Scientists have long debated what cause the Plague of Athens
The Athenian empire was brought to its knees by typhoid fever, a Greek team of archaeologists has suggested.
A University of Athens team analysed DNA from dental pulp found in a burial pit dating back to 430 BC and linked it to the organism that causes typhoid.
Scientists have long debated the cause of the plague that ended Athenian dominance of the classical world.
The study in the International Journal of Infectious Diseases says a number of diseases were suspected as the cause.
These included bubonic plague, smallpox, anthrax and measles as suspected causes of the epidemic which spread across northern Africa to Egypt, Libya and Greece.
Between 430 and 426 BC the plague killed almost a third of the Athenian population and its armed forces, along with the city's leader and mastermind of Athenian glory, Pericles.
The research team investigated DNA material in three randomly selected intact teeth found in the ancient cemetery of Kerameikos which dates back to the outbreak of the disease.
All teeth were washed and the dental pulp removed was subjected to a series of DNA tests.
The results were compared with the DNA profiles of a seven disease-causing viruses and bacteria.
An ancient strain of the organism causing typhoid fever was found to be present in the dental pulp of all three dental samples.
The team said in their research: "For an infectious disease to be considered as a likely cause of the Plague of Athens, it must, above all have existed at that time.
"Infectious diarrhoeas and dysentery as described by the ancients, imply that typhoid fever was an endemic problem in the ancient world."
The team added that it was the first time microbiological evidence associated with the plague had been analysed.
Previously assumptions about the cause had been based on the narrations of a the 5th Century Greek historian Thucydides.
Earlier research rejected the idea that typhoid caused the plague because of the symptoms described by Thucydides did not fit with the modern day typhoid.
But the researchers said inconsistencies maybe explained by the possible evolution of typhoid fever over time.
Lead author Dr Manolis Papagrigorakis said: "Studying historical aspects of infectious diseases can be a powerful tool for several disciplines to learn from."
Dr Daniel Antoine, lecturer in bioarchaeology and dental anthropology at University College London's Institute of Archaeology, described the work on DNA as solid and said the results were very interesting.
However, he added: "It would be nice to have another lab repeat this work on a larger sample from a Greek site of the same period, before typhoid fever is attributed as the sole 'cause' of the plague, and thus eliminate the possibility of an isolated outbreak of typhoid fever."