Typhoid fever caused the Plague of Athens that devastated the city, according to a study of DNA from burial pits.

Researchers collected DNA from teeth to trace the source of the plague, which shifted the balance of power between Athens and Sparta and led to the decline of Athen's Golden Age.

It's thought that up to a third of Athenians, including their statesman, Pericles, perished in the epidemic.

Historians say the plague began in Ethiopia, passing through Egypt and Libya to Greece in 430-426 BC.

In the fifth century B.C., Greek historian Thucydides described the outbreak after recovering from it himself. Until now, researchers have only had his descriptions to go on for identifying the cause of the outbreak.

Investigators haven't been able to agree on the type of plague, with bubonic plague, smallpox, anthrax and measles all considered possibilities.

Manolis Papagrigorakis of the University of Athens and his colleagues used dental pulp samples from a mass burial pit in the city's Kerameikos cemetery, dated to the time of the outbreak, to retrieve bacterial DNA.

The DNA sequences didn't point to the presence of plague, anthrax, tuberculosis or cowpox.

But the sequences did resemble those from the modern day strain of salmonella that causes typhoid fever, the team reports in the Jan. 18 online version of the International Journal of Infectious Diseases.

"The results of this study clearly implicate typhoid fever as a probable cause of the Plague of Athens," the team wrote.

"We believe this report to be of outstanding importance for many scientific fields, since it sheds light on one of the most debated enigmas in medical history," Papagrigorakis said in a statement.

Typhoid fever is transmitted by contaminated food or water. It is now most common in developing countries.