Beijing:  China's Health Ministry issued a nationwide alert on Saturday in an effort to control a virus that has caused the deaths of 22 children in one city and shows signs of spreading.

Health bureaus around the country must step up monitoring for hand, foot and mouth disease following a "relatively large" outbreak in the central city of Fuyang, the Health Ministry said in a notice on its website.

The ministry warned that cases were more numerous this year than in recent years and that the peak for transmission would likely come in June and July.

The warning has been prompted by a jump in cases in the Fuyang outbreak of Enterovirus 71, or EV-71, a type of hand, foot and mouth disease.

Up to Thursday night, 3,321 cases of the virus were reported. Besides the 22 deaths, 978 people remain hospitalised, 58 of them in serious or critical condition, the ministry said in a separate statement.

Meanwhile, state-run Xinhua News Agency reported that preliminary tests showed an 18-month-old boy who died on Friday in southeastern Guangdong province was infected with EV-71, and a second suspected death is under investigation.

Cases of hand, foot and mouth outbreaks, but not necessarily EV-71, have been reported in at least two other provinces.

"Health bureaus at all levels must recognise the importance and urgency of preventing the spread of infectious diseases and must put priority on preventing and controlling the spread of infectious diseases," the ministry said in its nationwide order.

Hand, foot and mouth disease are viruses that cause fever, mouth sores and rashes with blisters.

Spread by contact with the mucus discharge or stool of infected people, the viruses mainly strike children 10 years and younger, and in some cases can cause fatal brain swelling.

The outbreak is another concern for the communist government as it gears up to welcome hundreds of thousands of foreigners for this summer's Beijing Olympics and deals with unrest in Tibetan areas of western China.

It is also an uncomfortable reminder of the SARS pneumonia outbreak in 2003, which Beijing tried to cover up but then adopted drastic measures to control.

State media reported earlier this week that the government's response in Fuyang had been slow, allowing rumours to spread about the outbreak.