Health authorities have confirmed the 20th case of the A/H1N1 flu virus in Switzerland.

The latest case, a 39-year-old man from canton Vaud who recently returned from New York, has been placed in quarantine along with members of his family. Another 28 suspected cases of the virus, known as swine flu, are being examined.

Canton Vaud has the highest number of confirmed cases across the country. One cantonal resident contracted the illness in Switzerland.

The authorities said almost all confirmed cases were people who had travelled from a zone with an increased risk of infection, and appealed for anyone suffering from flu symptoms within seven days of travelling to call their doctor. The virus does not currently pose an elevated risk for the general population.

The World Health Organization (WHO) reported on Monday there were 25,288 cases and 139 deaths in 173 countries.

It is on the verge of declaring the first flu pandemic in more than 40 years, but first wants to ensure countries are well prepared to prevent a panic.

Keiji Fukuda, acting WHO assistant director-general, voiced concern at the sustained spread of the new A/H1N1 strain, including more than 1,000 cases in Australia.

swissinfo.ch with agencies

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