Initial research has already pointed to bats as the source of the virus that has infected more than 20.5 million people and caused the deaths of over 748,000 worldwide, according to Johns Hopkins University data.
The closest match to coronavirus has been found in horseshoe bats in Yunnan in southern China.
Thailand has 19 species of horseshoe bats but researchers said they have not yet been tested for the new coronavirus.
Thai researchers hiked up a hill in Sai Yok National Park in the western province of Kanchanaburi to set up nets to trap some 200 bats from three different caves.
The team from the Thai Red Cross Emerging Infectious Diseases-Health Science Centre took saliva, blood and stool samples from the bats before releasing them.
They worked through the night and into the next day, taking samples not only from horseshoe bats but also from other bat species they caught in order to better understand pathogens carried by the animals.
The team was headed by Supaporn Wacharapluesadee, the centre’s deputy chief, who has studied bats and diseases associated with them for more than 20 years.
She was part of the group that helped Thailand confirm the first Covid-19 case outside China in January and believes it is likely the team will find the same virus inside these bats.
“The pandemic is borderless,” she said. “The disease can travel with bats. It could go anywhere.”