The new strain of influenza A/H1N1continued to spread around the world on Monday as more than 4,500 people in 29 countries have been confirmed to have been infected with the disease.

The Chinese mainland reported its first confirmed case in southwest Sichuan Province, the Ministry of Health said on Monday.

A 30-year-old Chinese man, flying back to China from St. Louis of the United States via Tokyo, was found with fever and was tested positive for the A/H1N1 influenza, said the ministry.

The man is being treated at the Chengdu Infectious Disease Hospital, and people having close contact with him are also isolated for medical observation.

In China's Taiwan, tests on two people earlier thought to have been the first cases there showed that they do not have the virus, local health authorities said on Monday.

Japan on Sunday reported its fourth case, a male student who arrived at Narita airport from the United States on Friday.

The student, 16, was on board the same flight as a teacher and two other students who were confirmed Saturday to be Japan's first cases of the epidemic.

All of the four were among a group that returned from a school trip to Canada via Detroit.

Colombia has confirmed two more cases of the epidemic after receiving positive tests results, the government said on Sunday, noting the country has found a total of three confirmed cases and 189 suspected cases so far.

The Panamanian Health Ministry announced Sunday 12 new confirmed cases, bringing the country's total confirmed cases to 15. The number made Panama the country with the most confirmed cases in Central America.

Among all the 15 patients, nine are adults, and the remaining six are children aged from eight to 14. All of them did not have death danger, said the ministry.

Canada reported five new cases on Sunday, three in western Alberta province and two in Saskatchewan, bringing the total number of people infected with the virus to 286.

So far, only Canada's northern territories and the island Newfoundland province in the North Atlantic Ocean have not reported any cases.

In the United States, which has overtaken Mexico as the world's most affected nation, the disease has spread to 44 states with a total of at least 2,532 cases, the Centers for Disease Control and Prevention (CDC) reported Sunday.

The country reported its third death case, a man in his 30s in Washington state, on Saturday.

Though many of the cases in the country have been mild, the CDC warned that more cases, more hospitalizations and more deaths from this outbreak will occur over the coming days and weeks.

The CDC said it has developed a kit for testing whether individuals are carrying the disease.

France confirmed one more new case Sunday, bringing the country's total number of confirmed cases to 13.

However, the government said none of the patients in France involved a severe form of the illness that can kill.

In Britain, health officials confirmed seven new cases in eastern England Sunday, adding the total cases to 55.

Sweden confirmed Sunday its second case of the influenza, saying the patient is a young man who recently returned from New York.