Facebook will die out "like the bubonic plague" "Ideas, like diseases, have been shown to spread infectiously between people before eventually dying out, and have been successfully described with epidemiological models," the authors report in a paper entitled "Epidemiological modelling of online social network dynamics." "Ideas are spread through communicative contact between different people who share ideas with each other," they say, adding that users "ultimately lose interest with the idea and no longer manifest the idea, which can be thought of as the gain of 'immunity' to the idea." Facebook is due to update investors on its latest traffic numbers at the end of the month. Its most recent figures, released in October, showed nearly 1.2 billion monthly active users. But the company's chief financial officer David Ebersman admitted on an earnings call with analysts that during the previous three months: "We did see a decrease in daily users, specifically among younger teens." Web experts said that the decline in desktop traffic to Facebook may be partially explained by the fact that many people now only access the network via their mobile phones. According to estimates, 870 million people use Facebook via their smartphones each month, which could explain the drop in Google searches. Users accessing the site no longer do so by typing the name of site into Google. Despite the grim forecast, investors appear to be untroubled. Facebook's share price reached record highs this month, valuing the company founded by Mark Zuckerberg at £85 billion.