The pentavalent vaccines, which protect against five diseases with a single shot, spoiled because they were not stored at the proper temperature, officials said.
“An inquiry commission was formed to investigate the case and has suspended two officials for negligence,” Dr Saqlain Ahmad Gilani, the national manager at the Expanded Programme on Immunisation told AFP.
“The vaccines were stored on a higher temperature than required.”
The vaccines worth $3.7 million were donated by the United Nations Children’s Fund (UNICEF), he said.
State minister of National Health Services Regulation and Coordination Saira Afzal Tarar confirmed the incident and said it would lead to an improvement in vaccine monitoring.
Tarar said the vaccines were ruined because of “departmental conflicts”.
“It appears that one person was switching off the generator when it was turned on apparently to save fuel,” she said.
She said the inquiry report will be finalised in a week and made public and insisted more than half of the vaccines could still be used.
Immunisation of children remains a big challenge for Pakistan, with polio a particular problem. The pentavalent vaccine does not cover polio.
Polio vaccination teams have repeatedly come under attack in the country.
On Monday, police arrested more than 450 parents in Peshawar for refusing to vaccinate their children against polio.
At least nine new cases have so far been detected in 2015. Last year, the number of polio cases recorded in Pakistan soared to 306 which is the highest in 14 years. (AFP)