While Asia considers ways to tackle bird flu, one Japanese company claims that some birds’ nests themselves might provide protection against flu and other viruses.

Functional food makers Combi Corp say their researchers found that swift nests – made entirely from the bird’s saliva and used to make birds’ nest soup – contain high levels of a sticky acid that the body uses to neutralise viruses such as influenza.

The nests, composed of a white gelatinous substance secreted by the salivary glands of the grey rumped swiftlet, will be used to make health foods says the company, though prices may be prohibitive.

Fetching US$30-40 each, one nest can make two batches of soup.