In Mexico, where the first cases of A-H1N1 swine influenza were detected last month, government officials say the disease appears to be waning and that people can start returning to their normal lives this week. But medical experts caution that the flu still poses a threat.

Police officers, wearing mask as a precaution against the swine flu, patrol a street in Mexico City, Sunday, 03 May 2009

On Wednesday, many of the businesses in Mexico that closed because of the flu epidemic last week are scheduled to reopen. On Thursday, universities and high schools will reopen, followed by elementary schools on Monday. Mexican President Felipe Calderon says the situation has stabilized.

He says the country can begin on a path toward normalcy, although he cautioned the virus is still present in the population and that people should continue to take precautionary measures to prevent its spread.

Mexico's finance minister says the swine flu outbreak has cost his country's economy at least $2.2 billion. Business leaders estimate that Mexico City alone has lost up to $60 million a day during the past week, after local authorities shut down bars, restaurants and other venues where people normally gather. Similar actions were taken in other parts of the country, as officials, on the advice of health experts, sought to limit the spread of the disease.

While many Mexicans have worn face masks for protection, there have also been many expressing skepticism over the flu crisis. In a nation where millions of people live on the edge of poverty, they say being out of work for several days poses risks that might rival that of the flu.

People, wearing face masks as a precaution against swine flu, walk after crossing from U.S. to Mexico at the San Ysidro crossing port in Tijuana, Mexico, 30 Apr 2009

Mexicans have also bristled at measures taken by other nations to protect themselves from the swine flu, which began in Mexico. U.S. travelers have canceled trips to Mexico in such large numbers that Houston-based Continental Airlines, which operates the largest share of U.S. flights to Mexico, cut back its operations and began using smaller planes for Mexico trips. A few countries, including China, Cuba and Argentina, canceled all flights to and from Mexico.

China quarantined a group of Mexican citizens out of fear that they were infected with the virus. Mexican media reports have criticized such actions as an affront to the nation. President Calderon says Mexico's actions in tracking the swine flu and preventing its spread may have saved the rest of the world from a large, deadly epidemic.

But health officials from various international organizations working in Mexico say it is too early to say what this strain of flu might do in the months ahead. They note that it might wane in the northern hemisphere as the flu season subsides, but increase in the southern hemisphere, where the flu season is just beginning. They also warn of a much more severe outbreak in the months ahead if the virus mutates or combines with normal seasonal flu strains into a more dangerous form.

Scientists are working on a vaccine against the H1N1 virus. But they say it could take months to develop it and produce sufficient quantities to protect people around the world from a major outbreak.