Comment on: “High level bacterial contamination of secondary school students’ mobile phones”

Dear Editor,

The recent publication on “Bacterial contamination of mobile phones” (Germs 2017;7:73-7) is very interesting.¹ Kõljalg et al. concluded that “our study showed high level contamination of secondary school students’ mobile phones with potentially pathogenic bacteria to be common, and we hypothesize that this may play a role in the spread of infectious agents in the community.”¹ We would like to point out the fact that bacterial contamination of mobile phones can be expected since the phone is frequently touched by unclean hand and comes into contact with saliva during its use. However, whether the contamination can be the source of disease transmission is a matter that warrants further discussion. Indeed, if one has no open wounds, the direct bacterial invasion from touching the mobile phone is unlikely. The problem might be expected in some uncommon cases such as contamination in the immunocompromised patient ward or the operation room in the hospital.^2,3 Also, nobody should swallow or put the phone into the mouth to allow potential pathogens to directly enter the gastrointestinal tract. The possible concern might be related to the spread of respiratory pathogens such as Mycobacterium tuberculosis, and this is an area where further studies are warranted.