As of 06:00 GMT Friday, the World Health Organization, which on April 29 raised the flu pandemic alert from 4 to 5, said 24 countries had officially reported 2,384 cases of the infection, commonly known as swine flu, with a total of 44 fatalities.
Earlier the United States sent samples of the A/H1N1 swine flu virus to Russia, where scientists will conduct tests and develop a vaccine.
A spokesman for the Epidemiology Central Research Institute said on Thursday that Russian scientists had developed tests to detect the A/H1N1 virus.
Despite the dramatic media reports that accompanied the recent outbreak of swine flu, leading scientists say the virus is a mild strain and only a further mutation would make it a serious threat. Swine flu deaths in Mexico, the worst hit by the virus, are around average for seasonal flu fatalities.