An unnamed Thai man suspected of contracting the deadly Middle East Respiratory Syndrome (Mers) was admitted to Rayong Hospital in Muang district in Rayong province Tuesday.
Sopon Mekthon, director-general of the Department of Disease Control (DDC) said the man contracted type A influenza and that his condition had improved during isolation in hospital overnight.
He remains under quarantine so doctors and technicians can perform more tests on his phlegm to double-check the initial tests.
A friend of the man has also been admitted for monitoring. The second man had no symptoms of illness but will remain under quarantine for several days.
The first patient was identified only as a 27-year-old male employee of a petrochemical plant in the province.
He went to the hospital with Mers-like symptoms on Tuesday. A background check indicated that he was recently in contact with three friends who had just returned from South Korea, and one of them died shortly after returning to his home village in Ubon Ratchathani province. The cause of his death was unknown on Wednesday.
His body was place in isolation for post-mortem checks.
Mr Sopon urged the public not to panic as the Public Health Ministry had an effective disease monitoring system in place.
The public can call a 24-hour hotline on 1422 for inquiries.
An unidentified Thai man suspected of contracting the deadly Middle East Respiratory Syndrome (Mers) was admitted to Rayong Hospital in Muang district in Rayong province Tuesday. Overnight tests proved negative on Wednesday, the Public Health Ministry said.
The patient was identified only as a 27-year-old male employee of a petrochemical plant in the province.
Prasit Thongsadayu, a doctor at Rayong Hospital, said doctors have yet to confirm if the man has Mers because they are still waiting for the test results.
The man was quarantined in a makeshift tent on the hospital's grounds before he was transferred to a room for patients infected with respiratory tract diseases.
A source from the hospital said the patient was rushed to the hospital in an ambulance Tuesday evening after he developed symptoms similar to Mers two days ago.
According to a background check, he fell ill after three of his friends, who had worked on a livestock farm in Korea, visited him. During the visit, he noticed one of his friends also had similar symptoms to him.
His friend died shortly after he went back to his hometown in Ubon Ratchathani province, and the cause of his death has yet to be verified.
Dr Prasit said people with Mers will show symptoms similar to the flu, including high fever, dry cough, severe shortness of breath and diarrhoea. The disease can be transmitted through sneezing and coughing and those who contract it can die within three to four weeks.
Thailand's only confirmed Mers patient was a 75-year-old man from Oman who was visiting Thailand with his family in June.
He returned home earlier this month after being quarantined for treatment at the Bamrasnaradura Infectious Diseases Institute.