MADRID - The World Health Organization (WHO) is likely to raise its flu alert to the top of its six-point scale and declare a pandemic, its director-general indicated in an interview published yesterday.

WHO chief Margaret Chan also warned against over-confidence following a stabilisation in the number of new cases of the H1N1 strain in Mexico.

"Phase 6 does not mean in any way that we are facing the end of the world. It is important to make this clear because (otherwise) when we announce phase 6 it will cause unnecessary panic," she told Spanish newspaper El Pais.

"Flu viruses are very unpredictable, very deceptive...I'm not predicting the pandemic will blow up, but if I miss it and we don't prepare, I fail. I'd rather over-prepare."

Last week, the United Nations agency raised the alert level twice, from 3 to 5. Before going to phase 6, it would need to see the virus spreading within communities in Europe or Asia.

A declaration of a full pandemic would signal governments to institute pandemic response plans, which may include measures affecting hospitals, schools or public events.

In Singapore, the Home Quarantine Order (HQO) kicked in yesterday, the Ministry of Health (MOH) reported.

Travellers arriving within seven days of leaving Mexico will be quarantined for up to seven days. One foreign resident and two Singaporeans have been issued HQOs.

Meanwhile, of 27 cases investigated here, none have turned out to be H1N1 cases.

MOH reiterated that the public is strongly advised to exercise caution with travel to areas affected by H1N1.

If travel is unavoidable, take precautionary measures like avoiding crowded areas and maintaining high standards of personal hygiene.