Bangladesh says it suspects measles has killed at least 98 children in the past three weeks, official data show, with the capital, Dhaka, ramping up vaccination efforts in the worst affected areas.

Last week, Prime Minister Tarique Rahman directed two senior ministers to travel across the South Asian nation of 170 million people to assess the scale of the crisis to help coordinate a response.

Data from the Ministry of Health and Family Welfare released on Sunday showed that the number of children aged six months to five years old with suspected measles symptoms soared to 6,476.

“Compared with past years, the number of affected children is higher, and the death toll is higher too,” Halimur Rashid, director at Communicable Disease Control, told the AFP news agency.