Brucellosis can be transmitted from livestock to humans in several ways. One possibility is that the man caught the disease from direct contact with animals — perhaps while slaughtering a sheep or delivering a newborn lamb. Or he could have gotten the disease from drinking unpasteurized milk or eating unpasteurized cheese. The Brucella strain that infected the man was a close relative of modern Italian strains, the researchers found, and sheep and goat herding have long histories in the region.
Brucellosis is also called Mediterranean fever. It still affects more than 500,000 people around the world yearly, though livestock vaccination and dairy pasteurization have hampered its spread.
Today, antibiotics are used to treat people with brucellosis, and no more than 2 percent of infected people die from the disease, according to the Centers for Disease Control and Prevention. In its chronic, untreated form, the disease causes muscle and joint pain, fatigue and depression. The deadliest symptom of the disease is endocarditis, the swelling of the lining of the heart.
The method of diagnosing the medieval man's brucellosis could be used to uncover other ancient diseases, the researchers said. By not honing in on specific DNA signatures, researchers can cast a wider net, they wrote in their report of the case published today (July 15) in the journal mBio.
The team is now using the technique to test an array of samples, from ancient Hungarian and Egyptian mummies to the lung tissue of an early medieval French king, the researchers said in a statement.
"We're cranking through all of these samples, and we're hopeful that we're going to find new things," Pallen said.
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