A nurse in Samoa is facing criminal charges including one of negligence after two babies died last month.
The one year olds died straight after receiving the vaccination for measles, mumps and rubella.
Samoa's Police Commissioner, Fuiavailili Egon Keil said the nurse has also been charged with conspiracy to defeat the course of justice.
She was arrested on Saturday and will appear in court on Tuesday.
Her name and age has been withheld.
Samoa's Health Ministry working to win back trust in immunisations
Meanwhile, Samoa's Ministry of Health said efforts were underway to win back the public's trust after the deaths.
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Senior official with the ministry, Robert Thomsen said the MMR vaccination programme was still on hold but they've recommended restarting the immunisation programme for other childhood diseases.
"The benefits of immunisation, no one can deny that. But that's the challenge that we do have is to regain the confidence of the public in the immunisation programme, and that's why we are continuing to work with the WHO on addressing that."
Dr Thomsen said the government's keeping a close eye on Samoa's vaccine storage system.
He said it was adequate but could still be improved.
Dr Thomsen said after investigations into the babies' deaths are complete, there will be a catch up campaign for MMR to ensure children are protected.