Five people are being examined for suspected swine flu in Switzerland, the Federal Health Office confirmed on Monday.
All five are suffering from flu symptoms and have recently returned from Mexico. They visited their doctors on Saturday after a general appeal by the health authorities for ailing travellers to have check-ups with their doctors.
Switzerland had stockpiled enough doses of the Roche-produced drug Tamiflu, effective in fighting swine flu, to supply a quarter of the population in case of a pandemic, the health office said. GlaxoSmithKline's alternative, Zanamivir, is also available.
A national hotline has been set up to advise people on the potential dangers. Health officials say they are continuing to monitor the situation.
There is currently no vaccine and the test to diagnose the swine flu virus is expected to be available in Switzerland within ten days.
The virus has killed more than 100 people in Mexico, the outbreak's epicentre, and sickened another 1,600. There are confirmed cases in the United States, Canada and Spain. On Monday the European Union health commissioner advised Europeans to avoid nonessential travel to Mexico and the US.
Swine flu is an influenza A virus, carrying the designation H1N1, and is spread by sneezing, coughing or when people pick up the virus from their hands. It is believed to have originated in pigs, but the Mexican government and the World Health Organization have ruled out any risk of infection from eating pork.
swissinfo with agencies