When it comes to ordering at a McDonald's, using a traditional counter over a touchscreen kiosk may be better for your health.
A study by U.K. newspaper Metro found gut and fecal bacteria on touchscreens in all of the chain's restaurants it surveyed. It took samples from the screens in eight branches and found that they contained coliform bacteria, a group of microorganisms found in people's intestines as well as in soil and on plants.
Senior lecturer in microbiology at London Metropolitan University Dr Paul Matewele told the newspaper: "We were all surprised how much gut and fecal bacteria there was on the touchscreen machines. These cause the kind of infections that people pick up in hospitals."
Metro's research with the university took swabs from six London McDonald's outlets and two in Birmingham. Listeria, a bacteria that can cause listeriosis and is a concern especially for those over 65 and pregnant women, was found on screens in two branches.
A McDonald's spokesperson said in an emailed statement: "Our self-order screens are cleaned frequently throughout the day with a sanitizer solution. All of our restaurants also provide facilities for customers to wash their hands before eating."
McDonald's introduced touchscreens in the U.K. after trialing them in 2015, and they are also used in markets including Canada and Australia. In June, Chief Executive Steve Easterbrook said that when people use the self-service kiosks they tend to spend more. "What we're finding is when people dwell more, they select more," Easterbrook told CNBC's "Squawk on the Street". "There's a little bit of an average check boost."
It has been quickly introducing touchscreens in its U.S. outlets, bringing them to 1,000 stores every quarter for the next eight to nine quarters, a process that started in June.
Touchscreens may not be the worst offender when it comes to harboring bacteria. An August survey that polled 1,000 people in the U.K. found that more than a third had never cleaned their smartphone and claimed they had more bacteria on them than a toilet seat. Aside from hand-washing to prevent germs transferring, people can buy antibacterial products designed for use on electronic devices.
- CNBC's Sarah Whitten contributed to this report
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