Various bacteria colonies found in the samples. (Photo/www.wccdaily.com.cn)

Ms. Hou, a resident of Xiamen city in east China's Fujian province, noticed red sores festering in her mouth one day after she unwrapped an express parcel with her teeth. Doctors diagnosed it as an allergic reaction, most likely caused by bacteria on the package. Due to instances like this one, some people now believe that there is more bacteria on packages even than on toilet lids and garbage cans.

In order to analyze the bacteria on items in our daily life, reporters from Western China Metropolis Daily connected with two experimental institutions and undertook bacteria testing of express parcels, mobile phones, ATM buttons, elevator buttons and more.

The Chengdu Experimental Center of Medical Research looked at previous data and made a comparison. According to the reports, elevator buttons, ATM buttons and mobile phones had respective bacterial colonies of 2.42, 10.35 and 4.97 per square centimeter.

"In the experiment, we found that the bacteria population on ATM buttons is rather high, and the bacteria colonies on mobile phones are almost ten times that of courier packages. But the superficial areas of express parcels are usually large, so the bacteria population is still not small," said one worker in the research center.

"The more commonly used the items are, the more bacteria they have on their surface, assuming they haven't undergone disinfection. Do not use your mouth to unwrap express parcels. People should wash hands after unpacking parcels and use sterilizing wet tissues to do periodic cleaning of common items," said Peng Shiguo, deputy director of the Fourth People's Hospital of Sichuan Province.