Singapore  - Child-care centres and kindergartens in Singapore are stepping up cleaning of classrooms as the number of children coming down with hand, foot and mouth disease nears the official "epidemic level," a newspaper reported Thursday.

Last week, 653 people were affected by the disease, 12 short of the Health Ministry's official epidemic level, the Straits Times said.

The number of cases was expected to rise from April to May, one of two traditional peak infection times for the disease with the other being August and October.

There were 4,926 hand, foot and mouth disease cases in the first 13 weeks of this year, compared with 4,423 for the same period last year when a 3-year-old boy died from an inflammation of the brain lining caused by the disease.

Seven Singapore children died from it during an outbreak from 2000 to 2001. Hand, foot and mouth disease usually hits children under 10.

The symptoms are usually mild and include ulcers and blisters in the mouth, rashes on the hands and feet, and fever.

The illness usually passes within a week without treatment, but a small minority of cases become life-threatening, mainly because of neurological complications - such as encephalitis, meningitis and paralysis - as well as lung haemorrhages.

The virus is highly infectious and transmitted through saliva, blister fluid and faeces. There is no vaccine.

For now, no child-care centres have been ordered to close because the cases have been spread out rather than clustered in any particular area. Authorities have closed them in the past several years during the worst outbreaks. (dpa)