At 1:30 am on May 11, 2009, influenza A(H1N1) was eliminated in two probable cases that occurred in Taipei after running sequence alignment.

The two aforementioned cases returned to Taiwan from Portland, the United States, via Tokyo on May 5, 2009.Upon their return, they developed influenza-like symptoms.After hospitalization, they were reported as “persons under investigation”.Their laboratory test results were positive for influenza A and negative for H1 and H3, meeting the World Health Organization’s case definition for a probable case of influenza A(H1N1).Since the cases recently returned from the US where 90% of the probable cases have been confirmed cases, the Central Epidemic Command Center (CECC) immediately took necessary actions.After further confirmation by RT-PCR and sequence alignment, influenza A(H1N1) was eliminated in those two probable cases.

CECC has instructed to stop the implementation of relevant control measures for those two cases.However, the influenzaＡ(H1N1) outbreaks around the world are still ongoing.CECC remains on high alert over the threat posed by influenza A(H1N1).