Swine flu has infected more than 52,000 people in 100 countries and territories and killed 231 people since late March, the World Health Organisation (WHO) reported today, a sharp rise in the toll.
There have been an extra 7,873 cases and 51 more deaths since the last toll released by the UN health agency on Friday.
The United States led a group of countries that have seen dramatic increases in cases of the A (H1N1) virus.
There were an extra 3,594 cases to a total of 21,449, 87 deaths, in the United States, 1,190 more cases in Chile (4,315), where there have been four deaths and 805 extra cases in Canada, with 5,710 infections, including 13 deaths.
Britain remains the worst-hit country in Europe. It has recorded 754 extra cases taking its total to 2,506, including one death.
In Australia, there are 237 extra cases at 2,436, with one death. In Japan, there are 160 more cases at 850.