London: Smartphone users, beware! Your phone may be teeming with bacteria, including Staph aureus which is a common cause of skin infections, respiratory disease and food poisoning, scientists say.
Long after we have swiped and tapped our smartphones, sent or received personal texts, our devices retain a biological history of our actions, researchers said.
Students at the University of Surrey imprinted their mobile phones onto bacteriological growth Petri dishes to see what they might carry.
After three days they studied the bacteria that had grown in the dishes.
"Most of the bacteria were harmless, but it just shows the invisible life that can lurk on your phones everyday," researchers said.
However, some disease carrying bacteria such as Staphylococcus aureus were also occasionally found.
"Bacteria can utilise many different things as vectors in order to promote their transmission. Insects, water, food, coughs and sneezes, sexual contact, and rain are just a few examples. The mobile phone appears to be no exception this rule," they said.
"The ecological niche on the body for Staphylococcus aureus is the nostrils, so a furtive pick of the nose, and quick text after, and you end up with this pathogen on your smartphone," said Dr Simon Park, Senior Lecturer in Molecular Biology, who started running the project in 2013 as part of a course called Practical and Biomedical Bacteriology.
In one instance, researchers observed a smartphone-shaped colony of Bacillus mycoides.
"This pattern of growth is unique to this bacterium and because soil is its natural habitat, we know that this phone or its user had recently been in contact with soil. Each phone tells a story," Park said.
"From these results, it seems that the mobile phone doesn't just remember telephone numbers, but also harbours a history of our personal and physical contacts such as other people, soil and other matter," Park said.