A teacher has become the first New Yorker to die from swine flu since the city recorded its first outbreak of the virus three weeks ago, and hundreds of students and others associated with a Catholic high school in Queens fell ill following the return of several of their number from a holiday in Mexico.

Mitchell Wiener, 55, an assistant principal, died yesterday in hospital, where he had been on a ventilator, said Andrew Rubin, a spokesman at Flushing hospital medical centre in New York.

Wiener's death, though not the first related to swine flu in the US, came on a weekend when it was announced that five more New York city schools were closing, raising the total to 11.

Health officials say four public schools, three of them in the same building, and one Catholic school in the borough of Queens will close today for up to five school days. Eachhad students with flu-like illnesses last week.

Six other schools were closed over the last few days after hundreds of students became ill with suspected flu symptoms.

Meanwhile, the World Health Organisation is looking very closely at the spread of swine flu in Spain, Britain and Japan, a WHO official said yesterday. Japan reported more than 70 fresh cases in one day, mostly among teenagers.

The epidemicwill dominate the WHO's annual meeting opening today in Geneva for five days, bringing together health officials from 193 member states.

The director general, Margaret Chan, will reveal recommendations for production of a vaccine at the meeting. Pharmaceutical firms are ready to begin production, but many decisions have to be made first – such as how much vaccine to make, how it should be distributed, and who should get it.