A norovirus outbreak hit a kindergarten in Zigong, Southwest China's Sichuan Province reported on Wednesday, infecting more than 50 children and adding to a series of norovirus outbreaks around China in recent months. Photo: CFP

A norovirus outbreak hit a kindergarten in Zigong, Southwest China's Sichuan Province reported on Wednesday, infecting more than 50 children and adding to a series of norovirus outbreaks around China in recent months. 

The Yantan district's health department received reports of kindergarten children vomiting, and confirmed the outbreak as noravirus on Thursday. 

"After epidemiological investigations and nucleic acid tests, the Center for Disease Control (CDC) confirmed that the vomiting was caused by a norovirus infection," the health department said in an announcement. "All the children are in stable condition and are receivingtreatment at a hospital with mild symptoms."

The earliest vomiting case was reported on Wednesday morning, followed by another student in the afternoon. After school, parents continued to report vomiting and diarrhea cases to the kindergarten teachers.

On Thursday morning, most of the infected children were sent to hospital for infusion treatment. Staff at the district's CDC were sampling children and asking about the course of the disease, The Paper reported. 

Follow-up treatment and cause-tracing will be released after medical investigation, the Zigong CDC told the Global Times on Thursday.

As the No. 1 cause of acute viral gastroenteritis, the norovirus infects 685 million people worldwide annually, and has increasingly emerged as a public health issue in China. 

On November 13, a middle school in East China's Fujian Province was hit by a norovirus outbreak, leading to the school's suspension, with more than 30 students infected. On October 29, a number of kindergarten children in Northeast China's Liaoning Province were infected, which led to a temporary shutdown of the kindergarten. Earlier that month, a similar outbreak occurred at a university in North China's Shanxi Province, overwhelming the university's health services. 

There are no norovirus vaccines in the market. In February 2019, Chinese authorities approved a clinical trial for the world's first tetravalent vaccine against the virus. The vaccine, after four years of development, can theoretically prevent 80 to 90 percent of norovirus infections, the Xinhua News Agency reported.

Global Times