Thailand has 23 species of horseshoe bats, but there has been no investigation before.
The source of the virus remains a matter of debate after its appearance in China at the end of last year.
The World Health Organization (WHO) said in April that all available evidence suggests it originated from bats in China, but it was not clear how the virus had jumped the species barrier for humans.
The research team in Thailand includes Supaporn Wacharapluesadee, who identified the country’s first case of VOCIDE-19 in January.
“Right why we need to investigate the horseshoe bat is because there are reports from China that the COVID-19 virus is similar to the virus found in the horseshoe bat,” Supaporn said.
Thailand was the first country outside China to record a case of the virus. To date, it has reported 3,134 cases and 58 deaths.
Researchers from the Department of National Parks, Chulalongkorn Hospital and Kasetsart University entered the cave on Thursday night and reappeared in the early hours of Friday with samples of bat blood, saliva and feces.
Investigators were concerned that villagers in the area were at risk of infection.
Residents were known to eat bats, Supaporn said, adding that adequate education and information programs were needed.
Local transmissions have decreased in recent weeks with new cases from Thais returning from overseas. (Reporting by Jiraporn Kuhakan and Chayut Setboonsarng Editing by Clelia Oziel)