The number of swine flu fatalities in Argentina rose to five on Thursday with the death of an adolescent, while the total infections approached 1,000, the health ministry said.
Authorities said that out of 946 confirmed cases in the South American country, 65 have been hospitalized.
Argentina's first fatal case of the A(H1N1) virus, in a three-month-old baby, was reported Monday.
Swine flu has infected nearly 40,000 people around the world in 89 countries and territories, causing 167 deaths since late March, the latest WHO data showed Thursday.
Flu deaths in South America have been overshadowed by much larger numbers of fatalities to the north, in Mexico, the United States and Canada.
But the southern hemisphere is being closely watched by health experts concerned over how the virus will behave in winter, when conditions are ripe for the spread of flu.