Earlier this year, Xiao Bing was infected with Methicillin-resistant Staphylococcus aureus, better known as MSRA, a so-called superbug that renders commonly used antibiotics ineffective.

In May, doctors at the ear, nose and throat department of the First Affiliated Hospital of Fujian Medical University diagnosed the 11-year-old from Fujian province, East China, with acute sinusitis. They prescribed a two-week course of Cephalosporin, a common treatment for the ailment, but Xiao's condition failed to improve and his symptoms, such as a runny nose and cough, remained severe.

At a loss, the physicians took samples of Xiao's nasal discharge, which tested positive for MRSA. In response, they prescribed Vancomycin, a strong antibiotic, and Xiao's symptoms abated after a week on the new medication.

Bao Yong, head of the respiratory disease department at the Third People's Hospital of Chengdu in the capital of Sichuan province, said patients are not usually tested to identify the exact strain of bacteria afflicting them.

That's because cases are usually concentrated among older people, who have poor immunity, are frequently hospitalized and have complicated medication histories, he said.

"Most antibiotic-resistant bacterial infections are detected in hospitals," he said, although he stressed that Xiao was more likely to have contracted the resistant bacteria outside of the hospital.

Microorganisms, including the drug-resistant kinds, exist widely in the environment, mainly in the air and soil, and in the bodies of both animals and humans, which may result in people becoming infected through daily interaction, he said.

Xiao's case demonstrated that "community spreading of resistant germs is increasing", he added.

Bao urged the authorities to strengthen management of antibiotic use in health facilities and to block loopholes in the agricultural sector as quickly as possible.