WHO confirms flu spreads to Cuba, Finland, Thailand

* H1N1 strain infects 5,728 people in 33 countries

* WHO confirms flu strain reaches Cuba, Finland, Thailand

* More cases in Spain, Britain, Panama, Guatemala, Colombia

GENEVA (Reuters) - H1N1 flu has now reached Cuba, Finland, and Thailand, with nearly 6,000 people infected in 33 countries, the World Health Organization said Wednesday.

In its latest tally, which lags national reports but is considered more reliable, the WHO said the number of infections has also risen in several countries including Spain, Britain, Panama, Guatemala, and Colombia.

The recently discovered virus has killed at least 56 people in Mexico, three people in the United States, and one each in Canada and Costa Rica.

WHO Director-General Margaret Chan has raised the flu alert level to 5 out of 6 as a result of its spread beyond the disease epicenter Mexico, signaling that a pandemic is imminent.

She is looking for evidence the hybrid strain is spreading in sustained way in communities outside of the Americas before raising that alert to 6 and declaring a pandemic is under way.

According to the latest WHO count, Spain has 98 confirmed cases and Britain has 68.

While most of those infections have been deemed "imported" cases as a result of people traveling to Mexico, or being in close contact with those who had, WHO experts are watching both countries closely for signs the virus has taken hold in Europe.

North America continues to have the largest number of confirmed H1N1 infections worldwide.

Mexico has 2,059 cases confirmed in WHO labs, the United States has 3,009, Canada has 358, and Costa Rica has eight.

Other countries have the following number of WHO-confirmed flu cases without deaths: Argentina (1), Australia (1), Austria (1), Brazil (8), Britain (68), China (3, comprising 1 in Hong and 2 in mainland China), Colombia (6), Cuba (1), Denmark (1), El Salvador (4), Finland (2), France (13), Germany (12), Guatemala (3), Ireland (1), Israel (7), Italy (9), Japan (4), Netherlands (3), New Zealand (7), Norway (2), Panama (29), Poland (1), Portugal (1), South Korea (3), Spain (98), Sweden (2), Switzerland (1) and Thailand (2).

(For a WHO map of the flu spread worldwide see: www.who.int/csr/don/h1n1_20090513_0600.jpg)

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