Japanese Apricot (Prunus mume), known as "ume" in Japan, has a long history of use in East Asian traditional medicine. It has been consumed as pickled plums (umeboshi) or as extracts, and is traditionally believed to help prevent or alleviate symptoms of infectious diseases, including influenza. The use is rooted in folk practices, where ume is thought to have properties that "purify the blood," "detoxify," or "strengthen the body’s resistance to illness." Some traditional Japanese and Chinese medical texts mention the use of ume preparations to support general immunity or to manage fevers and colds, which by extension have included influenza-like illnesses.

Scientific research on Japanese Apricot and influenza is limited. A few in vitro and animal studies suggest that certain compounds found in ume, such as triterpenoids and polyphenols, may have antiviral or immunomodulatory effects, but robust clinical evidence in humans is lacking. The traditional use is therefore supported mainly by historical practices and anecdotal evidence, rather than by strong, well-controlled clinical trials. Most modern reviews conclude that while ume has plausible biological activities, its efficacy against influenza in humans remains unproven.