Spreading of viruses

Question

Dear expert team,
it is the time of colds again and it also got me right. In the waiting room of my general practitioner I observed that nearly all patients coughed in their hands and touched the doorhandle afterwards. Now I ask myself, if it is known, how long the viruses survive on smooth surfaces (doorhandles or banisters)? Do I really take the viruses in my hand when using the doorhandle? I try to stick to "no handshake", would however wish that many more persons would cough in the crook of the arm. Many thanks for you efforts.
Yours sincerely,

Answer

Dear questioner,
many thanks for you interesting and especially also relevant question. In principle, the survival of viruses depend on the type of virus. As a rule, the for you relevant viruses which lead to infections of the upper and lower airways, survive a few hours, however can well still be detected for up to 24 hours. Here also the amount of viruses plays a role. The transmission of all for you relevant viruses is however avoidable efficiently by simple hygienic measures, like regular disinfection of the hands and of course, as you mention right, "no handshake" and coughing in the crook of the arm.
Unfortunately these hygienic measures gained not exeptance well in us as physicians nor in the population. In your situation it is always worth it to disinfect the hands properly, which provides an effective protection. Of course it is like this, that the viruses on your hands do not harm you but they have to come into contact directly with your mouth and nasal mucosa. If you therefore have no contact with your hands to your nose resp. mouth (what I assume), the risk of infection is very small even without an immediate disinfection.
I hope to have helped you further, best regards,
Dr. med. Markus Hofer, Zurich, Switzerland

23.11.2010