From the article:

’There is much scepticism on herbal medicine but what our results illustrate conclusively is that this herb is able to kill the virus and we can actually demonstrate how it kills the virus,’ says Langland. ’It takes this herb out of the realm of folklore, and into the area of true scientific evidence.’

The team made extracts of S. purpurea and found that it was highly effective at inhibiting the replication of the virus in rabbit kidney cells. They then looked at the replication cycle of the virus and found that the herb inhibits mRNA synthesis, halting production of proteins vital for replication. ’Other drugs are being developed against smallpox, but S. purpurea is the only known therapy that will target the virus at this point in the replication cycle,’ says Langland.

’The extract blocks early transcription appearing to have a distinct mechanism of action from that of two other antivirals currently in clinical trials,’ says Mark Buller, a virologist at Saint Louis University, Missouri, US. ’The results are very compelling, and support the need to further evaluate the purified active ingredient in small animal studies.’

’With smallpox, it is obviously impossible to see if this herb is effective in the human body unless a bioterror release of the virus occurs,’ says Langland. ’We are in the process of doing animal studies to confirm our results in at least this type of whole animal system.’