When you combine a cellphone's proximity to your ears, nose and mouth with its bacteria-loving warmth, the result can be harmful to your health, The Wall Street Journal reported. This hazard, said Dr. Jeffrey Cain, the president of the American Academy of Family Physicians and chief of family medicine at Children's Hospital Colorado, often goes unnoticed. "Some things we think are personal are actually more public than we imagine." Bacteria from a phone can cause flu, pinkeye or diarrhea, said Cain.

Even though computers, keys, pens and landline phones can harbor germs, many people's cellphones have become extra appendages—never far from the pillow, health club treadmill or restaurant table.

"We're feeding the little creatures," said Dr. Michael Schmidt, a professor and vice chairman of microbiology and immunology at the Medical University of South Carolina. "We've all seen that greasy smear [on the touch screen]. Where there is grease, there are bugs."

A lab tested eight randomly selected phones from a Chicago office for this article. The phones showed no signs of E. coli or staphylococci bacteria. But all phones showed abnormally high numbers of coliforms, a bacteria indicating fecal contamination. Of the eight phones tested by HML Labs of Muncie, Ind., there were between about 2,700 and 4,200 units of coliform bacteria. In drinking water, the limit is less than 1 unit per 100 ml of water.

"The results are pretty bad," said Dr. Donald Hendrickson, president of HML Labs and professor emeritus of medical microbiology at Ball State University. He said the results suggest a lack of hand-washing and proper hygiene.

HML then tested four different cleaning methods, including water, alcohol, Windex Original glass cleaner and Nice 'N Clean electronic cleaning wipes. Alcohol performed best, cleaning nearly 100 percent of the bacteria. Plain water proved to be the least effective method of the four.

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