Madam Comfort Asare, Ashanti Regional Deputy Director of Nursing Service, has advised voluntary health workers engaged for the routine immunisation programme to stick to instructions.
This, she said, is necessary to reduce the after effects of the drugs.
She was speaking at the regional launch of two new vaccines, pneumococcal and rotavirus, to fight pneumonia and diarrhoea infections among children under five years.
She said the introduction of the drugs demands careful planning and monitoring of the immunisation at every stage to determine their impact.
Launching the vaccines, Mr Kofi Opoku, Regional Administrator of Ghana Health Service, said the service is committed to reduce pneumonia, diarrhoea and other childhood diseases to bring down child mortality.
He said the service is doing everything possible to improve the survival of children and reduce deaths among them to at least 40 per cent by 2015.
Dr Asiedu Bekoe, Head of Surveillance, said the two vaccines could be given to a child at the same time without any effect.
The introduction of the new vaccines takes effect from May 2.