Naikhongchhari Upazila Nirbahi Officer Sadia Afrin Kochi has put herself in self-isolation after her husband treated a Covid-19 patient.
Upazila Health and Family Planning Officer Dr Abu Jafor Md Salim said she went to self-isolation Tuesday night.
He said, "Recently, a woman returned from abroad after performing Umrah. She was the first person in Cox's Bazar who tested positive for the virus. Kochi's husband Dr Md Yunus was in charge of her treatment."
Yunus was then sent to the isolation ward of Cox's Bazar Sadar Hospital.
Earlier, Bandarban district administration announced to lock down part of Lama, Alikadam and Naikhongchhari upazilas after the woman had tested positive for the virus.
The three upazilas have roads leading to Cox's Bazar district.
The local authorities in Bandarban said only pharmacies and commodity stores would remain open during the lockdown.