The World Health Organization, which has been stressing the safety and importance of H1N1 shots, on Monday had its own staff vaccinated against the pandemic virus.

Employees wanting the swine flu jabs were taken from the WHO's Geneva headquarters to a Swiss army barracks as part of Switzerland's national vaccination plan against swine flu, WHO spokeswoman Kristen Kelleher told Reuters.

About 1,000 staff members will have, or have had, access to the pandemic vaccine today, she said. Those working in field response teams outside Geneva were vaccinated last week.

WHO Director-General Margaret Chan was out of the country on Monday and her agency could not immediately say whether she had been vaccinated against the virus that she declared a global pandemic in June.

The WHO has repeatedly said the vaccines are safe and should be given first to medical workers and those at highest risk of severe infection -- especially children and pregnant women.

Infection with the highly contagious virus, which causes mild symptoms in most patients but deadly pneumonia in others, gives a person natural immunity.

But doctors are not testing every flu patient to identify whether they have seasonal or pandemic flu, fuelling large appetite for a protective jab against the flu strain that health experts fear could mutate into a more dangerous form.

According to the WHO's latest estimate, the H1N1 flu strain that has circulated worldwide since its discovery in Mexico and the United States in March has killed more than 7,800 people.

Leading H1N1 vaccine makers include Sanofi-Aventis, CSL, Novartis, the AstraZeneca unit MedImmune and GlaxoSmithKline.