China's Health Ministry said Thursday the health sector had treated 4,910 people injured in the quake, among which 846 cases were severe as of 5 p.m..

There was no outbreak of epidemic or public health incidents in the quake-hit area, according to the ministry

Yushu, in remote Qinghai Province, was jolted by a 7.1-magnitude earthquake Wednesday, which has left 617 people dead, 9,110 injured and 313 missing.

The ministry instructed quake relief medical teams go all-out in treating severe cases to reduce the death toll, and focus on epidemic prevention, especially to stop an outbreak of plague.

The ministry also stressed safety of food and drinking water, and directed health crews to inform quake victims and rescuers about disease prevention strategies.

The health ministry of People's Liberation Army (PLA) has also dispatched a quake-relief crew staffed by 600 health personnel to the quake zone.

So far, 235 ambulances carrying 1,290 quake-relief medical workers are traveling to the affected area, with more leaving Friday.