Mexican health officials reported the swine flu death toll had risen to 42 on Wednesday, just as businesses and services reopened after a five-day shutdown aimed at curbing the spread of the virus.

Health officials are still working through backlogged cases and have confirmed that 42 people died from complications related to the H1N1 virus — including three deaths in the past two days.

An additional 1,070 patients have also been confirmed as suffering from the flu, said Health Secretary Jose Cordova.

Businesses and public services reopened on Wednesday as a five-day government-ordered shutdown concluded in the country. Most people on the streets of Mexico City, which is considered the epicentre of the virus outbreak, put aside their medical masks as they attempted to return to a normal schedule.

"We have a lot of confidence nothing is going to happen," said security guard Irineo Moreno Gonzales. "Mexicans have the same spirit we've always had. We're ready to move forward."

Universities and high schools were scheduled to reopen on Thursday. Elementary schools won't reopen until May 11.

Mexico's top priority will be persuading tourists to come back to the country, said Finance Secretary Agustin Carstens.

The outbreak cost Mexico's economy at least $2.2 billion, Carstens said. The country has announced a $1.3 billion stimulus package, mostly for tourism and small businesses, the sectors hardest hit by the epidemic.

Mexico will temporarily reduce taxes for airlines and cruise ships and cut health insurance payments for small businesses.

Caution urged

But some officials cautioned against a rush back to normalcy in Mexico.

"The scientists are saying that we really need to evaluate more," said Dr. Ethel Palacios, deputy director of the swine flu monitoring effort in Mexico City. "In terms of how the virus is going to behave, we are keeping every possibility in mind…. We can't make a prediction of what's going to happen."

The WHO reported that 1,893 cases of the virus have been confirmed in 23 countries as of Wednesday morning.

The United States has reported 642 confirmed human cases, including two deaths. In Canada, 201 cases of swine flu have been confirmed by health officials.

The number of confirmed cases and deaths reported by WHO may not match the numbers reported by countries, because those countries may not yet have reported them to the international health body.

Experts have said the known cases were almost certainly only a fraction of the real total.

The Southern Hemisphere may be particularly at risk as the region enters winter and its flu season, according to some medical experts.

Seasonal flu viruses could combine with swine flu, creating a new strain that is more contagious or dangerous.

Anti-flu drugs shipped

The UN health body is shipping 2.4 million treatments of anti-flu drugs to 72 countries "most in need," and France has sent 100,000 doses worth $1.7 million to Mexico.

In a press release on Wednesday, the WHO urged people who are ill to delay international travel and advised anyone showing symptoms of the virus to seek medical attention.

"Individuals are advised to wash hands thoroughly with soap and water on a regular basis and should seek medical attention if they develop any symptoms of influenza-like illness," the statement said.

But the WHO, which currently is at a Phase 5 global pandemic alert, has not yet advised any restrictions on regular travel or closure of borders and has continued to stress that there is no risk of infection from the consumption of pork.

UN Secretary General Ban Ki-moon said he will ask the governments that have implemented trade and travel restrictions to reverse the policy because they lack a clear scientific basis.

China, Argentina and Cuba are among the nations banning regular flights to and from Mexico.

China has also banned the import of pork from Mexico, some U.S. states and Alberta, despite the WHO assuring that the virus is not spread through the consumption of pork.

Several North American travellers have also been put under preventive quarantine in China.

Dr. David Nabarro, senior UN co-ordinator for influenza, said countries must explain to WHO their rationale for such measures, and said that their effectiveness is minimal at best.

"We want to be very clear that the World Health Organization is not recommending travel restrictions related to the outbreak of this novel influenza," Nabarro said.

Quarantines lifted

More than 100 Mexican nationals who were being quarantined at hospitals and hotels in China were returned home on a chartered government plane Wednesday.

China also lifted a swine flu preventive quarantine on a group of Canadian students, being kept in a Changchun hotel, two days early. Canadian officials applied diplomatic pressure when none of the students under quarantine displayed any symptoms of the virus.

Meanwhile, an aircraft carrying about 100 Chinese nationals stranded in Mexico because of the outbreak was able to return to Shanghai on Wednesday. The passengers are reportedly healthy but have been place in preventive quarantine for one week.

China has defended its measures to block the swine flu virus, saying an outbreak in the densely populated nation could be catastrophic.

With files from The Associated Press