Chinese disease-control experts joined with armed corps Sunday to begin large-scale disinfection of the debris and ruins of quake-hit Yushu County in northwest China's Qinghai Province.

The disinfection aims to prevent water pollution, marmot plagues and outbreaks of respiratory and intestinal diseases in the wake of the disaster, local authorities said.

"The 7.1-magnitude earthquake increased the chance of a pneumonic plague outbreak spread by marmots," said Jie Xuehui, a provincial official overseeing public health.

Organized by the provincial agriculture and animal husbandry departments, six teams will work to prevent animal epidemics and assist with the disinfection work.

The quarantine team consists of 40 staff from provincial animal disease control departments, veterinarian and hygiene-monitoring authorities, and 70 college students from institutions affiliated to the departments.