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BEIRUT, July 30 (Reuters) - A Lebanese man suffering from a serious illness died from the H1N1 swine flu strain on Thursday, Health Minister Mohammad Khalifeh told Reuters.

The 30-year-old victim had been receiving treatment for leukemia when he contracted the virus, possibly from relatives who had just travelled from Australia to Lebanon, the minister said.

Lebanon has recorded more than 100 cases of H1N1.

H1N1 swine flu has swept around the world in weeks, infecting millions and killing more than 800 by official counts. While only a "moderate" pandemic by World Health Organisation standards, it could worsen as temperatures cool in the northern hemisphere, making conditions better for viruses. (Reporting by Laila Bassam; Editing by Jon Hemming)