A sip of unpasteurized sheep or goat's milk may have spelled doom for a medieval Italian man.
A new genetic analysis of bony nodules found in a 700-year-old skeleton from Italy reveal that the man had brucellosis, a bacterial infection caught from livestock, when he died. It's not clear if the disease killed the man, but he likely would have suffered from symptoms such as chronic fatigue and recurring fevers, according to the researchers who analyzed the bones.
This medieval Italian man joins many other long-dead people in getting a postmortem diagnosis of brucellosis. Signs of the disease have been found in skeletons from the Bronze Age and earlier. In fact, the disease predates modern humans: In 2009, researchers reported possible signs of brucellosis in a specimen of the human ancestor Australopithecus africanus, who lived more than 2 million years ago. (10 Deadly Diseases That Hopped Across Species)
The brucellosis-infected Italian came from Sardinia. He was buried in a medieval village called Geridu, which was abandoned sometime in the late 1300s, and was probably between 50 and 60 years old when he died.
Archaeologists found 32 bony nodules scattered in the man's pelvic region, the largest about 0.9 inches (2.2 centimeters) in diameter. Such nodules are often a sign of tuberculosis, a lung infection caused by the bacterium Mycobacterium tuberculosis. Tuberculosis is the most common culprit in cases of calcified nodules, study leader Mark Pallen, a microbial genomist at Warwick Medical School in England, said in a statement.
Pallen and his colleagues sampled one of the nodules and subjected it to a process called "shotgun metagenomics." Instead of searching for a particular DNA signature, shotgun metagenomics takes the approach of simply sampling all the DNA present, just to see what turns up.
To the researchers' surprise, the man did not have tuberculosis. Instead, the bony nodule held the DNA signature of the bacterium Brucella melitensis, the microbe that causes brucellosis.