Alerte à la grippe porcine, premiers cas signalés en Europe[en] 

The WHO's decision came after EU Health Commissioner Androulla Vassiliou had warned against non-essential travel to Mexico and the United States, and Spain had reported the first confirmed case of swine flu. 

Vassiliou said "personally, I would try to avoid non-essential travel to the areas which are reported to be in the centre of the clusters in order to minimise the personal risk and to reduce the potential risk to spread the infection to other people. I would also suggest to travellers to seek immediate medical advice if they have any of the symptoms described'. 

EU foreign ministers held talks on Monday in Luxembourg regarding the outbreak, and EU health ministers are also due to hold an emergency meeting next Thursday (30 April). 

In the meantime, Spain confirmed Europe's first case of swine flu. A young man was kept in isolation after having contracted the illness. The 23-year-old man had recently returned to Spain from Mexico, where the outbreak began. 

According to recent data officially reported by the Spanish regions to the health minister, in Spain, there are 20 patients suspected of having the A/H1N1 virus. All of them, including the patient who tested positive in Almansa, are in stable condition and "responding well to treatment," and none of the cases are serious, Spanish Health Minister Trinidad Jimenez said, stressing that "the situation is under control". 

Other cases of suspected swine flu are under investigation in France, Denmark, Sweden and Switzerland. 

The WHO decided to raise the alert level after experts had held hours of emergency talks on whether to raise the alert level to phase four from phase three in the wake of the outbreak, which has killed up to 149 people in Mexico and spread to the United States, Canada and Europe. 

Phase four relates to the human-to-human spread of a new virus able to cause community-level outbreaks, according to the WHO's revised six-point scale. The level also indicates that there is a significant increased risk of a pandemic, but does not indicate that it is a foregone conclusion. 

European sources say that there are at least three measures which should be taken: boosting prevention measures in airports, running information campaigns directed at European passengers and strengthening cooperation between member states regarding potential transfers of vaccines and medicines to partners in need.