Apple's popular gadgets including the iPhone and iPad could prove a health risk according to an Australian expert in infectious diseases.

Professor Peter Collignon told The Sydney Morning Herald, his research had found a higher risk of transmitting pathogens from glass surfaces such as iPhones and iPads to human skin.

"You wouldn't have hundreds of people using the same glass or cup, but theoretically if hundreds of people share the same keyboard or touch pad, then effectively that's what you're doing," said the director of infectious diseases and microbiology at the Australian National University.

"The germs we transmit via our hands can frequently have germs that can cause anything from the flu to multi-drug resistant diseases."

A previous investigation by the New York Daily News found that of four iPads tested in two Apple stores, two contained harmful pathogens, including Staphylococcus aureus and Corynebacterium minutissimum.

Dr. Philip Tierno, director of Clinical Microbiology and Immunology at New York University Langone Medical Center, told the newspaper iPads handled by a multitude of strangers were bacteria breeding grounds.

"I'm surprised you found so little. Two things increase the risk. The amount of time one spends on the apparatus, and the number of people who touch it."

An Apple spokeswoman Amy Bessette responded at the time saying: "We clean our products and our stores regularly throughout the day. And we are committed to creating a healthy environment for our customers."

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