Tanacetum vulgare, a flowering herb known as tansy, has been used for centuries in Britain and Spain as an alternative medicine and folk remedy. Now, scientists are saying that it may have applications in the field of sexually transmitted disease (STD).

The antiviral properties of the herb may make it an effective treatment for oral and genital herpes, according to a study published in the journal Phytotherapy Research.

An international team of scientists came to this conclusion after breaking down the plant’s extracts an analyzing each separated compound for its ability to fight viral infections.

Two in particular, 3,5-dicaffeoylquinic acid and axillarin, showed the most promise as effective antiviral agents.

The study focused on tansy’s roots and aerial stalks, which have already seen centuries of use as part of natural insect repellents and insecticides.

Its authors concluded that tansy may one day play in integral role in all-natural therapies for herpes lesions.

In the U.S., genital herpes is relatively widespread. An estimated one in every six Americans between the ages of 14 and 49 has the disease, according to the Centers for Disease Control and Prevention.