Influenza has already affected nearly 40,000 people in Thailand this year, and four of them have succumbed to the disease.
The Disease Control Department's director-general, Dr Jedsada Chokdamrongsook, however, firmly denied reports that the four deaths included a hospital staff member.
In dismissing the reports, he said that a hospital staff member who died had tested negative to influenza viruses A and B.
"Doctors have the opinion that cardiac arrhythmia (an irregular heartbeat) was the cause of his death," Jedsada said.
The Disease Control Department advised people to take good care of their health by having enough rest and taking regular exercise.
"Wash your hands often and avoid contacts with ill people," it said.
The department's advice emphasises that if people have a high fever and headache, they should see a doctor.