It all started a few weeks ago in my communicable diseases module at the London School of Hygiene and Tropical Medicine. During a group brainstorming session we realised how “unclean” keyboards could be. Despite being a public health trainee, I had never thought carefully about how many harmful pathogens could live in a computer keyboard. We always think of how important it is to wash our hands before eating or after sneezing into them; however, when it comes to hand hygiene before or after using a multi-user computer, most of us really don’t care that much.

After doing some research into keyboards’ role in the development of infections, I soon realised that washing hands should be at the top of the list when using a public computer. Staphyloccocus aureus, Enterobacteriaceae such as Escherichia coli or Enterococcus faecalis, and antibiotic resistant Staphylococci (eg. MRSA) are just a sample of what you can find in a keyboard swab culture. Noroviruses, respiratory viruses (such as influenza), yeasts, and moulds can also be found.

“There are pathogens on my keyboard, so what?” you may ask yourself. Viruses and bacteria are ubiquitous and you can find them everywhere. That’s correct. But the truth is that in places, like the UK, where many workers eat lunch at their desk (estimates mention 60%), having all these pathogens on your keyboard can be a problem. First of all, crumbs attract rodents that search for food. Would you feel comfortable knowing that there was a rodents’ night party on your keyboard due to your leftovers? Secondly, a dirty desk can have 400 times more germs than a toilet seat. This can lead to illnesses such as flu or gastroenteritis.

International research shows that respiratory illnesses alone can cause work absence with an annual cost of $137 per worker. Of course, bias may arise when trying to establish causality between keyboard use and these illnesses. However, other pathologies, such as acute gastroenteritis caused by noroviruses (a very infectious virus that is one of the main causes of gastroenteritis in the UK), are easier to track. Outbreaks have been reported internationally: in a school in the USA, 27 students and two staff members were infected by this pathogen. Any of these conditions can lead to work or school absenteeism with consequent loss of productivity and medical costs.

Moreover, due to the increasing prevalence of MRSA asymptomatic carriers in the community, there are concerns about the role of public computers (in a non hospital setting) as reservoirs for these pathogens. This may lead to potential genes transference between bacteria, therefore leading to antibiotics resistance.

All in all, the facts are: keyboard origin infections can be prevented through basic public health measures such as hand washing (with warm water and soap) before and after computer use—especially in multi-user keyboards—as well as through regular computer and work area cleaning with disinfectant wipes. These are simple, fast, and painless measures that can save us all time and money, as well as prevent work or school absenteeism.

More research needs to be done. In the meantime I have chosen to stay on the safe side, wash my hands, and wipe my keyboard regularly. What about you?

Liliana Gomes is a public health trainee currently doing a masters in public health at the London School of Hygiene and Tropical Medicine.

Acknowledgements: I thank my colleagues at the London School of Hygiene and Tropical Medicine, who contributed to this blog by providing some of the literature references, as well as the title of our group work.

Competing interests: “I, Liliana Gomes, declare that I have read and understood the BMJ Group policy on declaration of interests and I have no relevant interests to declare.”