiotics such as penicillin can quickly eliminate the disease, during the 16th century, people of European descent often relied on herbal medicines derived from holywood (Guaiacum sanctum) and skin ointments containing mercury to relieve symptoms. Sweat baths were also popular and were incorrectly thought to help eliminate "the syphilitic poisons," according to a 2021 article in the Journal of Military and Veterans' Health (opens in new tab).

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The final "didactic work" features swirls of lesions stretching across the woman's right cheek and creeping up to an open gash on her forehead. Researchers opted to give the woman blonde hair to make her more lifelike so that the approximation could provide "an example of the development of the disease in an individual [and shows] how syphilis can become something very serious if not properly treated," according to the study.

"It's evident that today, with the medicines we have at our disposal, a situation like the approximation is very unlikely to happen," Moraes said, "but improbable doesn't mean impossible."