Brazil has registered 899 deaths from swine flu, maintaining its status as the country worst-hit by the pandemic, according to the health ministry in South America's largest nation.
In announcing the data, the ministry also said that the number of serious cases in the country "fell for the fifth straight week," indicating a reduction of the spread of the A(H1N1) virus.
Brazil became the country with the highest death toll in late August when it surpassed the United States, which now has 593 swine-flu-related fatalities. Brazil's neighbor Argentina has 512 deaths.
Southeastern Sao Paulo state has been the worst hit, with 327 deaths, followed by Parana in the south with 222. Rio de Janeiro has recorded 84 deaths.
On Tuesday, the WHO warned swine flu will have a "devastating effect" on poor countries where lives will be lost due to ill-equipped health care facilities.
"The pandemic will test the world on the issue of fairness in a substantial way," WHO chief Margaret Chan said in a speech in Copenhagen.
She noted that swine flu will cause "manageable disruption" in affluent countries.
But it will "almost certainly have a devastating impact in countries with few health facilities and staff, no regular supplies of essential medicines, little diagnostic and laboratory capacities, and vast populations with no access to safe water and sanitation," she said.
US drug regulators Tuesday approved a swine flu vaccine, keeping officials on track to begin a mass vaccination campaign by next month.
The US government has purchased 195 million doses of swine flu vaccine and will make shots against the influenza A(H1N1) virus available free of charge starting next month, Health Secretary Kathleen Sebelius said.
"The large-scale 2009 H1N1 vaccine program will begin mid-October with small amounts of vaccine becoming available the first week of October," she said.