A team of researchers in a recent study found that the entire Roman Empire, which has been known for its advanced sanitation, was infested with parasites. The team found that the empire was infested with higher number of human parasites.

The study's author Piers Mitchell, a lecturer of biological anthropology at the University of Cambridge in the United Kingdom, said, “I was very surprised to find that compared with the Bronze Age and Iron Age, there was no drop in the kind of parasites that are spread by poor sanitation during the Roman period”.

Mitchell told Live Science that despite having extraordinary baths and toilets people in Roman times had bad health due to infestation by parasites.

Romans introduced sanitation technology about 2,000 years ago, which included public bathrooms with multi-seat latrines, heated public baths, sewage systems and drinking water piped from aqueducts, Mitchell said.

Researchers during their study scrutinized through previous research on the empire's intestinal parasites including years in latrine soil, coprolites (fossilized excrement) and burial dirt that contains decomposed human remains.

They found that ectoparasites were more common in the Roman Empire at places where people took bath.

The most widely spread intestinal parasites in the Roman Empire were whipworm (Trichuris trichiura) and roundworm (Ascaris lumbricoides) which are transmitted by the contamination of food with feces, said Mitchell.

He said that the parasites might have spread due to the use of unwashed hands to prepare food or by the use of human feces as crop fertilizer. Another parasite that was found widespread was Entamoeba histolytica, a protozoan that causes dysentery, with bloody diarrhea, abdominal pain and fevers.

The study also found fish tapeworm eggs surprisingly widespread in the Roman empire, in contrast to the evidence from the Bronze and Iron Age.