A child died from an "unknown disease" and around 40 people were affected in a span of three days in a small neighbourhood of Bandarban, said locals.

People have started falling ill in Puraton Lailiya Mro Para, a remote area in Lama upazila, since Friday, they said, adding that one-year-old Jai Hla Mro died on that day.

His father Menhath Mro said his another son, aged three, is also in critical condition due to the same disease.

Almost half of total 82 people in the neighbourhood have been affected by the disease. All of them are illiterate, said Long Tong, one of the residents.

The nearby upazila health complex is 25km from the area and there is no transport facility, which make them reluctant to go to doctors to receive treatment, he said. 

Affected persons' symptoms are high fever, cough and rash all over the body, said Long Tung Mro Karbari, community leader of the area, adding that most victims are children aged between three months and 15 years.

"I cannot move as I feel pain in my whole body," said Kom Ching Mro, a patient.

Another resident, Youngri Mro, said, "We all are in panic as the situation is getting worse."

The community leader alleged that doctors or community health service providers never visit the area, which is out of vaccination coverage.

However, upazila health officer Dr Mahmudul Haque said they do so but not regularly, as the area is hard to reach.

Civil Surgeon Dr Aung Swi Prue Marma said, "We already sent a medical team to the affected area. Once they return, we will be able to tell the reason."

Lama Upazila Nirbahi Officer Nur-a-Jannat-Rumi told The Daily Star the team is monitoring the situation.

Mintu Kumar Sen, chairman of local union parishad, said they have taken initiatives to raise awareness among the community about vaccination.