Mexico says it will not participate in a Shanghai trade fair because of what it calls China's unacceptable policies regarding the H1N1 flu virus.
Mexico's trade promotion agency said Sunday that Mexican companies would not attend the food fair. Mexico and China have clashed since the outbreak of the illness, commonly referred to as swine flu, which has killed 48 people in Mexico.
Mexico has complained that China has unfairly quarantined Mexican travelers and canceled direct flights from Mexico.
Separately, China's official Xinhua news service said Monday that authorities have located and quarantined more than 130 of the 150 airline passengers who traveled with a man diagnosed as the first swine flu patient on the mainland.
Xinhua said the man's girlfriend, father and a cab driver were also quarantined. The man had flown to Beijing from the United States before taking another flight from Beijing to Chengdu.
On Sunday, the World Health Organization released updated figures for the swine flu virus showing the number of reported cases to be about 20 percent higher than figures released just one day earlier.
The WHO said, as of Sunday, 29 countries have officially reported a total of 4,379 cases of the illness. That is a jump of nearly 1,000 from Saturday's released figure of 3,440.
U.S. health officials said Sunday there have been 2,532 confirmed cases in 44 states. Three of those cases resulted in death. The most recently reported case was a man in the northwestern U.S. state of Washington. Officials said Saturday the man had underlying heart conditions and viral pneumonia at the time of his death.
Canada also has reported one swine flu death.
Some information for this report was provided by AFP, AP and Reuters.