Nearly 10,000 cases of swine flu have been confirmed in 40 different countries around the world, the World Health Organization (WHO) has said.
The WHO said 79 people are known to have died from the new virus.
The news comes as the WHO and UN hold talks with top pharmaceutical firms to discuss the production of a vaccine.
Correspondents say there is concern about the global distribution of a possible vaccine after wealthy states pre-ordered large stocks.
The WHO says the global tally of swine flu cases stands at 9,830, after rising by 1,001 in one day.
Most of the new flu victims were in Mexico, which reported some 545 cases, and the US, where 409 new cases were confirmed. There were also 34 new cases in Japan.
Five confirmed cases were reported in Panama, three in Chile, two in El Salvador and one each in the UK, Peru and China.
Five new deaths have also been reported - four in Mexico and one in the US.
Scramble for Vaccines
UN chief Ban Ki-moon and WHO head Margaret Chan are holding talks in Geneva with pharmaceutical companies to ask for commitments over the production of a vaccine.
Mr Ban will be looking for a commitment to increase capacity and to produce vaccines at a fair price, the BBC's Imogen Foulkes reports.
Pharmaceutical companies are committed to producing a seasonal flu vaccine and somehow capacity has to be found to produce an affordable swine flu vaccine as well, she says.
Rich countries such as Britain and the US have pre-ordered vast stocks of such a vaccine before a single dose has been produced, leading to concerns about future global supplies.
Michele Childs of the medical charity Medecins Sans Frontieres (MSF) said that wealthy countries were "putting in place these agreements with vaccine manufacturers to basically jump the queue".
"What needs to be done is all of the countries need to agree how it will be equably shared, based on need, so if one country has got a huge outbreak then they need to be getting the vaccines first," she said.
"But that debate is not happening."
In Japan the number of swine flu cases has continued to rise rapidly.
The new cases brought the total number of people to have caught the virus in Japan to at least 176, according to authorities there.
Just four cases had been confirmed in Japan as of Friday - people who had returned from Canada.
The first case in someone who had not been abroad - a 17-year-old student in Kobe - was reported on Saturday.
Japanese media say the new wave of infections makes Japan the fourth-most infected country in the world, after Mexico, the US and Canada.
Officials doubled the closures of schools and universities in Hyogo and Osaka on Tuesday, bringing the total to more than 4,000.
None of the patients in the new wave of Japanese infections were reported to be in serious condition.