Scientists have found that mobile phones play host to potentially life-threatening bacteria, including E.coli and MRSA.
Their tests found that 92 percent of handsets were contaminated with bugs and some harbour 1,000 types of microbe, the Daily Mail reported.
Although most of the bacteria were harmless, one in six phones had E.coli, which has been linked with dozens of cases of food poisoning and one death in Europe this summer.
E. coli is highly contagious, surviving on hands and surfaces for hours especially in warm temperatures and is easily transferred by touch to door handles, food and mobile phones, where it can be picked up by others.
It originates in faeces and the researchers said it emphasises the need to wash your hands with soap, especially after going to the toilet.
For the study, experts from the London School of Hygiene and Tropical Medicine took samples from the mobiles and hands of 390 people in 12 cities.
A quarter of phones surveyed contained the Staphylococcus aureus bacteria - found naturally in the nose, mouth and skin - which can mutate into the hospital superbug MRSA, emphasising the need for patients and visitors to wash their hands in hospitals.
"This study provides more evidence that some people still don't wash their hands properly, especially after going to the toilet," said Dr Val Curtis of the London School.
The results were released to promote Global Handwashing Day