A Thai man who just returned from the United States has been infected by the Influenza A/H1N1, the fourth case in Thailand, Public Health Minister Witthaya Kaewparadai on Sunday said.

The 48-year-old patient, whose name was undisclosed, returned from the United States on the night of May 25, and was admitted to a Bangkok hospital with slight fever and sore throat the following day, Mr. Witthaya said. Health officials closely watched the patient and gave doses of Oseltamivir to five of his family members for five consecutive days.

The patient's saliva samples were examined by the Department of Medical Sciences' National Influenza Center and Siriraj Hospital and both confirmed that the samples contained the A/H1N1 strain, the website of the Bangkok Post reported. However, the patient had fully recovered and were allowed to return home.

Thailand had its first two cases of the influenza earlier May and confirmed a third case on Saturday.

(Xinhua News Agency May 31, 2009)