
A woman now was admitted in a hospital and and given antiviral Oseltamivir drug for flu treatment for five consecutive day, Health Minister Witthaya Kaewparadai said.
The ministry has sent its Surveillance and Rapid Response Team (SRRT) to monitor four other persons who had close contact with the woman in a bid to prevent the spread of flu, he added.
Thailand now has tenth confirmed cases of the new virus, which has killed 125 people and infected 21,940 in 69 countries worldwide.
The woman whose identify was withheld, had visited the United States since March this year and returned to Thailand on June 5. She has been visited the US for three months for study and work.
She developed flu-like symptom such as headache, coughing, sore throat, running nose and was admitted at a hospital in Bangkok.
Her samples had been sent for testing on June 6 at the Department of Medical Science's laboratory. The results of the lab tests showed positive results.
"The patient is now recovered after being given antiviral drug for five days," said Permanent Secretary for Health, Dr Prat Boonyawongvirot.
The other four persons who had close contact with her were instructed to stay at home for three days. So far, they show no sign of the flu symptom.
The ministry previously has reported the country's first human to human transmission of influenza A (H1N1) within the country when a 19-year-old son whose infected mother returned from the US on May 25 spread the flu to him.