Mexico said its H1N1 flu outbreak appeared to be "in a stabilization phase" on Saturday, as it tried to mitigate the economic cost of the crisis, joining Canada and the United States in hitting out at pork boycotts.
Mexico said the national death toll from the epidemic reached 19, as health officials around the world remained on high alert as more cases were confirmed in Asia, Europe and the Americas.
"I believe we have enough elements to say that we are in a stabilization phase," said Mexican Health Minister Jose Angel Cordova, who confirmed that the tally of cases, including those who have died, had risen to 473.
The World Health Organization (WHO) reported at least 615 cases in around 15 countries.
In Geneva, a WHO official indicated the virus had not spread in a sustained way outside of the Americas, a condition necessary to declare a full global pandemic.
"We see no evidence of sustained community spread outside North America," said Mike Ryan, WHO Director of Global Alert and Response.
In the United States, the Centers for Disease Control and Prevention (CDC) reported 160 confirmed cases spread across 21 states and said additional cases and perhaps even deaths could follow.
Authorities in New York said the city may have seen more than 1,000 cases, but carriers were likely recovering or recovered.
In Canada, some 30 new cases were reported on Saturday, bringing the total number of people infected throughout the country to over 85.
Officials also confirmed H1N1 cases had been detected in a pig herd in Alberta, likely contracted from a man who recently returned from Mexico.
The three North American nations tried to mitigate the economic impact of the crisis, hitting out at countries which had slapped bans on their pork products.
"We strongly urge the international community not to use the outbreak of the H1N1 influenza as a reason to create unnecessary trade restrictions and that decisions be made based on sound scientific evidence," the country's said in a joint statement.
Nearly 20 countries, including China and Russia, have imposed bans on the importation of pigs and pork products from Canada, the United States and Mexico.
Mexico also hit out at China, which it said had placed "unjustified" health measures being taken against Mexicans arriving to the country.
Elsewhere South Korea, Ireland and Italy confirmed their first cases, but all three countries said their patients had made swift recoveries.
Hong Kong confirmed a 25-year-old Mexican who arrived from Mexico via Shanghai had brought the first case of swine flu into a city living in fear of a repeat of the SARS virus and bird flu outbreaks of recent years.
Police on Friday sealed off the Hong Kong hotel where he had briefly stayed and placed the building and more than 300 guests and staff under a seven-day quarantine.
The case sparked a regional alert, with China immediately ordering health authorities to track down and isolate the man's fellow passengers, while some pharmacies in Hong Kong sold out of face masks.
India and Japan also reported suspected cases, with Japanese authorities saying a four-month-old baby from the United States was being tested.
The alarm caused by the flu was evident in Egypt, which began slaughtering its 250,000 pigs began despite the WHO insisting there was no evidence that the animals were transmitting the virus to humans.
Benin became the second African country to report a suspected case of the flu as Health Minister Issifou Takpara told AFP that a European woman may have contracted the virus during a trip in Mexico.
British officials confirmed two new cases, bringing the total to 15, including one person who appeared to have been infected in Britain by someone recently returned from Mexico.
Israel reported a third case -- a man recently returned from Mexico -- while confirmed cases in Spain rose from 13 to 15. German officials said a patient had infected a fellow patient and a nurse, bringing the number of cases there to six.
But health authorities said the world appeared better prepared to fight an epidemic than a few years ago, and promised that a vaccine was only months away.
"We have no doubt that making a successful vaccine is possible in a relatively short period of time," Marie-Paule Kieny, director of WHO's Initiative for Vaccine Research said on Friday. Vaccine production, she added, could take four to six months.
Most cases outside Mexico have involved only mild symptoms of the illness treatable with existing flu medicines.
Some experts have suggested the virus may have weakened as it was carried outside the country.