A highly infectious virus has claimed the lives of 24 children in China, prompting authorities to issue a nationwide health alert in an effort to control the outbreak.

The virus known as enterovirus 71 or EV71 has infected 5,151 children in central Anhui Province, the official Xinhua news agency on Sunday quoted regional health authorities.

The worst hit city of the province is Fuyang, about 750 km south of Beijing, with a total of 362 cases recorded, Xinhua said, adding that 22 children had died.

“That's an extraordinarily high case fatality rate, and that's what caught our attention. Otherwise, it would have passed under the radar,” Peter Cordingley, representative for World Health Organization's regional Western Pacific office, said, as quoted by the Associated Press.

EV71, which causes hand, food and mouth disease, is a childhood illness found worldwide that spreads with saliva, feces, fluid secreted from blisters or mucus from the nose and throat. Symptoms typically include fever, skin rashes and sores inside the mouth and on fingers and toes.

The illness has no specific treatment, but children usually recover quickly without problems. However, there are cases when the illness can result in a more serious form that can lead to paralysis, brain swelling or death.

The outbreak of EV71 comes amid preparations for the Olympic Games, already tarnished by unrest among Tibetans in western China and an international torch relay disrupted by protests. But, WHO China representative Hans Troedsson told a news conference that the outbreak is not “a threat to the Olympics or any upcoming events…This is a disease mainly affecting young children.”

He also added that the illness usually peaks in June or July, which means there could still be an increase in infections as the weather warms up. The disease thrives in hot climates, and Asia has seen increased occurrences in recent years, including in Singapore, Vietnam and Taiwan.

Due to the gravity of the situation in China, the Ministry of Health ordered health authorities across the country to report all cases within 24 hours. Officials would visit nurseries and primary schools to educate staff on hygiene and prevention steps, and Chinese scientists would step up research into the disease.

The ministry also added that special equipment was being installed in children’s wards of Fuyang hospitals to treat patients, while local authorities were strengthening supervision of food safety and water quality in an effort to stop the disease from spreading.

“Local Communist Party and government officials are on high alert. Health authorities are urgently taking measures to prevent the disease and treat seriously ill children,” the health ministry said in a statement.