Rumors of Facebook’s death have been greatly exaggerated as reports predict a decline in users on the site, but that just means the social network needs to work hard to keep its popularity. Princeton University Ph.D. candidates Joshua Spechler and John Cannarella published research comparing the growth of an online trend to the spread of a disease, which then fades as people become immune to the infection.

Barely a week goes by without Facebook facing one crisis or another, according to the media — usually relating to the fact that US teenagers are using other services more regularly. Most recently, boffins at Princeton used data to suggest 80 percent of users will leave Facebook by 2017. Facebook then humorously debunked that by using the same methodology to ‘prove’ Princeton’s enrolment would halve by 2018, and that the world’s air supply will disappear by 2060. Jokes aside, it is true that Facebook does face concerns. Snapchat is estimated to have 50 million registered users – with some suggesting usage of the ephemeral chat app has tripled among teens over the past year.