Nicaragua's Health Ministry said on Sunday it had ruled out the 15 possible cases of A/H1N1 flu, which included travelers from Mexico.

The Ministry is following up on 211 people who have symptoms consistent with the flu, 40 of whom are under constant observation.

While most are from Mexico, where the outbreak began and 19 people are confirmed dead with the virus, some are also from Costa Rica, which has also reported cases, and from nations in a similar position, Health Minister Guillermo Gonzalez said.

He also said that the World Health Organization has pledged 50,000 flu treatments for the nation, after Nicaragua declared a health emergency on Wednesday.

Anti-flu measures including door-to-door leaflet distribution by the pro-government Citizens Power Councils, the setting up of Health Ministry advice booths in every neighborhood in Managua, so that the population can swiftly receive help and advice if they suffer symptoms of the disease such as high fever, breathing difficulties, muscular pain and headache.

The Ministry's leaflets advise people to wash their hands regularly and avoid kissing and handshakes. Gonzalez also said that eating cooked pork or its products would not spread this disease.