Schools in York are on high alert as foreign students prepare to start the new term in the shadow of the Sars disease.

Pupils from Hong Kong who attend The Mount School in York have been told to return ten days early and to undergo a medical examination before term starts.

Meanwhile some students at Queen Ethelburga's College at Ouseburn have not gone home for the spring break to their families in the Far East, where the disease is most prevalent.

A memo to staff and students at the University of York highlights the symptoms of the mystery Sudden Acute Respiratory Syndrome (Sars), which has killed 100 people worldwide.

Education leaders fear the disease could spread among close-knit school and higher education communities.

Scientists are still not sure exactly what causes Sars, which is thought to have infected almost 3,000 people, or how easy it is to spread.

Simon Willis, director of the University of York's International Office, said all staff and students would be issued with a memo to raise awareness of the disease and its symptoms.

He said: "It's obviously something that the university needs to make sure the whole community is aware of, as it is a community of travelling people. It's not just students but academic staff travelling for research and conferences and it's very important that everybody maintains awareness of this issue."

A spokesperson for Queen Ethelburga's College said some children from Sars-hit areas such as Hong Kong and south China had not returned home for the Easter break.

She said: "We are in a position of waiting for the Boarding School Association's decision on what to do, but we don't know when that decision will be made."

Bursar Anne Bolton at The Mount School, Dalton Terrace, said a letter had been sent to all parents to raise awareness of the disease and pupils from Hong Kong had been asked to return early.

Dr Geoffrey Chapman, at Queen Margaret's School, Escrick, said he hoped the school would be able to reopen as normal, although staff were monitoring the situation closely.

Finlay Coupar, director of student affairs at York St John College, said a 100-strong contingent of Chinese students had been offered advice by the college. He said that while the majority of students from the Far East had not returned home for the holiday, college bosses had taken professional advice on the danger of Sars being spread.

David Aked, City of York Council health and safety adviser, said: "We have not been notified of any planned school or educational visits to areas where Sars has been prevalent. However, schools and our other services who plan trips and visits abroad are advised to always contact the Foreign and Commonwealth Office for travel advice if there are any foreseeable problems."

Updated: 10:32 Wednesday, April 09, 2003