Cranberries are already known to prevent urinary tract infections by reducing the power of certain E. Coli bacteria to stick to the urinary tract walls. This action is sufficiently well documented to support a health claim for the fruit in France.
Now researchers at the Kaohsiung Medical University in Taiwan have round that a compound called proanthocyanidin A-1, isolated from the evergreen shrub Vaccinium vitis-idaea and also known as lingonberry or partridgeberry, significantly suppressed herpes type 2 infection in vitro without any toxic effect.
HSV-2 or herpes simplex infection causes cold sores and genital herpes. Although these common infections can be cured, the current clinical anti-herpes drug acyclovir is encountering acyclovir-resistant strains of herpes viruses.
Chun-Ching Lin and his team said that the cranberry compound did not reduce the infectivity of the virus but did reduce the effects of the infection by preventing viral attachment and penetration, and disturbing the late stage of infection.
"It was concluded that proanthocyanidin A-1 suppressed HSV-2 infection through many modes of action and thus merits further investigation," write the authors in the Journal of the Science of Food and Agriculture (doi: 10.1002/jsfa.1958).
Further studies are required to clarify the mechanism behind the plant's action on herpes and evaluate its effects in humans.
The plant is already used in a treatment for stomach disorders and its flowers are also dried to produce remedies for lung ailments.
Last year researchers reported that an extract from the common herb known as 'self-heal' (prunella vulgaris) may be a powerful new herpes treatment, as it was found to contain a lignin-carbohydrate complex with potent activity against herpes infections in animal studies.