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Why you should clean your cellphone — frequently

REUTERS/Regis Duvignau
The cellphones in the experiment were most likely to be contaminated with five bacteria commonly found in the environment, including on human skin and in the mouth and nose.

Do you clean your cellphone regularly?

You’ll want to after reading the results of an experiment recently conducted by BuzzFeed health reporter Caroline Kee.

Kee, who admits to having “a weird obsession with germs and diseases,” used special kits to swab 20 phones owned by her BuzzFeed coworkers, and then gave those swabs to microbiologist Susan Whittier at the Columbia University in New York City.

Whittier transferred the swabs to prepared petri dishes, and then waited a few days to allow any microorganisms on the swabs — specifically, bacteria, fungi or molds — time to grow so they could be identified.

Whittier was more than surprised by the results.

“I went into it thinking probably 50 percent of the plates would grow something, so I was really shocked when 100 percent of the phone cultures grew a lot of germs,” Whittier told Kee.

Lots of harmless bacteria

Not all the microorganisms that grew in the petri dishes were pathogens, or ones that cause disease. In fact, the phones were most likely to be contaminated with five bacteria commonly found in the environment, including on human skin and in the mouth and nose. As Kee explains, these bacteria are usually harmless:

  • Staphylococcus epidermidis (not aureus): If you were to just swab your skin directly, this is what you’d find, Whittier says. Staph epidermidis bacteria is totally normal and it would get on the phone from regular daily use, like touching it or talking on it.
  • Micrococcus: This makes up the normal skin flora, especially on the face, Whittier says. Everyone has different skin bacteria, and some people have either more Micrococcus or staph, but it depends on the person. It can get on your phone if you touch your face a lot or talk on it often.
  • Streptococcus viridansStrep viridans lives in the mouth and throat, so it’ll get on your phone from talking or from your fingers after touching your lips, after coughing, etc. It’s usually harmless, but it can also cause infections at very high levels in vulnerable people, and rarely it can pass from the mouth to the genitals to cause [urinary tract infections].
  • Moraxella: This is from sinuses and it’s often found in people with recurrent sinusitis or post-nasal drip. It isn’t as common as strep, and in high levels it can cause inner ear and bloodstream infections in children and immunocompromised people, says Whittier. It’s still a pretty normal thing to find on a phone.
  • BacillusBacillus is a very common bacteria from the environment, so it’s basically a sign that you’ve been outdoors. A lot of Bacillus means the phone is super dirty, but not with anything that will make you sick — just literal dirt. It could get on a phone if it’s been outside or from touching surfaces before you phone.

More worrisome contaminants

Several of the phones, however, contained at least one disease-causing bacterium or fungi, which, as Kee notes, “was a little alarming.”

MRSA. One of these pathogens was methicillin-resistant Staphylococcus aureus (MRSA), a bacterium that has become resistant to many antibiotics, including methicillin (thus its name). MRSA can cause life-threatening bloodstream infections in vulnerable people, particularly those with open wounds or with a suppressed immune system. Although MRSA is primarily a problem in hospitals and nursing homes, it is also transmitted in other settings.

A small proportion of people carry MRSA in their nose or mouth without any problems, and “the potential for a little MRSA on a phone to cause disease in a healthy person is very low,” Whittier told Kee.

Still, “it’s a little worrisome for a phone to test positive for MRSA,” she added, “because it isn’t part of our normal flora.” 

Staph. Also found on the phones was Staphylococcus aureus (staph), which is a common cause of boils and other skin infections. About half of the population carry staph on them — on their skin or in their respiratory tract or nose — without suffering any consequences, but if it gets into an open wound, it can cause serious, life-threatening illnesses, including bloodstream infections, pneumonia and bone or joint infections. 

Staph infections are a particular problem in gyms. “It’s important to wipe down gym equipment with antibacterial wipes before and after you use it and put your phone on a paper towel first to avoid picking up staph and MRSA,” Whittier told Kee.

E. coli.  One of the phones contained Escherichia coli (E. coli), a fecal organism that can cause serious food poisonings and even death.

“E. coli on a phone could be from the person’s stool if they didn’t wash their hands or another person’s stool if the phone went into a public bathroom because fecal matter sprays everywhere when the toilet flushes,” Whittier said.

“This is why you shouldn’t bring your phone to the bathroom or use it while eating,” writes Kee. “Interestingly enough, the guy who had this on his phone actually got sick from a burrito contaminated with E. coli a month ago — so it made sense.” 

Candidas albicans. Two phones also tested positive for Candidad albicans, a common type of yeast that is usually harmless. However, in vulnerable people  — especially infants and those with suppressed immune systems — it can lead to serious illnesses. 

Simple preventive steps

As Kee points out, it’s unclear how these microorganisms got on the phones. Some are probably ones that naturally occur on the bodies of the phones’ owners. But others may have been transmitted to the phone by someone else who used the device or from a contaminated surface that the phone owner touched.

“At the end of the day, nobody needed to be super worried about their results,” says Kee. “But, sure, the people who had pathogens should probably clean their phone at some point and maybe wash their hands more carefully.” 

Taking those simple steps can make a big difference. The owner of the phone that grew the fewest organisms told Kee that she never brings her phone to a bathroom, never uses it while eating or at the gym — and cleans it weekly.

FMI: You can read Kee’s article — complete with colorful photos of the pathogen-laden petri dishes — on BuzzFeed’s website

Comments (1)

  1. Submitted by Jim Million on 06/06/2016 - 12:54 pm.

    Ferry Cross the MRSA

    More good reasons to expedite cell phone implant technology.
    The numerous bacterial locations noted do beg the question, “But where?”

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