Since the latest variant of hand, foot and mouth disease appeared in mid-September it has been identified as the cause of the deaths of four children in Singapore and a three-year-old boy in Johore, the Malaysian state next to to the island republic. More than 1000 children have been treated for symptoms associated with it, with 30 patients being admitted to hospital.

There is no known cure or vaccine for the disease, which mainly affects children under five. It can be caused by about 70 different viruses, including the coxsackie A, which struck in peninsular Malaysia and the Malaysian state of Sarawak on Borneo in 1997, killing 34 children.

The deadliest virus is enterovirus 71 (EV71), which can trigger complications affecting the brain and spinal cord. EV71 is believed to have been responsible for more than 70 deaths in an outbreak in Taiwan in 1998.

Singapore's Health Minister, Lim Hng Kiang, said the Singapore virus had yet to be identified.

Singapore, which has a reputation as the cleanest city in Asia, began preparing for an outbreak of hand, foot and mouth disease after the Taiwan incident, setting up a taskforce of representatives from several ministries, including health, community development and education, and the leading hospitals.

Singapore nurseries and kindergartens may reopen next week as fears of the epidemic, suspected in the deaths of four children, subside, officials said yesterday.

A taskforce member said the disease was "always around".

One of the taskforce's first measures last month was the closure of nursery schools, child-care centres and play areas.

Because it is common for both husbands and wives to work in Singapore, they are forced to put their children in the centres. The situation has provoked many complaints. "A child's life is much more important than our convenience," President S. R. Nathan said.

But the Government appealed to employers to help affected parents by granting them leave or allowing flexibility in their working hours.

Last week, Thailand started screening children arriving from Singapore, examining each young passenger for signs of high fever, rashes on hands or feet, or mouth ulcers, which are symptoms of the virus.

The father of the Johore victim said neither he nor his wife had taken their son to Singapore for several months. But Johore is a major shopping centre for Singaporeans, so it seems likely the disease spread from the neighbouring nation.